BMJ Openhave explored the postterm effect on maternal mental health.[26-30] Blom et al....
Transcript of BMJ Openhave explored the postterm effect on maternal mental health.[26-30] Blom et al....
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A PROSPECTIVE STUDY OF 33 PRETERM MOTHER-INFANT
(<33 GA) INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH REACTIONS,
PREGNANCY AND BIRTH COMPLICATIONS
Journal: BMJ Open
Manuscript ID: bmjopen-2015-009699
Article Type: Research
Date Submitted by the Author: 12-Aug-2015
Complete List of Authors: Misund, Aud R; University College of Oslo and Akershus, Health science Bråten, Stein; University of Oslo, Dept. of Sociology and Human Geography Nerdrum, Per; University College of Oslo and Akershus, Health science Pripp, Are; Oslo University Hospital, Department of Biostatistics, Epidemiology & Health Economy Diseth, Trond; Oslo University Hospital and University of Oslo, Department of Clinical Neurosciences for Children, Women and Children’s Division and Department of Medicine
<b>Primary Subject Heading</b>:
General practice / Family practice
Secondary Subject Heading: Mental health, Obstetrics and gynaecology, Reproductive medicine, Paediatrics
Keywords: Neonatal intensive & critical care < INTENSIVE & CRITICAL CARE, MENTAL HEALTH, Maternal medicine < OBSTETRICS, PERINATOLOGY, TRAUMA MANAGEMENT, Child & adolescent psychiatry < PSYCHIATRY
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A PROSPECTIVE STUDY OF 33 PRETERM MOTHER-INFANT (<33
GA) INTERACTIONS AT SIX AND 18 MONTHS AND THE IMPACT
OF MATERNAL MENTAL HEALTH REACTIONS, PREGNANCY AND
BIRTH COMPLICATIONS
Aud R. Misund1 Stein Bråten
Per Nerdrum
Are Hugo Pripp
Trond H. Diseth
ABSTRACT
Objective:
Pregnancy, birth and health complications, maternal mental health reactions following
preterm birth and their possible impact on early mother-infant interaction at six and 18
months postterm age (PA) were explored. Predictors of mother-infant interaction at 18 months
PA were identified.
Design and methods:
This prospective longitudinal and observational study included 33 preterm mother-infant (<33
GA) interactions at six and 18 months PA from a socio-economic low risk middle class
sample. The parent-child early relational assessment scale (PCERA) was used to assess the
mother-infant interaction.
Results:
Mothers with clinical important case scores in the Impact of Event Scale, the General Health
Questionnaire, and PTSR/PTSD diagnosis at two weeks postpartum (PP) showed significant
better outcome scores than the mothers without clinical case scores in five PCERA subscales
at six months and in two PCERA subscales at 18 months PA.
1 Faculty of Health Sciences, University College of Oslo and Akershus and Department of Medicine, Institute of
Clinical Medicine, University of Oslo, adr: PO Box. 4 St. Olavs plass, N-0130 Oslo, Norway e-mail:
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“Bleeding in pregnancy” predicted lower quality in preterm mother-infant interaction in six
PCERA scales, while high “Maternal trait anxiety” predicted higher interactional quality in
two PCERA scales at 18 months PA.
Conclusions:
Our study detected a correspondence between early pregnancy complications and lower
quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Strengths and limitations of this study:
The longitudinal design, the high response rate and the use of well validated psychometric
instruments (IES, GHQ and STAI) and interactional assessment tool (PCERA) are strengths
in this study.
Ethical considerations called for a referral procedure to meet need for psychological treatment
among the attending preterm women and it is a limitation that we could not assess the extent
to which our results were influenced by the psychological treatment.
The present study describes a small preterm group and one should be cautious about
generalising from this study.
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INTRODUCTION
Early parent-infant relationships that are well functioning seem to be critical to
preterm children. Preterm children face severe risk of cognitive, learning, and behavioural
disorders from early cerebral injuries,[1-6] and show more psychiatric symptoms in
adolescence.[7] Early parent-infant relationships that are well functioning seem to prevent and
restore some of these difficulties in preterm children.[8, 9]
Good quality in mother-child interactions have been reported to facilitate the infant’s
emotional, behavioural, cognitive, and neurobehavioral development.[10-15] The
interactional quality is also found to be related to the child’s physical health.[16, 17]
The maternal stress reaction following preterm birth has been highlighted as a risk
factor in preterm dyads in several studies.[18-23] Postpartum depression has been identified
as predictor for interactional difficulties in term dyads[24] and reported as a risk factor for
difficulties in preterm mother-infant dyads.[25] Only a limited number of studies, however,
have explored the nature of mothers’ mental health reactions following preterm birth with
psychometric tools, and their impact on mother-infant interaction. Several studies, however,
have explored the postterm effect on maternal mental health.[26-30] Blom et al. interestingly
reported that certain perinatal complications such as preeclampsia, hospitalization, emergency
caesarean, and fetal distress predicted higher depression outcomes in a normal population
sample. An unaddressed trauma reaction is known to predispose for posttraumatic stress
disorder (PTSD) with long term effects on mothers’ mental health. The effect of mothers
postpartum PTSD on mother-infant interaction and infant’s development is less explored.[31]
In addition only a limited number of studies have explored the maternal posttraumatic stress
responses following preterm birth,[32-39] and their impact on mother-infant interactions.[36,
40, 41]
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The results from preterm mother-infant interaction research are contradictory.
Different measurements and definitions being used, as well as the complexity of mother-
infant interactional studies may have contributed to these differences. Some studies have
reported that preterm mothers showed more stimulating behaviour and were emotionally
withdrawn, as well as non-synchronous in their interaction with the child,[40, 42-48] and
others have found no interactional differences between preterm and full term dyads.[40, 49-
54] Korja et al. detected that caregivers’ physical closeness with the infant was more
important to interactional quality than infants’ prematurity.[52] Finally, it is interesting that
several studies have shown that mothers are intensifying their efforts to be available and
supportive to their premature babies’ needs.[55-60] The need for further exploration of the
complexity of factors influencing the early mother-infant relationship long-term in preterm
dyads seems essential.[6, 61]
The focus of this longitudinal study is broad and explorative. We have examined the
possible influence of physical complications and maternal mental health reactions following
preterm birth, assessed at four time points, and their impact on early mother-infant interaction
at six months PA and 18 months PA. To our knowledge, these associations have not been
explored in other studies. Psychometric tools and tentative psychiatric diagnosis (anxiety,
depression, and PTSR/PTSD) were used to assess maternal mental health reactions following
preterm birth.
It should be noted that this paper is an extension of our previous studies of short- and
long-term maternal mental health reactions following preterm birth.[38, 39]
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METHOD
Participants
From June 2005 to July 2008 over two periods of 8 and 10 months, the psychological
responses of 29 consecutive mothers of 35 premature children born before 33rd week of
pregnancy were assessed at a high-specialized neonatal intensive care unit (NICU) at Oslo
University Hospital, Norway. The data collection was performed as soon as the mothers were
able to attend an interview following preterm childbirth: within two weeks postpartum (T0)
median 11 days (4-30); then within two weeks after hospitalization (T1), median time
postpartum 2.7 months (0.2-4.7); then at the infant’s six months postterm age (T2), median
time postpartum 8.5 months (7.6-10.4); and at the infant’s 18 months postterm age (T3),
median time following birth 20.6 months (19.2-23.4). Data collection of mother-infant
interaction was collected only at T2 and T3. Mothers of severely ill babies with uncertain
survival and non-native speakers were not included (Figure 1).
FIGURE 1 ABOUT HERE
Semi-structured interviews and standardized mental health screening questionnaires
were used to collect data about socio-demographics, the pregnancy and birth, child’s health
status, and mothers’ mental health reactions. Medical charts were used to double-check the
data of child’s health status, and pregnancy and birth. The studied sample was homogeneous
regarding high scores on socio-demographic variables such as education, income, and housing
standard. Most mothers were giving first time birth late in their twenties or early thirties. All
lived with the child’s father and none reported any relationship problems (Table 1).
The participating mothers’ mental health reactions following preterm birth have
been assessed at T0, T1, T2, T3 and methods and results are described in detail in our earlier
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papers.[38, 39] Maternal mental health problems were assessed at every time points (T0, T1,
T2, T3) by standardized psychometric methods with well-established reliability and validity:
Impact of Event Scale (IES), one of the key psychometric assessment methods in traumatic
stress research,[62, 63] the General Health Questionnaire (GHQ) 30-item version, a widely
used screening instrument for assessing the presence of distress, psychopathology and overall
well-being,[64, 65] and the State/Trait Anxiety Inventory (STAI-X1/X2)[66] is widely used to
assess maternal anxiety. Scores above the threshold for identifying a psychiatric case is
referred to as a clinical important case score.
Based on all information available in a clinical perusal of the psychometric self-reports
IES, GHQ and STAI of each of the 29 preterm mothers, and blinded to the physical and socio-
demographic characteristics of the mothers and their children, a tentative clinical diagnosis
was made where appropriate based on the clinical descriptions and diagnostic guidelines in
the ICD-10 Classification of mental and behavioural disorders, and was assessed by a
psychiatrist (last author).
A prevalence of maternal posttraumatic stress responses/disorders (PTSR/PTSD) two
weeks postpartum (T0) of 52% and maternal PTSD at 18 months postterm age (T3) of 23%
was revealed. On the other hand, depression was detected among 24 % of the mothers two
weeks postpartum and among 8% of the mothers at T3. Anxiety decreased from 7% at two
weeks postpartum to zero at T3.
Fourteen of the mothers received psychological support at the hospital during their
infants’ NICU stay. Eleven of these mothers were referred for further psychological treatment
after discharge from the hospital. Altogether, 20 mothers that met the criteria of clinical
diagnoses were referred for adequate psychological treatments such as psychotherapy,
psychopharmacology treatment, and mother-infant interactional treatment. Five of the
mothers refused the referral for psychological treatment, and only one of them filled the
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criteria for a tentative clinical diagnosis (PTSD/Depression) at T3. The prevalence of
pregnancy and birth complications and maternal mental health reactions following preterm
birth are reported in earlier papers.[38, 39]
Data collected at 2 weeks postpartum (T0) about sociodemographics, physical
complications and maternal mental health reactions following preterm birth are presented in
Table 1.
TABLE 1 ABOUT HERE
Measures
Mother–infant interaction in a free-play situation was video recorded at six and 18
months PA. According to Clark (1985) by six months of age, dyadic mutuality and dyadic
regulatory processes are perceptible while at 18 months, the infant's own communication
skills are easier to identify in interaction [67]. The interaction situation was recorded in a
consultation room at the psychiatric clinic for children and families situated in the same
building as the hospital the children were born in, except for four video recordings at 18
months PA that were recorded in their homes. The recordings were performed when child was
awaken and interested in a play session with mother. Recordings were stopped and performed
later when child became too distressed or sleepy to play. A therapist (first author) instructed
the mothers about the procedure. For the video recording, the mother and the infant were
placed on a soft mat with age-appropriate toys. Instructions by the investigators given to the
mother prior to the video recording were: ‘This is a free-play time with your child. You can
use the toys, or you can play without the toys. Try to play or be with your infant as you
usually would be”. Video recordings were obtained from all mother-infant pairs.
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The recordings were five minutes long. The mother-infant interaction in the free-play
situation was analysed using the Parent-Child Early Relational Assessment (PCERA)
method.[67] The PCERA is developed to assess affective and behavioural aspects that both
the parent and infant bring into the interaction,[67] and the validity of the free play situation
has been established.[68, 69] Video recordings allows thoroughly analysis of the interactions
several times and in short and slow sections that can identify areas of strength and of concern
in the mother-infant interplay. The PCERA consists of 29 parental items, 28 infant items and
eight dyadic items. The assessment rates the frequency, duration and intensity of the infant's,
parent's and dyad's behaviour. The parental items comprise the parent's positive and negative
affect, expressed attitude toward the infant, sensitivity and contingent response to the infant's
cues, mirroring the infant's feeling, capacity to structure, behavioural involvement and
parental style. The infant items comprise expressed positive and negative affect and
characteristic mood, behaviour/adaptive abilities, activity level and communication skills. The
dyadic items comprise affective quality of interaction and mutuality of interaction.
All items were rated on a 5-point “Likert” scale. The scores 1 and 2 describe an area of
concern, the score 3 describes an area of some concern and the scores 4 and 5 describe an area
of strength. A trained coder made the assessment. The coder was unaware of the infant's
background and clinical status. Additionally, to estimate the interrater reliability from the
study data, 20% of all assessments were double-scored by another trained coder. The study
data was assessed by calculating the mean of the agreement percentage of the raters' overall
agreement. Agreement equal or above 80% is considered good, 50-80% is considered
moderate, and lower than 50% is considered poor. The mean of interrater agreements was
80.3% in six months PA and 81% in 18 months PA.
The PCERA items were organized in eight scales according to Clark [67] before the
data analysis: “Maternal positive affective involvement PS1”, “Maternal negative affect &
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behaviour PS2”, “Maternal intrusiveness PS3”, “Infant positive affect PS4”, “Infant quality
of play PS5”, “Infant dysregulation PS6”, “Dyadic mutuality & reciprocity PS7”, and “Dyadic
disorganization & tension PS8”. PCERA high scores (4-5) always indicate positive affect and
behaviour or lack of negative affect and behaviour. The Cronbach alpha coefficients for
calculating the internal consistency of PCERA subscales in our study were satisfactorily and
were .95,.86,.86, .90,.87,.85,.80,.86 for PS1-PS8 at six months PA (T2), and
.89,.81,.82,.92,.89,.75,.73,.79 for PS1-PS8 at 18 months PA (T3).
The PCERA scale has been used in several studies to explore the quality of preterm
mother-infant interactions.[25, 70-74]
Statistical methods
Values of continuous variables are presented as means (SD) or if skewed, as median
and range. Categorical variables are given as proportions and percentages. Paired-sample t-
test was used for comparison of the PCERA means scores at T2 and T3. Differences in the
quality of mother-infant interactions measured by the PCERA scales were explored with
independent-samples t-test. As grouping variable we used mothers’ clinical important case
scores (0=no, 1=yes) in IES, GHQ, STAI and the tentative diagnostic assessments at four time
points; two weeks PP (T0), two weeks after hospitalization (T1), six months PA (T2), and 18
months PA (T3) (Figure 2). A more detailed description of mothers’ clinical important case
scores in IES, GHQ, STAI and the tentative diagnostic assessments are available in our earlier
papers.[38, 39]
The correlations between normally distributed and continuous variables at T3 in
correlation analysis were measured using Pearson’s correlation coefficient or Spearman’s
correlation coefficient when the variables had a skewed distribution (Table 2).
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Forward linear regression analysis was used to identify possible predictors of the PCERA
results at T3 (Table 3). The three variables at T3 with the strongest bivariate associations
(<0.05) were included in the multivariable linear regression model. A careful check of the
model assumptions, including an investigation of residual plots, did not reveal any violation
of the assumptions. All analyses were performed in SPSS version 20. Two-sided statistical
tests were applied and a 5 % statistical significance level was chosen.
Ethics
Written informed consent was obtained from participants prior to the study start. The
study protocol was approved in 5 May 2005 and 19 April 2007 by the National Committee for
Research Ethics (S-05068 and S-07096b) and 1 April 2005 and 12 March 2007 by the Data
Inspectorate (12360 and 07/1088). The study protocol was carried out in accordance with the
Declaration of Helsinki.
For ethical reasons the mothers that reported clinically important mental health
problems were assessed and referred for adequate psychological treatment. In this study, we
looked for clinically important mental health problems in mothers at four points from the time
of birth to two years postpartum. A no referral procedure could have caused unnecessary
suffering for both mothers and children.
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RESULTS
Mother-Infant Interaction
The paired sample t-test of the results of the PCERA showed no significant difference
for the PCERA mean scores from six months to 18 months postterm age (PA). For that reason
the presented results are based only on the mean scores from 18 months PA. The results of the
PCERA revealed mean scores in three of the scales in the area of moderate concern and five
scales in the area of no concern (Table 2).
Differences in the quality of mother-infant interaction at T2 and T3 between mothers with or
without clinically important case scores at T0, T1, T2, and T3
The results of the independent-samples t-test showed significant group differences at
T2 and T3 between the mothers with clinically important case scores compared to mothers
without case scores in IES, GHQ, and tentative PTSR diagnosis at T0 (Figure 2). Mothers’
with clinical case scores at T3 in GHQ also showed significant better results at the .05 level
(2-tailed)* in two PCERA scales at T3; PS7 Dyadic mutuality and reciprocity (N0/N1=24/8,
mean 3.1/3.7*), and PS8 Dyadic disorganization and tension (N0/N1=24/8, mean 3.9/4.4*).
Most unexpectedly, the mothers with clinically important case scores (1=yes) at T0 showed
significantly better quality in mother-infant interaction in seven of the PCERA subscales at T3
than mothers with no (0=no) clinically important case scores (Figure 2). Tentative depression
or anxiety diagnosis (0=no, 1=yes) as a grouping variable showed no significant group
differences regarding the quality of the mother-infant interaction.
FIGURE 2 ABOUT HERE
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Psychometric means correlation with mother-infant interactional quality
In the bivariate correlation analyses, we revealed a positive correlation between better
interactional quality measured by PCERA and higher levels of maternal mental health
reactions measured by psychometric means at T3. High levels of GHQ Likert and clinical
case scores correlated with high levels of PCERA scores in three scales and GHQ case sum
scores correlated with two scales. High levels of STAI-X2 sum scores were associated with
high levels of PCERA scores in two scales and clinical case scores correlated with three
scales (Table 2).
Maternal and infant physical variables correlation with mother-infant interactional quality
Three maternal variables correlated with two of the PCERA scales. Parity (number of
previous births with child survival) and the scale “Maternal intrusiveness, intensity and
inconsistency (PS3)” were positively correlated. Family size (number of children in the
family) and the “Infant dysregulation and irritability (PS6)” scale inversely correlated. “Acute
caesarean” correlated positively with high scores on the same scale.
Two infant complications were correlated with two of the PCERA scales. Infant health
scores at the infant’s “Apgar scores at 5 minutes postpartum” correlated positively with the
“Infant quality of play, interest, and attention (PS5)” scale. Infant stroke by “Intraventricular
Haemorrhage grade 1 or 2 (IVH)” closely following birth” correlated inversely with the
“Maternal negative affect and behaviour (PS2)” scale (Table 2).
The strongest correlations were inversely and found between a pregnancy
complication “Bleeding in pregnancy” and the following six PCERA scales: “Maternal
negative affect and behaviour (PS2), Maternal intrusiveness, intensity, and inconsistency
(PS3), Infant positive affect, communicative, and social skills (PS4), Infant quality of play,
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interest, and attention (PS5), Dyadic mutuality and reciprocity (PS7), and Dyadic
disorganization and tension (PS8)”.
TABLE 2 ABOUT HERE
Predictors of preterm mother-infant interactional quality
In the multiple linear regression analyses we revealed that the pregnancy complication
variable “Bleeding in pregnancy” was a significant predictor (p<0.01) of lower scores in
preterm mother-infant interaction in six of the PCERA domains, including both of the Dyadic
scales (Table 3). Trait anxiety (STAI-X2) clinically important case and sum score are
significant predictors for higher quality in preterm mother-infant interaction in the “Maternal
positive affect domain (PS1)” (p<0.01) and in the “Maternal intrusiveness (PS3)” domain
(p<0.05), consecutively. Higher “Number of children in the family” predicts lower interaction
quality in the “Infant dysregulation and irritability (PS6)” scale (p<0.05). Adjusted R2 showed
that the predictors explain from 17 to 39 % of the variance in different PCERA scales.
TABLE 3 ABOUT HERE
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DISCUSSION
The study revealed significant associations between pregnancy and birth
complications, maternal postpartum mental health, and the quality of preterm mother-infant
interaction. The most surprising results in our study were the detection of “Bleeding in
pregnancy” as a predictor of lower quality in preterm mother-infant interaction in six of eight
PCERA scales and the association between high levels of maternal mental health problems
and better mother-infant interactional quality.
The predictor “Bleeding in pregnancy” is profoundly interesting. No other study has,
to our knowledge, revealed a physical complication in pregnancy that predicts the quality of
the preterm mother-infant interaction. In a previous paper, we detected that “Bleeding in
pregnancy” was a predictor of low levels in maternal mental health reactions, while
“Preeclampsia”, which is a sudden complication later in pregnancy, predicted high levels of
maternal mental health reactions following preterm birth. “Bleeding in pregnancy” could be
experienced as an early warning sign for possible pregnancy complications as it usually
occurs before 22 weeks of pregnancy.
Two questions now arise: is it possible to provide an existential explanation of why “Bleeding
in pregnancy” contributes to low levels of PCERA scores in preterm mother-infant
interaction? Could it be that the mother-to-be feels “Bleeding in pregnancy” as a near-loss
experience leaving her with the frightening impression that her child is at risk (in which case
the preterm birth confirms the fear of loss)? Given such an enduring threatening impression,
the mother can be expected to be anxious and alert, preventing her from relaxing and taking
pleasure in the mother-infant interaction, and rather inviting negative affect and intrusiveness
which may also entail dyadic disorganization and tension.
A mother experiencing a sudden preterm birth with infant survival and no serious early
warning signs is likely to have been quite “undisturbed” in her transition process to prepare
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for motherhood. A preterm birth may represent a very dangerous situation for both mother
and child where both may have risked death. When mother experiences hope for survival, we
may assume that a prior “undisturbed” transition process into motherhood is likely to increase
her efforts to attain the very best mother-infant interaction.
Most unexpectedly, our results showed that high levels of maternal mental health
problems following preterm birth were associated with better quality in preterm mother-infant
interaction. In regression analysis, we found that high levels of maternal trait anxiety (STAI-
X2) scores predicted better scores in two PCERA scales at T3. In the independent-samples t-
test, we revealed that mothers with clinically important case scores on IES, GHQ, STAI and
the tentative diagnoses of PTSR/PTSD at 2 weeks postpartum (T0) showed significantly
better quality in mother-infant interaction on six PCERA scales at six months (T2) and on five
PCERA scales at 18 months postterm age (T3). The STAI trait’s association with general
psychological distress following preterm birth has been reported in our previous papers.[38,
39] In addition, the STAI trait’s association with posttraumatic stress following term birth has
also been reported by another study.[75]
It is theoretically interesting that our results imply that high levels of maternal mental
distress improve the preterm mother–infant interaction. At first glance, this result seems to
contradict the well-known connection between high levels of maternal depression and high
risk mother-infant interactions.[25, 76-78] It should be noted that we found quite low
prevalence of depression among the mothers participating in this study.[38, 39] Instead, we
found high levels of posttraumatic stress reactions. PTSD following childbirth is
acknowledged by several researchers to be potentially different from PTSD following other
traumatic incidences.[31] The culturally positive connotation of giving birth, the mother-child
connection, the transition from pregnancy to birth, and the formal care setting the birth
incident takes place in are all matters that may have an impact on PTSD following preterm
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birth. Several studies have reported that many people experience positive psychological
growth after struggling with trauma.[79] Maternal posttraumatic stress reaction following
preterm birth is characterized by a prior physical trauma where survival of the mother and the
baby may be at risk. Is it possible that maternal posttraumatic stress reactions following
preterm birth helps the mother to focus her attention towards her premature baby’s wellbeing?
Our results may imply that the posttraumatic stress response activates and helps the mother
cope over time with a tremendously stressful situation, and furthermore helps her stimulate
the prematurely born child’s healthy development. Several studies support our view.[56-58,
60] Other studies that have explored maternal mental health reactions following preterm birth
and preterm mother-child interactions have reported results that contrast with our own.[36, 46,
73, 80] Studies that have used the PCERA scale in studying preterm dyads, however, did not
find depression to be a significant predictor of PCERA outcome at six, 12, or16 months
PA.[25, 71] On the other hand, they reported that high infant heart rate variety (HVR) after
feeding,[72] and higher frequency of naps had a positive impact on preterm mother-infant
interaction.[74]
The socio-demographic variable “Number of children in the family” predicted low
interactional quality in one of the PCERA scales. In our study, the mothers with preterm
babies that had siblings showed significantly lower scores in the “Infant dysregulation scale
(PS6)” in the PCERA. Our result is supported by two studies in the 1970’s and 1980’s that
found the preterm infant’s birth-order to affect the mother-child interaction.[81, 82] An
explanation for their results was the mother’s divided attention between the infant and other
siblings.
Strength/limitations
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The participants in this study came from well-defined geographic areas and both single
and multiple births were included consecutively in the study, thus minimizing selection bias.
Our sample was homogeneous in socio-economic background (SES).The mothers had higher
educational attainments, greater age and higher socioeconomic status, higher number of twins
and higher rate of previous psychological treatment than would be found in a typical
population of mothers who deliver preterm in our country. In this sample we found no
indication of significant differences in parental challenges between participants with
singletons or twins that needed to be addressed in the analysis. Besides the high prevalence of
earlier psychological treatment among the mothers in our sample, we found no other
indication of mental distress that had an impact on their psychosocial function in everyday life
before the actual preterm birth incident. Regarding research on quality of the preterm mother-
infant interaction, it has been considered that risk factors other than preterm birth itself may
have created bias / been sources of bias in many studies [40, 44, 83]. In our study, we have
controlled for high risk socio-economic backgrounds.
It is a limitation that the video-procedure of PCERA could not be followed for the four
dyads that were recorded in their homes and not in the clinic, as were the others. On the other
hand, these dyads would not have participated if the recordings were not made in their homes.
It is a limitation that interrater reliability was not checked for tentative clinical diagnosis. The
prediction model used in this study needs further validation by future studies.
CONCLUSIONS
Our results imply that pregnancy complications occurring early in the pregnancy may
affect the bonding process between the mother and her preterm infant long term. Early
intervention programs should be offered to mothers with early pregnancy complications to
support mother-infant interaction.
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Acknowledgements
The authors would like to thank the families that participated in the study, the staff of the
maternity ward at the neonatal intensive care unit at the National Hospital, Oslo and Sari
Ahlqvist-Björkroth who coded and Tanja Lipasti who recoded the PCERA data. In particular,
we want to thank the parents who participated in the study.
Contributorship statement
ARM initiated the study, collected, and organized the data. ARM and AHP performed the
statistical analyses. ARM, PN, SB, AHP and THD wrote the article.
Competing interests
We have no information of disclosure of interests.
Funding
This work was supported by the Centre for Child and Adolescent Mental Health, Eastern and
Southern Norway and the University College of Oslo and Akershus.
Data sharing statement
All authors have read and approved the final manuscript and have given their consent for
publication in BMJ Open.
Word count 3983
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5 mothers with 5 infants refused to
participate
*4 mothers out of lack of energy or
mental capacity or lack of time.
*1 mother refused to be videotaped
1 mother with 1 infant refused to
participate at T3 due to her working load
2 mothers with 2 infants refused to
participate at T1
*1 mother started to work
*1 mother and infant were
transferred to another Hospital
34 mothers with 40 infants assessed for
eligibility
29 mothers with 35 infants included at 2
weeks postpartum (T0) and examined for maternal mental health problems.
26 mothers with 32 infants included at 18
months post term age (T3) and examined for maternal mental health problems and
for dyadic interaction.
27 mothers with 33 infants included at 2
weeks after discharge from hospital (T1) and examined for maternal mental health
problems.
27 mothers with 33 infants included at 6
months post term age (T2) and examined for maternal mental health problems and
for dyadic interaction.
Figure 1. Inclusion and exclusion of mothers of preterm born babies
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Figure 2. Differences in the quality of mother – infant interaction at T2; 6 months post term age (PA) and T3; 18 moths PA for mothers with (N1) and mothers without (N0) case scores in
psychometric means of IES, GHQ, and STAI, and tentative PTSR diagnosis at T0; 2 weeks
postpartum. Interaction quality is measured by the mean values in the PCERA subscales.
2.9
3.4
3.9
4.4
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS1) Parental
Positive Affctive Involvement and
Verbalization for Mothers with or without
Case Score in IES, GHQ, STAI, and with or
without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16) T3*
GHQ, T2(T3):N1=27(27), N0=6(5) T2*
STAI-X1, T2(T3):N1=23(22), N0=10(10)
STAI-X2, T2(T3):N1=31(30), N0=2(2)
PTSR, T2(T3):N1=17(16), N0=16(16) T3*
3.6
4.1
4.6
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS2) Parental
Negative Affctive Involvement and
Verbalization for Mothers with or without
Case Score in IES, GHQ, STAI, and with or
without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5)
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2) T2***
PTSR, T2(T3):N1=17(16), N0=16(16)
2.8
3.3
3.8
4.3
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS3) Parental
Intrusiveness, Intensitivity, and Inconsistency
for Mothers with or without Case Score in IES,
GHQ, STAI, and with or without PTSR
diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5)
STAI-X1, T2(T3) N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2) T2**
PTSR, T2(T3):N1=17(16), N0=16(16) T2*
2
2.5
3
3.5
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS4) Infant
Positive Affect Communicative and Social
Skills for Mothers with or without Case Score
in IES, GHQ, STAI, and with or without PTSR
diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5) T2**
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2)
PTSR, T2(T3):N1=17(16), N0=16(16)
2.9
3.1
3.3
3.5
3.7
3.9
4.1
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS5) Infant
Quality of Play and Relatedness for Mothers
with or without Case Score in IES, GHQ, STAI,
and with or without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5)
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2) T3*
PTSR, T2(T3):N1=17(16), N0=16(16)
3.6
3.8
4
4.2
4.4
4.6
4.8
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS6) Infant
Dysregulation and Irritability for Mothers with
or without Case Score in IES, GHQ, STAI, and
with or without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5)
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3): N1=31(30), N0=2(2)
PTSR, T2(T3):N1=17(16), N0=16(16)
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N0 = the number of mothers without case scores in IES, GHQ, STAI and PTSR diagnosis at T0.
N1= the number of mothers with case scores in IES; GHQ; STAI and PTSR diagnosis.
*Significant difference at the .05 level (2-tailed) at the time referred to as T2 (6 months PA) or T3 (18 months PA).
**Significant difference at the .01 level (2-tailed) at the time referred to as T2 (6 months PA) or T3 (18 months PA).
*** Significant difference at the .001 level (2-tailed) at the time referred to as T2 (6 months PA) or T3 (18 months PA).
2.1
2.3
2.5
2.7
2.9
3.1
3.3
3.5
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS7) Dyadic
Mutuality and Reciprocity for Mothers with or
without Case Score in IES, GHQ, STAI, and with
or without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5) T2**
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2)
PTSR, T2(T3):N1=17(16), N0=16(16)
2.5
2.7
2.9
3.1
3.3
3.5
3.7
3.9
4.1
4.3
6 months PA
(T2) Case
18 months PA
(T3) Case
6 months PA
(T2) No Case
18 months PA
(T3) No Case
Mean PCERA subscale score in (PS8) Dyadic
Disorganization and Tension for Mothers
with or without Case Score in IES, GHQ, STAI,
and with or without PTSR diagnosis at T0.
IES, T2(T3):N1=17(16), N0=16(16)
GHQ, T2(T3):N1=27(27), N0=6 (5)
STAI-X1, T2(T3):N1=23(22), N0=10 (10)
STAI-X2, T2(T3):N1=31(30), N0=2(2) T2*
PTSR, T2(T3):N1=17(16), N0=16(16)
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Table 1. Socio-demographic, physical characteristics, and mental health variables in mothers
giving preterm birth and their children at two weeks postpartum (T0).
Mothers n=29
Age; mean (SD) 33.7 (4.3)
Education > 12 years; n (%) 26 (89.7)
Single parent; n (%) 0 (0)
Unemployed; n (%) 4 (13.8)
Previous psychological treatment; n (%)
8 (27.6)
Chronic illness; n (%) 2 (6.9)
Tot. no. of children; mean (SD) 1.7 (.8)
Previous pregnancies; mean (SD) 1.1 (1.5)
Previous childbirths; mean (SD) .5 (.7)
First time mothers; n (%) 18 (62.1)
IVFa pregnancy; n (%) 8 (27.6)
Bleeding in pregnancy; n (%) 19 (65.5)
Preeclampsia; n (%) 4 (14.3)
Caesarean; n (%) 17 (58.6)
Mental Health Variables:b
IES total (0-75); mean (SD) 19.7 (10.8)
IES Clinically significant case score >18; n (%) 13 (44.8)
GHQ Likert (0-90); n (%) 40 (15.4)
GHQ case (0-30): n (%) 12.8 (7.5)
GHQ Clinically important case score >5; n (%) 23 (79.3)
STAI-X1 (0-40); mean (SD) 21.5 (2.8)
STAI-X1 Clinically important case score >19; n (%) 20 (69)
STAI-X2 (0-80); mean (SD) 44.0 (4)
STAI-X2 Clinically important case score >39; n (%) 27 (93.1)
PTSR/PTSD Clinical diagnosis; n (%) 15 (51.7)
Children n=35
Girl; n (%) 17 (48.6)
Boy; n (%) 18 (51.4)
Twinc; n (%) 14 (40)
Gestational age (weeks);
Median (range)
Mean (SD)
29 (24-32)
28.5 (2.6)
Birth weight (kg);
Median (range)
Mean (SD)
1.2 (.6-2.0)
1.2 (.4)
Apgar score at 1 minute; median (SD) 6.3 (2.3)
Apgar score at 5 minutes; median (SD) 7.6 (2.0)
Apgar score at 10 minutes; median (SD) 8.3 (1.0)
Oxygen supply > 28 days; n (%) 19 (54)
IVHd; n (%) 7 (20.0)
a In vitro fertilization/Assisted fertilization.
bThe Impact of Event Scale (IES), The General Health Questionnaire (GHQ), The Spielberger State Trait Anxiety Inventory (STAI-X1/X2),
Tentative Clinical Diagnosis: Posttraumatic Stress Responses (PTSR), Posttraumatic Stress Disorder (PTSD).
cTwo of the twins were raised as singleton as their twin sibling were stillborn.
dIntraventricular hemorrhage grade 1-4 following birth.
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Table 2. Bivariate correlations at T3 (18 months post term age) between the PCERA scales, the maternal psychometric means, and the individual characteristics of the
mothers and infants. Pearson’s correlation coefficients (p<.05) are reported. (N=32). Mean values for PCERA subscales and 95% confidence interval for mean, are
reported in the last row of this table.
PCERA PS1
Maternal
Positive
affective
involvement
PCERA PS2
Maternal
Negative
affect &
behavior
PCERA PS3
Maternal
Intrusiveness
Insensitivity
Inconsistency
PCERA PS4
Infant
Positive affect
Communica-
tive & social
skills
PCERA PS5
Infant
Quality of
play
Interest
Attention
PCERA PS6
Infant
Dys-
regulation
Irritability
PCERA PS7
Dyadic
Mutuality
Reciprocity
PCERA PS8
Dyadic
Dis-
organization
Tension
GHQ Likert
sum score
.39*
.37*
.35* .16 .12 .05 .30 .28
GHQ case
sum score
.36* .36* .06 .12 .07 .17 .26 .31
GHQ
case > 5
.26 .40* .30 .33 .29 .21 .41* .43*
STAI-X2
sum score
.46** .21 .39*
.09 -.03 .08 .25 .19
STAI-X2
case > 39
.48* .36* .57** .19 .06 .07 .32 .32
Parity
.07
.18 .39* .24 .10
.01
.31 .33
CH< grade 3a
-.21 -.28 -.35* -.20 -.23 -.15 -.30 -.35
Apgar
at 5 minutes
-.01 .09 .20 .22 .35* -.12 .18 .19
Bleedings in
pregnancy
-.22 -.45** -.56** -.53** -.55** -.33 -.46** -.52**
Family sizeb
-.09 -.12 .07 -.02 -.16 -.45* .01 .00
Acute
Caesarean
.14 .14 .13 .01 .03 .39* .07 .22
Mean values
1-5 c(95% CI)
3.8 (3.6–4.1) 4.6 (4.4–4.8) 4.2 (4.0–4.4) 3.2 (2.9–3.5) 4.0 (3.7–4.2) 4.5 (4.4–4.7) 3.3 (3.0–3.5) 4.0 (3.8–4.2)
*Correlation is significant at the .05 level (2-tailed). **Correlation is significant at the .01 level (2-tailed). a CH< grade 3 refers to Cerebral Hemorrhage grade 1 or 2 closely after birth.
b Family size refers to the number of children in the family.
c Rates 1 and 2 in PCERA subscale; “Area of concern”. Rate 3 in PCERA subscale; “Area of moderate concern”. Rates 4 and 5 in PCERA subscale; “Area of no concern”.
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Table 3. Forward entry multiple regression analyses predicting mother-child interaction
outcomes for PCERA in preterm mother–child dyads at T3 (18 months post term age).
Unstandardized (B) and standardized (Beta) regression coefficients. (N=32)
Predicting variable B CI Beta P-
value
R2
adj.
PCERA:
Maternal positive aff-
ective involvement PS1
STAI-X2 clinical
important case score
.53 (.17, .89) .48 .005 .21
Maternal negative
affect & behavior PS2
Bleeding in pregnancy -.21 (-.37, -.06) -.45 .009 .18
Maternal intrusiveness
PS3
Bleeding in pregnancy
STAI-X2 total sum
-.29
.03
(-.45, -.13)
(.01, 06)
-.53
.35
.001
.017
.39
Infant positive affect
PS4
Bleeding in pregnancy -.43 (-.68, -.17) -.53 .002 .26
Infant quality of play
PS5
Bleeding in pregnancy -.35 (-.56, -.15) -.55 .001 .27
Infant dysregulation
PS6
Number of children in
the family
-.24
(-.42, -.06)
-.45
.011
.17
Dyadic mutuality &
reciprocity PS7
Bleeding in pregnancy
-.33
(-.56, -.09)
-.33
.008
.21
Dyadic disorganization
& tension PS8
Bleeding in pregnancy
-.32
(-.51, -.12)
-.52
.002
.25
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STROBE 2007 (v4) Statement—Checklist of items that should be included in reports of cohort studies
Section/Topic Item
# Recommendation Reported on page #
Title and abstract 1 (a) Indicate the study’s design with a commonly used term in the title or the abstract 1
(b) Provide in the abstract an informative and balanced summary of what was done and what was found 1
Introduction
Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 3-4
Objectives 3 State specific objectives, including any prespecified hypotheses 4
Methods
Study design 4 Present key elements of study design early in the paper 5
Setting 5 Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data
collection
5
Participants 6 (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up 5
(b) For matched studies, give matching criteria and number of exposed and unexposed
Variables 7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if
applicable
5-9
Data sources/
measurement
8* For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe
comparability of assessment methods if there is more than one group
5-9
Bias 9 Describe any efforts to address potential sources of bias 5 -9
Study size 10 Explain how the study size was arrived at 5
Quantitative variables 11 Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and
why
9-10
Statistical methods 12 (a) Describe all statistical methods, including those used to control for confounding 9-10
(b) Describe any methods used to examine subgroups and interactions 9-10
(c) Explain how missing data were addressed
(d) If applicable, explain how loss to follow-up was addressed
(e) Describe any sensitivity analyses
Results
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Participants 13* (a) Report numbers of individuals at each stage of study—eg numbers potentially eligible, examined for eligibility, confirmed
eligible, included in the study, completing follow-up, and analysed
5
(b) Give reasons for non-participation at each stage 5
(c) Consider use of a flow diagram 5
Descriptive data 14* (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential
confounders
5-7
(b) Indicate number of participants with missing data for each variable of interest
(c) Summarise follow-up time (eg, average and total amount) 5
Outcome data 15* Report numbers of outcome events or summary measures over time 5-9
Main results 16 (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, 95% confidence
interval). Make clear which confounders were adjusted for and why they were included
11-13
(b) Report category boundaries when continuous variables were categorized
(c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period
Other analyses 17 Report other analyses done—eg analyses of subgroups and interactions, and sensitivity analyses 11-13
Discussion
Key results 18 Summarise key results with reference to study objectives 14
Limitations
Interpretation 20 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from
similar studies, and other relevant evidence
2 and 16
Generalisability 21 Discuss the generalisability (external validity) of the study results 2
Other information
Funding 22 Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on
which the present article is based
18
*Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.
Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE
checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at
http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org.
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A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH REACTIONS,
PREGNANCY AND BIRTH COMPLICATIONS
Journal: BMJ Open
Manuscript ID bmjopen-2015-009699.R1
Article Type: Research
Date Submitted by the Author: 19-Oct-2015
Complete List of Authors: Misund, Aud R; University College of Oslo and Akershus, Health science Bråten, Stein; University of Oslo, Dept. of Sociology and Human Geography Nerdrum, Per; University College of Oslo and Akershus, Health science Pripp, Are; Oslo University Hospital, Department of Biostatistics, Epidemiology & Health Economy Diseth, Trond; Oslo University Hospital and University of Oslo, Department of Clinical Neurosciences for Children, Women and Children’s Division and Department of Medicine
<b>Primary Subject Heading</b>:
General practice / Family practice
Secondary Subject Heading: Mental health, Obstetrics and gynaecology, Reproductive medicine, Paediatrics
Keywords: Neonatal intensive & critical care < INTENSIVE & CRITICAL CARE, MENTAL HEALTH, Maternal medicine < OBSTETRICS, PERINATOLOGY, TRAUMA MANAGEMENT, Child & adolescent psychiatry < PSYCHIATRY
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1
A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH REACTIONS,
PREGNANCY AND BIRTH COMPLICATIONS
Aud R. Misund
1 Stein Bråten
Per Nerdrum
Are Hugo Pripp
Trond H. Diseth
ABSTRACT
Objective:
Pregnancy, birth and health complications, maternal mental health reactions following
preterm birth and their possible impact on early mother-infant interaction at six and 18
months corrected age (CA) were explored. Predictors of mother-infant interaction at 18
months CA were identified.
Design and methods:
This prospective longitudinal and observational study included 33 preterm mother-infant (<33
GA) interactions at six and 18 months CA from a socio-economic low risk middle class
sample. The parent-child early relational assessment scale (PCERA) was used to assess the
mother-infant interaction.
Results:
Mothers with case scores in the Impact of Event Scale, the General Health Questionnaire, the
Spielberger State/Trait Anxiety Inventory and PTSR/PTSD diagnosis at two weeks
postpartum (PP) showed significant better outcome than mothers without case scores in six
and two PCERA subscales at six months and 18 months CA, respectively.
“Bleeding in pregnancy” predicted lower quality in preterm mother-infant interaction in six
PCERA scales, while high “Maternal trait anxiety” predicted higher interactional quality in
1 Faculty of Health Sciences, University College of Oslo and Akershus and Department of Medicine, Institute of
Clinical Medicine, University of Oslo, adr: PO Box. 4 St. Olavs plass, N-0130 Oslo, Norway e-mail:
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2
two PCERA scales and “Family size” predicted lower interactional quality in one PCERA
scale at 18 months CA.
Conclusions:
Our study detected a correspondence between early pregnancy complications and lower
quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Strengths and limitations of this study:
The longitudinal design, the high response rate and the use of well-validated psychometric
instruments and interactional assessment tool are strengths in this study.
Fifty percent of the attending women received psychological treatment during the study and it
is a limitation that the influence of the psychological treatment on our study results was not
assessed.
The present study and describes a small preterm group and one should be cautious about
generalising from this study.
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INTRODUCTION
Early parent-infant relationships that are well functioning seem to be critical to
preterm children. Preterm children face severe risk of cognitive, emotional, and behavioural
disorders ,[1-8] and show more psychiatric symptoms in adolescence.[9] Early parent-infant
relationships that are well functioning seem to prevent and restore some of these difficulties in
preterm children.[10, 11]
Good quality in mother-child interactions have been reported to facilitate the infant’s
emotional, behavioural, cognitive, and neurobehavioral development.[12-17] The
interactional quality is also found to be related to the child’s physical health.[18, 19]
Compared with infants born at term the preterm infants are likely to show vague signals that
are difficult to read and respond to and are in need of extended care and support to gain self-
regulation. [20, 21] These traits, as well as parent’s psychiatric disease are known as risk
factors for good quality parent-infant interactions.[22, 23] Research detected significant
higher mental health reactions following preterm birth than term birth.[24-26]
The maternal stress reaction following preterm birth has been highlighted as a risk
factor in preterm dyads in several studies.[24-29] Postpartum depression has been identified
as predictor for interactional difficulties in term dyads[30] and reported as a risk factor for
difficulties in preterm mother-infant dyads.[31] Only a limited number of studies, however,
have explored the nature of mothers’ mental health reactions following preterm birth with
psychometric tools, and their impact on mother-infant interaction. Several studies, however,
have explored the postterm effect on maternal mental health.[32-36] Blom et al. interestingly
reported that certain perinatal complications such as preeclampsia, hospitalization, emergency
caesarean, and fetal distress predicted higher depression outcomes in a normal population
sample. An unaddressed trauma reaction is known to predispose for posttraumatic stress
disorder (PTSD) with long term effects on mothers’ mental health. The effect of mothers
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postpartum PTSD on mother-infant interaction and infant’s development is less explored.[37]
In addition only a limited number of studies have explored the maternal posttraumatic stress
responses following preterm birth[38-45] and their impact on mother-infant interactions.[20,
42, 46]
The results from preterm mother-infant interaction research are contradictory.
Different measurements and definitions being used, as well as the complexity of mother-
infant interactional studies may have contributed to these differences. Some studies have
reported that preterm mothers showed more stimulating behaviour and were emotionally
withdrawn, as well as non-synchronous in their interaction with the child,[20, 47-53] and
others have found no interactional differences between preterm and full term dyads.[20, 54-
59] Korja et al. detected that caregivers’ physical closeness with the infant was more
important to interactional quality than infants’ prematurity.[57] Finally, it is interesting that
several studies have shown that mothers are intensifying their efforts to be available and
supportive to their premature babies’ needs.[60-65] Preterm birth is reported to influence the
interaction between mother and infant.[20, 66, 67] The knowledge of risk factors that may
affect preterm mother-infant interaction is limited. [31, 68-70]The need for further exploration
of the complexity of factors influencing the early mother-infant relationship long-term in
preterm dyads seems essential.[6, 71]
The aim of our longitudinal study was to explore the possible influence of maternal
mental health reactions following preterm birth, pregnancy and birth complications, and their
impact on early preterm mother-infant interaction at six months PA and 18 months CA.
The first aim of our longitudinal study was to explore the associations between maternal
mental health reactions following preterm birth, pregnancy and birth complications, and early
preterm mother-infant interaction at six months PA (T2) and 18 months CA (T3). The second
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aim of the study was to identify predictors of early mother-infant interaction quality at T2 and
T3.
To our knowledge, these associations have not been explored in other studies.
Psychometric tools and tentative psychiatric diagnosis (anxiety, depression, and PTSR/PTSD)
were used to assess maternal mental health reactions following preterm birth.
It should be noted that this paper is an extension of our previous studies of short- and
long-term maternal mental health reactions following preterm birth.[44, 45]
METHOD
Participants
Data were collected in two periods: June 2005-January 2006 and October 2007-July
2008. The psychological responses of 29 consecutive mothers of 35 premature children born
before 33rd week of pregnancy were assessed at a high-specialized neonatal intensive care unit
(NICU) at Oslo University Hospital, Norway. Mothers of severely ill babies that the medical
staff estimated to have poor chance of survival, and non-Norwegian speakers were not
included. The participants stayed in NICU till they were discharged for home. The parents
could participate in the caring of the infant during hospitalisation. The data collection was
performed as soon as the mothers were able to attend an interview following preterm
childbirth: within two weeks postpartum (T0) median 11 days (4-30); then within two weeks
after hospitalization (T1), median time postpartum 2.7 months (0.2-4.7); then at the infant’s
six months corrected age (T2), median time postpartum 8.5 months (7.6-10.4); and at the
infant’s 18 months corrected age (T3), median time following birth 20.6 months (19.2-23.4).
Data collection of mother-infant interaction was collected only at T2 and T3. Mothers of
severely ill babies with uncertain survival and non-native speakers were not included (Figure
1).
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FIGURE 1 ABOUT HERE
Semi-structured interviews and standardized mental health screening questionnaires
were used to collect data about socio-demographics, the pregnancy and birth, child’s health
status, and mothers’ mental health reactions. Medical charts were used to double-check the
data of child’s health status, and pregnancy and birth. The studied sample was homogeneous
regarding high scores on socio-demographic variables such as education, income, and housing
standard. Most mothers were giving first time birth late in their twenties or early thirties. All
lived with the child’s father and none reported any relationship problems (Table 1).
The participating mothers’ mental health reactions following preterm birth have
been assessed at T0, T1, T2, T3 and methods and results are described in detail in our earlier
papers.[44, 45] Maternal mental health problems were assessed at every time points (T0, T1,
T2, T3) by standardized psychometric methods with well-established reliability and validity:
Impact of Event Scale (IES) 15-item version, one of the key psychometric assessment
methods in traumatic stress research,[72, 73] the General Health Questionnaire (GHQ) 30-
item version, a widely used screening instrument for assessing the presence of distress,
psychopathology and overall well-being,[74, 75] and the State/Trait Anxiety Inventory
(STAI-X1/X2)[76] is widely used to assess maternal anxiety. STAI-X1 measures state anxiety
levels reflecting subjective feelings of tension, apprehension, nervousness and worry. STAI-
X2 is a measure of trait anxiety that refers to individual differences in anxiety proneness, i.e.
in the tendency to see the world as dangerous and threatening, and the frequency with which
anxiety states are experienced. Scores above the threshold for identifying a psychiatric case is
referred to as a case score.
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Based on all information available in a clinical perusal of the psychometric self-reports
IES, GHQ and STAI of each of the 29 preterm mothers, and blinded to the physical and socio-
demographic characteristics of the mothers and their children, a tentative clinical diagnosis
was made where appropriate based on the clinical descriptions and diagnostic guidelines in
the ICD-10 Classification of mental and behavioural disorders, and was assessed by a
psychiatrist (last author).
A prevalence of maternal posttraumatic stress responses/disorders (PTSR/PTSD) two
weeks postpartum (T0) of 52% and maternal PTSD at 18 months corrected age (T3) of 23%
was revealed. On the other hand, depression was detected among 24 % of the mothers two
weeks postpartum and among 8% of the mothers at T3. Anxiety decreased from 7% at two
weeks postpartum to zero at T3.
Fourteen of the mothers received psychological support at the hospital during their
infants’ NICU stay. Eleven of these mothers were referred for further psychological treatment
after discharge from the hospital. Altogether, 20 mothers that met the criteria of clinical
diagnoses were referred for adequate psychological treatments such as psychotherapy,
psychopharmacology treatment, and mother-infant interactional treatment. Five of the
mothers refused the referral for psychological treatment, and only one of them filled the
criteria for a tentative clinical diagnosis (PTSD/Depression) at T3. The prevalence of
pregnancy and birth complications and maternal mental health reactions following preterm
birth are reported in earlier papers.[44, 45]
Data collected at 2 weeks postpartum (T0) about sociodemographics, physical
complications and maternal mental health reactions following preterm birth are presented in
Table 1.
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Table 1. Socio-demographic, physical characteristics, and mental health variables in mothers
giving preterm birth and their children at two weeks postpartum (T0).
Mothers n=29
Age; mean (SD) 33.7 (4.3)
Education > 12 years; n (%) 26 (89.7)
Single parent; n (%) 0 (0)
Unemployed; n (%) 4 (13.8)
Previous psychological treatment; n (%)
8 (27.6)
Chronic illness; n (%) 2 (6.9)
Tot. no. of children; median (quartile low,upper) 2 (1,2)
Previous pregnancies; median (quartile low,upper) 1 (0,2)
Previous childbirths; median (quartile low,upper) 0 (0,1)
First time mothers; n (%) 18 (62.1)
IVFa pregnancy; n (%) 8 (27.6)
Bleeding in pregnancy; n (%) 19 (65.5)
Preeclampsia; n (%) 4 (14.3)
Caesarean; n (%) 17 (58.6)
Mental Health Variables:b
IES total (0-75); median (quartile low,upper) 18 (11,30)
IES case score >18; n (%) 13 (44.8)
GHQ Likert score (0-90); n (%) 40 (15.4)
GHQ case (0-30): n (%) 12.8 (7.5)
GHQ case score >5; n (%) 23 (79.3)
STAI-X1 (0-40); mean (SD) 21.5 (2.8)
STAI-X1 case score >19; n (%) 20 (69)
STAI-X2 (0-80); mean (SD) 44.0 (4)
STAI-X2 case score >39; n (%) 27 (93.1)
PTSR Tentative clinical diagnosis; n (%) 15 (51.7)
Children n=35
Girl; n (%) 17 (48.6)
Boy; n (%) 18 (51.4)
Twinc; n (%) 14 (40)
Gestational age (weeks);
Median (range)
Mean (SD)
29 (24-32)
28.5 (2.6)
Birth weight (g);
Median (range)
Mean (SD)
1185(623-2030)
1222(423)
Apgar score at 1 minute; mean (SD) 6,3 (2.3)
Apgar score at 5 minute; mean (SD) 7.6 (2.0)
Apgar score at 10 minute; mean (SD) 8.3 (1.0)
Oxygen supply > 28 days; n (%) 19 (54)
IVHd; n (%) 7 (20.0) a In vitro fertilization/Assisted fertilization.
bThe Impact of Event Scale (IES) 15 item with scoring range 0(not at all) to 5 (very much), The General Health Questionnaire (GHQ)30 items
Likert scores with weights 0-1-2-3 and case scores with weights 0-0-1-1, The Spielberger State/Trait Anxiety Inventory (STAI-X1/X2) 10
item/20 item with scoring range 1-2-3-4. The STAI-X1 10 item was constructed since both STAI-X1 12 item and 20 item had been used and
only 10 items overlapped. Tentative Clinical Diagnosis: Posttraumatic Stress Responses (PTSR). cTwo of the twins were raised as singleton as their twin sibling were stillborn.
dIntraventricular hemorrhage grade 1-4 following birth.
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Measures
Mother–infant interaction in a free-play situation was video recorded at six and 18
months CA. According to Clark (1985) by six months of age, dyadic mutuality and dyadic
regulatory processes are perceptible while at 18 months, the infant's own communication
skills are easier to identify in interaction [77]. The interaction situation was recorded in a
consultation room at the psychiatric clinic for children and families situated in the same
building as the hospital the children were born in, except for four video recordings at 18
months CA that were recorded in their homes. The recordings were performed when child
was awaken and interested in a play session with mother. Recordings were stopped and
performed later when child became too distressed or sleepy to play. A therapist (first author)
instructed the mothers about the procedure. For the video recording, the mother and the infant
were placed on a soft mat with age-appropriate toys. Instructions by the investigators given to
the mother prior to the video recording were: ‘This is a free-play time with your child. You
can use the toys, or you can play without the toys. Try to play or be with your infant as you
usually would be”. Video recordings were obtained from all mother-infant pairs.
The recordings were five minutes long. The mother-infant interaction in the free-play
situation was analysed using the Parent-Child Early Relational Assessment (PCERA)
method.[77] The PCERA is developed to assess affective and behavioural aspects that both
the parent and infant bring into the interaction,[77] and the validity of the free play situation
has been established.[78, 79] Video recordings allows thoroughly analysis of the interactions
several times and in short and slow sections that can identify areas of strength and of concern
in the mother-infant interplay. The PCERA consists of 29 parental items, 28 infant items and
eight dyadic items. The assessment rates the frequency, duration and intensity of the infant's,
parent's and dyad's behaviour. The parental items comprise the parent's positive and negative
affect, expressed attitude toward the infant, sensitivity and contingent response to the infant's
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cues, mirroring the infant's feeling, capacity to structure, behavioural involvement and
parental style. The infant items comprise expressed positive and negative affect and
characteristic mood, behaviour/adaptive abilities, activity level and communication skills. The
dyadic items comprise affective quality of interaction and mutuality of interaction.
All items were rated on a 5-point “Likert” scale. The scores 1 and 2 describe an area of
concern, the score 3 describes an area of some concern and the scores 4 and 5 describe an area
of strength. A trained coder made the assessment. The coder was unaware of the infant's
background and clinical status. Additionally, to estimate the interrater reliability from the
study data, 20% of all assessments were double-scored by another trained coder. The study
data was assessed by calculating the mean of the agreement percentage of the raters' overall
agreement. Agreement equal or above 80% is considered good, 50-80% is considered
moderate, and lower than 50% is considered poor. The mean of interrater agreements was
80.3% in six months CA and 81% in 18 months CA.
The PCERA items were organized in eight scales according to Clark [77] before the
data analysis: “Maternal positive affective involvement PS1”, “Maternal negative affect &
behaviour PS2”, “Maternal intrusiveness PS3”, “Infant positive affect PS4”, “Infant quality
of play PS5”, “Infant dysregulation PS6”, “Dyadic mutuality & reciprocity PS7”, and “Dyadic
disorganization & tension PS8”. PCERA high scores (4-5) always indicate positive affect and
behaviour or lack of negative affect and behaviour. The Cronbach alpha coefficients for
calculating the internal consistency of PCERA subscales in our study were satisfactorily and
were .95,.86,.86, .90,.87,.85,.80,.86 for PS1-PS8 at six months CA (T2), and
.89,.81,.82,.92,.89,.75,.73,.79 for PS1-PS8 at 18 months CA (T3).
The PCERA scale has been used in several studies to explore the quality of preterm
mother-infant interactions.[31, 80-84]
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Statistical methods
Values of continuous variables are presented as means (SD) or if skewed, as median
and range. Categorical variables are given as proportions and percentages. Paired-sample t-
test was used for comparison of the PCERA means scores at T2 and T3. Differences in the
quality of mother-infant interactions measured by the PCERA scales were explored with
independent-samples t-test. As grouping variable we used mothers’ case scores (0=no, 1=yes)
in IES, GHQ, STAI and the tentative diagnostic assessments at four time points; two weeks
PP (T0), two weeks after hospitalization (T1), six months CA (T2), and 18 months CA (T3)
(Figure 2). A more detailed description of mothers’ case scores in IES, GHQ, STAI and the
tentative diagnostic assessments are available in our earlier papers.[44, 45]
The correlations between normally distributed and continuous variables at T3 in
correlation analysis were measured using Pearson’s correlation coefficient or Spearman’s
correlation coefficient when the variables had a skewed distribution (Table 2).
Forward linear regression analysis was used to identify possible predictors of the PCERA
results at T3 (Table 3). The three variables at T3 with the strongest bivariate associations
(<0.05) were included in the multivariable linear regression model; PS1 (STAI-X2 case,
STAI-X2 sum, GHQ Likert), PS2 (Bleeding in pregnancy, GHQ case, GHQ Likert), PS3
(STAI-X2 case, Bleeding in pregnancy, Parity/STAI-X2 sum), PS4 (Bleeding in pregnancy),
PS5 (Bleeding in pregnancy, Apgar 5 min), PS6 (Family size, Acute Caesarean), PS7
(Bleeding in pregnancy, GHQ case), and PS8 (Bleeding in pregnancy, GHQ case). A careful
check of the model assumptions, including an investigation of residual plots, did not reveal
any violation of the assumptions. All analyses were performed in SPSS version 20. Two-sided
statistical tests were applied and a 5 % statistical significance level was chosen.
Ethics
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Written informed consent was obtained from participants prior to the study start. The
study protocol was approved in 5 May 2005 and 19 April 2007 by the National Committee for
Research Ethics (S-05068 and S-07096b) and 1 April 2005 and 12 March 2007 by the Data
Inspectorate (12360 and 07/1088). The study protocol was carried out in accordance with the
Declaration of Helsinki.
For ethical reasons the mothers that reported mental health problems and had case
scores above the threshold for identifying a psychiatric case in IES, GHQ and STAI were
assessed and referred for adequate psychological treatment. In this study, we looked for
mental health problems in mothers at four points from the time of birth to two years
postpartum. A no referral procedure could have caused unnecessary suffering for both
mothers and children.
RESULTS
Associations between maternal mental health reactions following preterm birth,
pregnancy and birth complications, and early preterm mother-infant interaction at six
months PA (T2) and 18 months CA (T3)
The paired sample t-test of the results of the PCERA showed no significant difference
for the PCERA mean scores from six months to 18 months corrected age (CA). For that
reason the presented results from correlation and regression analysis are based only on the
mean scores from 18 months CA. The results of the PCERA revealed mean scores in three of
the scales in the area of moderate concern and five scales in the area of no concern. The
results of the PCERA is presented in Table 2.
Group differences in mother – infant interaction quality at T2 and T3 for mothers with and
without psychometric case scores at T0, T1, T2, and T3
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The results of the independent-samples t-test showed significant group differences at
T2 and T3 between the mothers with case scores above the threshold for identifying a
psychiatric case compared to mothers without case scores in IES, GHQ, and tentative PTSR
diagnosis at T0 (Figure 2). Mothers’ with case scores at T3 in GHQ also showed significant
better results at the .05 level (2-tailed)* in two PCERA scales at T3; PS7 Dyadic mutuality
and reciprocity (N0/N1=24/8, mean 3.1/3.7*), and PS8 Dyadic disorganization and tension
(N0/N1=24/8, mean 3.9/4.4*). Most unexpectedly, the mothers with case scores (1=yes) at T0
showed significantly better quality in mother-infant interaction in six (T2) and two (T3)
subscales of the PCERA than mothers with no (0=no) case scores (Figure 2). Tentative
depression or anxiety diagnosis (0=no, 1=yes) as a grouping variable showed no significant
group differences regarding the quality of the mother-infant interaction.
FIGURE 2 ABOUT HERE
Associations between maternal mental health reactions and mother-infant interactional
quality at T3
In the bivariate correlation analyses, we revealed a positive correlation between better
interactional quality measured by PCERA and higher levels of maternal mental health
reactions measured by psychometric means at T3. High levels of GHQ Likert and case scores
correlated with high levels of PCERA scores in three scales and GHQ case sum scores
correlated with two scales. High levels of STAI-X2 sum scores were associated with high
levels of PCERA scores in two scales and case scores correlated with three scales (Table 2).
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Associations between pregnancy/ birth complications, maternal variables and mother-infant
interactional quality at T3
The strongest correlations were inversely and found between a pregnancy
complication “Bleeding in pregnancy” and the following six PCERA scales: “Maternal
negative affect and behaviour (PS2), Maternal intrusiveness, intensity, and inconsistency
(PS3), Infant positive affect, communicative, and social skills (PS4), Infant quality of play,
interest, and attention (PS5), Dyadic mutuality and reciprocity (PS7), and Dyadic
disorganization and tension (PS8)”.
Two infant complications following birth were correlated with two of the PCERA
scales. Infant health scores at the infant’s “Apgar scores at 5 minutes postpartum” correlated
positively with the “Infant quality of play, interest, and attention (PS5)” scale. Infant stroke by
“Intraventricular Haemorrhage grade 1 or 2 (IVH)” closely following birth” correlated
inversely with the “Maternal negative affect and behaviour (PS2)” scale (Table 2).
Three maternal variables correlated with two of the PCERA scales. Parity (number of
previous births with child survival) and the scale “Maternal intrusiveness, intensity and
inconsistency (PS3)” were positively correlated. Family size (number of children in the
family) and the “Infant dysregulation and irritability (PS6)” scale inversely correlated. “Acute
caesarean” correlated positively with high scores on the same scale.
Associations between exposure variables, e.g. IVF treatment, pre-and postnatal
maternal health problems and pregnancy and birth/ postnatal complications, were not
significant.
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Table 2. Bivariate correlations at T3 (18 months corrected age) between the PCERA scales, the maternal
psychometric means, and the individual characteristics of the mothers and infants. Pearson’s correlation
coefficients (p<.05) are reported. (N=32). Mean values, range scores and minimum and maximum scores
for PCERA subscales are reported in the last row of this table.
PCERA
PS1
Maternal
Positive
affective
involve-
ment
PCERA
PS2
Maternal
Neg.
affect &
behav.
PCERA
PS3
Maternal
Intrusive-
ness
In-
sensitivit
y
Inconsist
-ency
PCERA
PS4
Infant
Positive
affect
Commun-
icative
& social
skills
PCERA
PS5
Infant
Quality of
play
Interest
Attention
PCERA
PS6
Infant
Dysregu-
lation
Irritabil-
ity
PCERA
PS7
Dyadic
Mutuali
ty
Reci-
procity
PCERA
PS8
Dyadic
Disorgan
-ization
Tension
GHQ Likert
sum score
.39*
.37*
.35* .16 .12 .05 .30 .28
GHQ case
sum score
.36* .36* .06 .12 .07 .17 .26 .31
GHQ
case > 5
.26 .40* .30 .33 .29 .21 .41* .43*
STAI-X2
sum score
.46** .21 .39*
.09 -.03 .08 .25 .19
STAI-X2
case > 39
.48* .36* .57** .19 .06 .07 .32 .32
Parity
.07
.18 .39* .24 .10
.01
.31 .33
CH< grade
3a
-.21 -.28 -.35* -.20 -.23 -.15 -.30 -.35
Apgar
at 5
minutes
-.01 .09 .20 .22 .35* -.12 .18 .19
Bleeding in
pregnancy
-.22 -.45** -.56** -.53** -.55** -.33 -.46** -.52**
Family
sizeb
-.09 -.12 .07 -.02 -.16 -.45* .01 .00
Acute
Caesarean
.14 .14 .13 .01 .03 .39* .07 .22
Mean/
Range c (Min-Max)
3.8/2.5
(2.3-4.8)
4.6/1.6
(3.4–5.0)
4.2/2.0
(3.0–5.0)
3.2/3.0
(1.9–4.9)
4.0/2.2
(2.7–4.9)
4.5/1.3
(3.7–5.0)
3.3/2.8
(2.0–
4.8)
4.0/2.0
(3.0–
5.0)
*Correlation is significant at the .05 level (2-tailed). **Correlation is significant at the .01 level (2-tailed). a CH< grade 3 refers to Cerebral Hemorrhage grade 1 or 2 closely after birth.
b Family size refers to the number
of children in the family. c Rates 1 and 2 in PCERA subscale; “Area of concern”. Rate 3 in PCERA subscale; “Area of moderate concern”.
Rates 4 and 5 in PCERA subscale; “Area of no concern”.
Predictors of mother-infant interactional quality at T3
In the multiple linear regression analyses we revealed that the pregnancy complication
variable “Bleeding in pregnancy” was a significant predictor (p<0.01) of lower scores in
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preterm mother-infant interaction in six of the PCERA domains, including both of the Dyadic
scales (Table 3). Trait anxiety (STAI-X2) case and sum score are significant predictors for
higher quality in preterm mother-infant interaction in the “Maternal positive affect domain
(PS1)” (p<0.01) and in the “Maternal intrusiveness (PS3)” domain (p<0.05), consecutively.
Higher “Number of children in the family” predicts lower interaction quality in the “Infant
dysregulation and irritability (PS6)” scale (p<0.05). Adjusted R2 showed that the predictors
explain from 17 to 39 % of the variance in different PCERA scales.
Table 3. Forward entry multiple regression analyses predicting mother-child interaction
outcomes for PCERA in preterm mother–child dyads at T3 (18 months corrected age).
Unstandardized (B) and standardized (Beta) regression coefficients. (N=32)
Predicting variable B CI Beta P-
value
R2
adj.
PCERA subscales:
PS1 (Maternal positive
affective involvement)
STAI-X2 case .53 (.17, .89) .48 .005 .21
PS2 (Maternal negative
affect & behavior)
Bleeding in pregnancy -.21 (-.37, -.06) -.45 .009 .18
PS3 (Maternal
intrusiveness)
Bleeding in pregnancy
STAI-X2 sum score
-.29
.03
(-.45, -.13)
(.01, 06)
-.53
.35
.001
.017
.39
PS4 (Infant positive
affect)
Bleeding in pregnancy -.43 (-.68, -.17) -.53 .002 .26
PS5 (Infant quality of
play)
Bleeding in pregnancy -.35 (-.56, -.15) -.55 .001 .27
PS6 (Infant
dysregulation)
Family size
-.24
(-.42, -.06)
-.45
.011
.17
PS7 (Dyadic mutuality &
reciprocity )
Bleeding in pregnancy
-.33
(-.56, -.09)
-.33
.008
.21
PS8 (Dyadic dis-
organization & tension)
Bleeding in pregnancy
-.32
(-.51, -.12)
-.52
.002
.25
PCERA subscales were used as dependent variables (Three variables with strongest bivariate association (<0.05) was used as
independent variables);
PS1 (STAI-X2 case, STAI-X2 sum score, GHQ Likert sum score), PS2 (Bleeding in pregnancy, GHQ case, GHQ Likert sum
score),PS3 (STAI-X2 case, Bleeding in pregnancy, Parity/STAI-X2 sum score), PS4 (Bleeding in pregnancy),
PS5 (Bleeding in pregnancy, Apgar at 5 minutes), PS6 (Family size, Acute Caesarean),
PS7 (Bleeding in pregnancy, GHQ case), PS8 (Bleeding in pregnancy, GHQ case).
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DISCUSSION
The study revealed significant associations between pregnancy and birth
complications, maternal postpartum mental health, and the quality of preterm mother-infant
interaction. The most surprising results in our study were the detection of “Bleeding in
pregnancy” as a predictor of lower quality in preterm mother-infant interaction in six of eight
PCERA scales, and the association between high levels of maternal mental health problems
and better mother-infant interactional quality. We should keep in mind that the results from a
small and explorative study have low statistical power. In most studies there also is a
possibility that confounding variables are not included in the analysis that should have been.
In our study that could have been assessment of mothers’ attachment patterns, the effect of
psychological assessment and referral procedure and an assessment of the comforting
conditions for mother-infant interactions in the hospital for instance. However, our study
results may be of value for future research that will systematically explore the complexity of
factors influencing early preterm mother-infant interaction in a broader sense.
The predictor “Bleeding in pregnancy” is profoundly interesting. No other study has,
to our knowledge, revealed a physical complication in pregnancy that predicts the quality of
the preterm mother-infant interaction. In a previous paper, we detected that “Bleeding in
pregnancy” was a predictor of low levels in maternal mental health reactions, while
“Preeclampsia”, which is a sudden complication later in pregnancy, predicted high levels of
maternal mental health reactions following preterm birth. “Bleeding in pregnancy” could be
experienced as an early warning sign for possible pregnancy complications as it usually
occurs before 22 weeks of pregnancy. “Bleeding in pregnancy” may therefore affect how
mother relates to her unborn child and how her transition into motherhood alternates.
Two questions now arise; is it possible to provide an existential explanation of why “Bleeding
in pregnancy” contributes to low levels of PCERA scores in preterm mother-infant
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interaction? Could it be that the mother-to-be feels “Bleeding in pregnancy” as a near-loss
experience leaving her with the frightening impression that her child is at risk (in which case
the preterm birth confirms the fear of loss)? Given such an enduring threatening impression,
the mother can be expected to be anxious and alert, preventing her from relaxing and taking
pleasure in the mother-infant interaction, and rather inviting negative affect and intrusiveness
which may also entail dyadic disorganization and tension. The greatest responsibility nature
has given us is to secure survival of our offspring Daniel Stern argues.[85]
A mother experiencing a sudden preterm birth with infant survival and no serious early
warning signs is likely to have been quite “undisturbed” in her transition process to prepare
for motherhood. A preterm birth may represent a very dangerous situation for both mother
and child where both may have risked death. When mother experiences hope for survival, we
may assume that a prior “undisturbed” transition process into motherhood is likely to increase
her efforts to attain the very best mother-infant interaction.
Attachment theory supports our hypothesis that loss or possible loss can be seen as serious
threats to attachment.[86] Attachment theory may also contribute with an alternative
explanation of our results. There is a growing number of research that show that mothers’
attachment pattern is associated with the mother-infant interaction.[87, 88] In our study,
however, attachment assessment were not explored.
Most unexpectedly, our results showed that high levels of maternal mental health
problems following preterm birth were associated with better quality in preterm mother-infant
interaction. In regression analysis, we found that high levels of maternal trait anxiety (STAI-
X2) scores predicted better scores in two PCERA scales at T3. In the independent-samples t-
test, we revealed that mothers with case scores on IES, GHQ, STAI and the tentative
diagnoses of PTSR/PTSD at 2 weeks postpartum (T0) showed significantly better quality in
mother-infant interaction on six PCERA scales at six months (T2) and on two PCERA scales
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at 18 months corrected age (T3). The STAI trait’s association with general psychological
distress following preterm birth has been reported in our previous papers.[44, 45] In addition,
the STAI trait’s association with posttraumatic stress following term birth has also been
reported by another study.[89]
It is theoretically interesting that our results imply that high levels of maternal mental
distress improve the preterm mother–infant interaction. At first glance, this result seems to
contradict the well-known connection between high levels of maternal depression and high
risk mother-infant interactions.[31, 90-92] It should be noted that we found quite low
prevalence of depression among the mothers participating in this study.[44, 45] Instead, we
found high levels of posttraumatic stress reactions. PTSD following childbirth is
acknowledged by several researchers to be potentially different from PTSD following other
traumatic incidences.[37] The culturally positive connotation of giving birth, the mother-child
connection, the transition from pregnancy to birth, and the formal care setting the birth
incident takes place in are all matters that may have an impact on PTSD following preterm
birth. Several studies have reported that many people experience positive psychological
growth after struggling with trauma.[93] Maternal posttraumatic stress reaction following
preterm birth is characterized by a prior physical trauma where survival of the mother and the
baby may be at risk. Is it possible that maternal posttraumatic stress reactions following
preterm birth helps the mother to focus her attention towards her premature baby’s wellbeing?
Our results may imply that the posttraumatic stress response activates and helps the mother
cope over time with a tremendously stressful situation, and furthermore helps her stimulate
the prematurely born child’s healthy development. Several studies support our view.[61-63,
65] Other studies that have explored maternal mental health reactions following preterm birth
and preterm mother-child interactions have reported results that contrast with our own.[42, 51,
83, 94] Studies that have used the PCERA scale in studying preterm dyads, however, did not
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find depression to be a significant predictor of PCERA outcome at six, 12, or16 months
CA.[31, 81] On the other hand, they reported that high infant heart rate variety (HVR) after
feeding,[82] and higher frequency of naps had a positive impact on preterm mother-infant
interaction.[84]
The socio-demographic variable “Family size” predicted low interactional quality in
one of the PCERA scales. In our study, the mothers with preterm babies that had siblings
showed significantly lower scores in the “Infant dysregulation scale (PS6)” in the PCERA.
Our result is supported by two studies in the 1970’s and 1980’s that found the preterm infant’s
birth-order to affect the mother-child interaction.[95, 96] An explanation for their results was
the mother’s divided attention between the infant and other siblings.
Strength/limitations
The participants in this study came from well-defined geographic areas and both single
and multiple births were included consecutively in the study, thus minimizing selection bias.
Our sample was homogeneous in socio-economic background (SES).The mothers had higher
educational attainments, greater age and higher socioeconomic status, higher number of twins
and higher rate of previous psychological treatment than would be found in a typical
population of mothers who deliver preterm in our country. In this sample we found no
indication of significant differences in parental challenges between participants with
singletons or twins that needed to be addressed in the analysis. Besides the high prevalence of
earlier psychological treatment among the mothers in our sample, no other collected data
gave indication for mental distress having an impact on their psychosocial function in
everyday life before the actual preterm birth incident. Regarding research on quality of the
preterm mother-infant interaction, it has been considered that risk factors other than preterm
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birth itself may have created bias / been sources of bias in many studies [20, 49, 97]. In our
study, we have controlled for high risk socio-economic backgrounds.
It is a limitation that the video-procedure of PCERA could not be followed for the four
dyads that were recorded in their homes and not in the clinic, as were the others. On the other
hand, these dyads would not have participated if the recordings were not made in their homes.
It is a limitation that interrater reliability was not checked for tentative clinical diagnosis. The
prediction model used in this study needs further validation by future studies.
CONCLUSIONS
Our results imply that pregnancy complications occurring early in the pregnancy may
affect the bonding process between the mother and her preterm infant long term. Early
intervention programs should be offered to mothers with early pregnancy complications to
support mother-infant interaction.
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Acknowledgements
The authors would like to thank the families that participated in the study, the staff of the
maternity ward at the neonatal intensive care unit at the National Hospital, Oslo and Sari
Ahlqvist-Björkroth who coded and Tanja Lipasti who recoded the PCERA data. In particular,
we want to thank the parents who participated in the study.
Contributorship statement
ARM initiated the study, collected, and organized the data. ARM and AHP performed the
statistical analyses. ARM, PN, SB, AHP and THD wrote the article.
Competing interests
We have no information of disclosure of interests.
Funding
This work was supported by the Centre for Child and Adolescent Mental Health, Eastern and
Southern Norway and the University College of Oslo and Akershus.
Data sharing statement
The full dataset is available from the corresponding author Aud R.
Misund([email protected]).
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85. Stern, D., N. Bruschweiler-Stern, and A. Freeland, The Birth of a Mother; How Motherhood
Changes You Forever. 1998, London Bloomsbury Publishing Plc.
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88. Coppola, G., R. Cassibba, and A. Costantini, What can make the difference?: Premature birth
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89. Czarnocka, J. and P. Slade, Prevalence and predictors of post-traumatic stress symptoms
following childbirth. British journal of clinical psychology, 2000. 39(1): p. 35-51.
90. Downey, G., Children of depressed parents: an integrative review. Psychological bulletin,
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92. Lovejoy, M.C., et al., Maternal depression and parenting behavior: A meta-analytic review.
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94. Feeley, N., L. Gottlieb, and P. Zelkowitz, Infant, Mother, and Contextual Predictors of Mother-
Very Low Birth Weight Infant Interaction at 9 Months of Age. Journal of Developmental &
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97. Wille, D.E., Relation of preterm birth with quality of infant--mother attachment at one year.
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STROBE 2007 (v4) Statement—Checklist of items that should be included in reports of cohort studies
Section/Topic Item
# Recommendation Reported on page #
Title and abstract 1 (a) Indicate the study’s design with a commonly used term in the title or the abstract 1
(b) Provide in the abstract an informative and balanced summary of what was done and what was found 1
Introduction
Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 3-4
Objectives 3 State specific objectives, including any prespecified hypotheses 4
Methods
Study design 4 Present key elements of study design early in the paper 5
Setting 5 Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data
collection
5
Participants 6 (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up 5
(b) For matched studies, give matching criteria and number of exposed and unexposed
Variables 7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if
applicable
5-9
Data sources/
measurement
8* For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe
comparability of assessment methods if there is more than one group
5-9
Bias 9 Describe any efforts to address potential sources of bias 5 -9
Study size 10 Explain how the study size was arrived at 5
Quantitative variables 11 Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and
why
9-10
Statistical methods 12 (a) Describe all statistical methods, including those used to control for confounding 9-10
(b) Describe any methods used to examine subgroups and interactions 9-10
(c) Explain how missing data were addressed
(d) If applicable, explain how loss to follow-up was addressed
(e) Describe any sensitivity analyses
Results
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Participants 13* (a) Report numbers of individuals at each stage of study—eg numbers potentially eligible, examined for eligibility, confirmed
eligible, included in the study, completing follow-up, and analysed
5
(b) Give reasons for non-participation at each stage 5
(c) Consider use of a flow diagram 5
Descriptive data 14* (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential
confounders
5-7
(b) Indicate number of participants with missing data for each variable of interest
(c) Summarise follow-up time (eg, average and total amount) 5
Outcome data 15* Report numbers of outcome events or summary measures over time 5-9
Main results 16 (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, 95% confidence
interval). Make clear which confounders were adjusted for and why they were included
11-13
(b) Report category boundaries when continuous variables were categorized
(c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period
Other analyses 17 Report other analyses done—eg analyses of subgroups and interactions, and sensitivity analyses 11-13
Discussion
Key results 18 Summarise key results with reference to study objectives 14
Limitations
Interpretation 20 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from
similar studies, and other relevant evidence
2 and 16
Generalisability 21 Discuss the generalisability (external validity) of the study results 2
Other information
Funding 22 Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on
which the present article is based
18
*Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.
Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE
checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at
http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org.
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A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH PROBLEMS,
PREGNANCY AND BIRTH COMPLICATIONS
Journal: BMJ Open
Manuscript ID bmjopen-2015-009699.R2
Article Type: Research
Date Submitted by the Author: 09-Dec-2015
Complete List of Authors: Misund, Aud R; University College of Oslo and Akershus, Health science Bråten, Stein; University of Oslo, Dept. of Sociology and Human Geography Nerdrum, Per; University College of Oslo and Akershus, Health science Pripp, Are; Oslo University Hospital, Department of Biostatistics, Epidemiology & Health Economy; University College of Oslo and Akershus, Faculty of Health Sciences Diseth, Trond; Oslo University Hospital and University of Oslo, Department of Clinical Neurosciences for Children, Women and Children’s Division and Department of Medicine
<b>Primary Subject Heading</b>:
General practice / Family practice
Secondary Subject Heading: Mental health, Obstetrics and gynaecology, Reproductive medicine, Paediatrics
Keywords: Neonatal intensive & critical care < INTENSIVE & CRITICAL CARE, MENTAL HEALTH, Maternal medicine < OBSTETRICS, PERINATOLOGY, TRAUMA MANAGEMENT, Child & adolescent psychiatry < PSYCHIATRY
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1
A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH PROBLEMS,
PREGNANCY AND BIRTH COMPLICATIONS
Aud R. Misund
1 Stein Bråten
Per Nerdrum
Are Hugo Pripp
Trond H. Diseth
ABSTRACT
Objective:
Pregnancy, birth and health complications, maternal mental health problems following
preterm birth and their possible impact on early mother-infant interaction at six and 18 months
corrected age (CA) were explored. Predictors of mother-infant interaction at 18 months CA
were identified.
Design and methods:
This prospective longitudinal and observational study included 33 preterm mother-infant (<33
GA) interactions at six and 18 months CA from a socio-economic low risk middle class
sample. The parent-child early relational assessment scale (PCERA) was used to assess the
mother-infant interaction.
Results:
“Bleeding in pregnancy” predicted lower quality in preterm mother-infant interaction in six
PCERA scales, while high “Maternal trait anxiety” predicted higher interactional quality in
two PCERA scales and “Family size” predicted lower interactional quality in one PCERA
scale at 18 months CA.
1 (Corresponding Author) Faculty of Health Sciences, University College of Oslo and Akershus and
Department of Medicine, Institute of Clinical Medicine, University of Oslo, adr: PO Box. 4 St. Olavs
plass, N-0130 Oslo, Norway e-mail:
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Mothers with symptoms of posttraumatic stress reactions, general psychological distress and
anxiety at two weeks postpartum (PP) showed significant better outcome than mothers
without symptoms in six PCERA subscales at six months CA and two PCERA subscales at18
months CA.
Conclusions:
Our study detected a correspondence between early pregnancy complications and lower
quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Strengths and limitations of this study:
The longitudinal design, the high response rate and the use of well-validated psychometric
instruments and interactional assessment tool are the strengths in this study.
Fifty percent of the attending women received psychological treatment during the study, and it
is a limitation that the influence of the psychological treatment on our study results was not
assessed.
The present study describes a small preterm group and one should be cautious about
generalising from this study.
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INTRODUCTION
Early parent-infant relationships that are well functioning seem to be critical to preterm
children. Preterm children face severe risk of cognitive, emotional, and behavioural disorders
,[1-8] and show more psychiatric symptoms in adolescence.[9] Early parent-infant
relationships that are well functioning seem to prevent and restore some of these difficulties in
preterm children.[10, 11] Good quality in mother-child interactions have been reported to
facilitate the infant’s emotional, behavioural, cognitive, and neurobehavioral
development.[12-17] The interactional quality is also found to be related to the child’s
physical health.[18, 19] Compared with infants born at term the preterm infants are likely to
show vague signals that are difficult to read and respond to and are in need of extended care
and support to gain self-regulation.[20, 21] These traits, as well as parent’s psychiatric disease
are known as risk factors for good quality parent-infant interactions.[22, 23] Research
detected significant higher mental health problems following preterm birth than term
birth.[24-26]
The maternal stress reaction following preterm birth has been highlighted as a risk
factor in preterm dyads in several studies.[24-29] Postpartum depression has been identified
as predictor for interactional difficulties in term dyads,[30] and reported as a risk factor for
difficulties in preterm mother-infant dyads.[31] Only a limited number of studies, however,
have explored the nature of mothers’ mental health problems following preterm birth with
psychometric tools, and their impact on mother-infant interaction. Several studies, however,
have explored the post-term effect on maternal mental health.[32-36] Blom et al. interestingly
reported that certain perinatal complications such as preeclampsia, hospitalization, emergency
caesarean, and fetal distress predicted higher depression outcomes in a normal population
sample.[36] An unaddressed trauma reaction is known to predispose for posttraumatic stress
disorder (PTSD) with long term effects on mothers’ mental health. The effect of mothers
postpartum PTSD on mother-infant interaction and infant’s development is less explored.[37]
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In addition only a limited number of studies have explored the maternal posttraumatic stress
responses following preterm birth,[38-45] and their impact on mother-infant interactions.[20,
42, 46]
The results from preterm mother-infant interaction research are contradictory.
Different measurements and definitions being used, as well as the complexity of mother-
infant interactional studies may have contributed to these differences. Some studies have
reported that preterm mothers showed more stimulating behaviour and were emotionally
withdrawn, as well as non-synchronous in their interaction with the child,[20, 21, 47-52] and
others have found no interactional differences between preterm and full term dyads.[20, 53-
58] Korja et al. detected that caregivers’ physical closeness with the infant was more
important to interactional quality than infants’ prematurity.[56] Finally, it is interesting that
several studies have shown that mothers are intensifying their efforts to be available and
supportive to their premature babies’ needs.[59-64] Preterm birth is reported to influence the
interaction between mother and infant.[20, 49, 65] The knowledge of risk factors that may
affect preterm mother-infant interaction is limited.[31, 66-68] The need for further exploration
of the complexity of factors influencing the early mother-infant relationship long-term in
preterm dyads seems essential.[6, 69]
The first aim of our longitudinal study was to explore the associations between
maternal mental health problems following preterm birth, pregnancy and birth complications,
and early preterm mother-infant interaction at six months CA (T2) and 18 months CA (T3).
The second aim of the study was to identify predictors of early mother-infant interaction
quality at T2 and T3.
To our knowledge, these associations have not been explored in other studies.
Psychometric tools and tentative psychiatric diagnosis (anxiety, depression, and PTSR/PTSD)
were used to assess maternal mental health problems following preterm birth.
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It should be noted that this paper is an extension of our previous studies of short- and
long-term maternal mental health problems following preterm birth.[44, 45]
METHOD
Participants
Data were collected in two periods: June 2005-January 2006 and October 2007-July
2008. The psychological responses of 29 consecutive mothers of 35 premature children born
before 33rd week of pregnancy were assessed at a high-specialized neonatal intensive care unit
(NICU) at Oslo University Hospital, Norway. Mothers of severely ill babies that the medical
staff estimated to have poor chance of survival, and non-Norwegian speakers were not
included. The participants stayed in NICU until they were discharged for home. The parents
could participate in the caring of the infant during hospitalisation. The data collection was
performed as soon as the mothers were able to attend an interview following preterm
childbirth: within two weeks postpartum (T0) median 11 days (4-30); then within two weeks
after hospitalization (T1), median time postpartum 2.7 months (0.2-4.7); then at the infant’s
six months corrected age (T2), median time postpartum 8.5 months (7.6-10.4); and at the
infant’s 18 months corrected age (T3), median time following birth 20.6 months (19.2-23.4).
Data collection of mother-infant interaction was collected only at T2 and T3. Mothers of
severely ill babies with uncertain survival and non-native speakers were not included (Figure
1).
Semi-structured interviews and standardized mental health screening questionnaires
were used to collect data about socio-demographics, the pregnancy and birth, child’s health
status, and mothers’ mental health problems. Medical charts were used to double-check the
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data of child’s health status, and pregnancy and birth. The studied sample was homogeneous
regarding high scores on socio-demographic variables such as education, income, and housing
standard. Most mothers were giving first time birth late in their twenties or early thirties. All
lived with the child’s father and none reported any relationship problems (Table 1). The
participating mothers’ mental health problems following preterm birth have been assessed at
T0, T1, T2, T3 and methods and results are described in detail in our earlier papers.[44, 45]
Maternal mental health problems were assessed at every time points (T0, T1, T2, T3) by
standardized psychometric methods with well-established reliability and validity: Impact of
Event Scale (IES) 15-item version, one of the key psychometric assessment methods in
traumatic stress research,[70, 71] the General Health Questionnaire (GHQ) 30item version, a
widely used screening instrument for assessing the presence of distress, psychopathology and
overall well-being,[72, 73] and the State/Trait Anxiety Inventory (STAI-X1/X2)[74] is widely
used to assess maternal anxiety. STAI-X1 measures state anxiety levels reflecting subjective
feelings of tension, apprehension, nervousness and worry. STAIX2 is a measure of trait
anxiety that refers to individual differences in anxiety proneness, i.e. in the tendency to see the
world as dangerous and threatening, and the frequency with which anxiety states are
experienced. Scores above the threshold for identifying a psychiatric case is referred to as a
case score.
Based on all information available in a clinical perusal of the psychometric self-reports
IES, GHQ and STAI of each of the 29 preterm mothers, and blinded to the physical and
sociodemographic characteristics of the mothers and their children, a tentative clinical
diagnosis was made where appropriate based on the clinical descriptions and diagnostic
guidelines in the ICD-10 Classification of mental and behavioural disorders, and was assessed
by a psychiatrist (last author).
A prevalence of maternal posttraumatic stress responses/disorders (PTSR/PTSD) two
weeks postpartum (T0) of 52% and maternal PTSD at 18 months corrected age (T3) of 23%
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was revealed. On the other hand, depression was detected among 24 % of the mothers two
weeks postpartum and among 8% of the mothers at T3. Anxiety decreased from 7% at two
weeks postpartum to zero at T3.
Fourteen of the mothers received psychological support at the hospital during their
infants’ NICU stay. Eleven of these mothers were referred for further psychological treatment
after discharge from the hospital. Altogether, 20 mothers that met the criteria of clinical
diagnoses were referred for adequate psychological treatments such as psychotherapy,
psychopharmacology treatment, and mother-infant interactional treatment. Five of the mothers
refused the referral for psychological treatment, and only one of them filled the criteria for a
tentative clinical diagnosis (PTSD/Depression) at T3. The prevalence of pregnancy and birth
complications and maternal mental health problems following preterm birth are reported in
earlier papers.[44, 45]
Data collected at 2 weeks postpartum (T0) about sociodemographics, physical
complications and maternal mental health problems following preterm birth are presented in
Table 1.
Table 1. Socio-demographic, physical characteristics, and mental health variables in mothers
giving preterm birth and their children at two weeks postpartum (T0).
Mothers n=29
Age; mean (SD) 33.7 (4.3)
Education > 12 years; n (%) 26 (89.7)
Single parent; n (%) 0 (0)
Unemployed; n (%) 4 (13.8)
Previous psychological treatment; n (%)
8 (27.6)
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Chronic illness; n (%) 2 (6.9)
Tot. no. of children; median (quartile low,upper) 2 (1,2)
Previous pregnancies; median (quartile low,upper) 1 (0,2)
Previous childbirths; median (quartile low,upper) 0 (0,1)
First time mothers; n (%) 18 (62.1)
IVFa pregnancy; n (%) 8 (27.6)
Bleeding in pregnancy; n (%) 19 (65.5)
Preeclampsia; n (%) 4 (14.3)
Caesarean; n (%) 17 (58.6)
Mental Health Variables:b
IES total (0-75); median (quartile low,upper) 18 (11,30)
IES case score >18; n (%) 13 (44.8)
GHQ Likert score (0-90); n (%) 40 (15.4)
GHQ case (0-30): n (%) 12.8 (7.5)
GHQ case score >5; n (%) 23 (79.3)
STAI-X1 (0-40); mean (SD) 21.5 (2.8)
STAI-X1 case score >19; n (%) 20 (69)
STAI-X2 (0-80); mean (SD) 44.0 (4)
STAI-X2 case score >39; n (%) 27 (93.1)
PTSR Tentative clinical diagnosis; n (%) 15 (51.7)
Children n=35
Girl; n (%) 17 (48.6)
Boy; n (%) 18 (51.4)
Twinc; n (%) 14 (40)
Gestational age (weeks);
Median (range)
Mean (SD)
29 (24-32)
28.5 (2.6)
Birth weight (g);
Median (range)
Mean (SD)
1185(623-2030)
1222(423)
Apgar score at 1 minute; mean (SD) 6,3 (2.3)
Apgar score at 5 minute; mean (SD) 7.6 (2.0)
Apgar score at 10 minute; mean (SD) 8.3 (1.0)
Oxygen supply > 28 days; n (%) 19 (54)
IVHd; n (%) 7 (20.0)
a In vitro fertilization/Assisted fertilization.
bThe Impact of Event Scale (IES) 15 item with scoring range 0(not at all) to 5 (very much), The General Health Questionnaire (GHQ)30 items
Likert scores with weights 0-1-2-3 and case scores with weights 0-0-1-1, The Spielberger State/Trait Anxiety Inventory (STAI-X1/X2) 10
item/20 item with scoring range 1-2-3-4. The STAI-X1 10 item was constructed since both STAI-X1 12 item and 20 item had been used and
only 10 items overlapped. Tentative Clinical Diagnosis: Posttraumatic Stress Responses (PTSR). cTwo of the twins were raised as singleton as their twin sibling were stillborn.
dIntraventricular hemorrhage grade 1-4 following birth.
Measures
Mother–infant interaction in a free-play situation was video recorded at six and 18
months CA. According to Clark (1985) by six months of age, dyadic mutuality and dyadic
regulatory processes are perceptible while at 18 months, the infant's own communication
skills are easier to identify in interaction.[75] The interaction situation was recorded in a
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consultation room at the psychiatric clinic for children and families situated in the same
building as the hospital the children were born in, except for four video recordings at 18
months CA that were recorded in their homes. The recordings were performed when child was
awaken and interested in a play session with mother. Recordings were stopped and performed
later when child became too distressed or sleepy to play. A therapist (first author) instructed
the mothers about the procedure. For the video recording, the mother and the infant were
placed on a soft mat with age-appropriate toys. Instructions by the investigators given to the
mother prior to the video recording were: “This is a free-play time with your child. You can
use the toys, or you can play without the toys. Try to play or be with your infant as you
usually would be”. Video recordings were obtained from all mother-infant pairs.
The recordings were five minutes long. The mother-infant interaction in the free-play
situation was analysed using the Parent-Child Early Relational Assessment (PCERA)
method.[75] The PCERA is developed to assess affective and behavioural aspects that both
the parent and infant bring into the interaction,[75] and the validity of the free play situation
has been established.[76, 77] Video recordings allows thoroughly analysis of the interactions
several times and in short and slow sections that can identify areas of strength and of concern
in the mother-infant interplay. The PCERA consists of 29 parental items, 28 infant items and
eight dyadic items. The assessment rates the frequency, duration and intensity of the infant's,
parent's and dyad's behaviour. The parental items comprise the parent's positive and negative
affect, expressed attitude toward the infant, sensitivity and contingent response to the infant's
cues, mirroring the infant's feeling, capacity to structure, behavioural involvement and
parental style. The infant items comprise expressed positive and negative affect and
characteristic mood, behaviour/adaptive abilities, activity level and communication skills. The
dyadic items comprise affective quality of interaction and mutuality of interaction.
All items were rated on a 5-point “Likert” scale. The scores 1 and 2 describe an area of
concern, the score 3 describes an area of some concern and the scores 4 and 5 describe an area
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of strength. A trained coder made the assessment. The coder was unaware of the infant's
background and clinical status. Additionally, to estimate the interrater reliability from the
study data, 20% of all assessments were double-scored by another trained coder. The study
data was assessed by calculating the mean of the agreement percentage of the raters' overall
agreement. Agreement equal or above 80% is considered good, 50-80% is considered
moderate, and lower than 50% is considered poor. The mean of interrater agreements was
80.3% in six months CA and 81% in 18 months CA.
The PCERA items were organized in eight scales according to Clark,[75] before the
data analysis: “Maternal positive affective involvement PS1”, “Maternal negative affect &
behaviour PS2”, “Maternal intrusiveness PS3”, “Infant positive affect PS4”, “Infant quality
of play PS5”, “Infant dysregulation PS6”, “Dyadic mutuality & reciprocity PS7”, and “Dyadic
disorganization & tension PS8”. PCERA high scores (4-5) always indicate positive affect and
behaviour or lack of negative affect and behaviour. The Cronbach alpha coefficients for
calculating the internal consistency of PCERA subscales in our study were satisfactorily and
were .95,.86,.86, .90,.87,.85,.80,.86 for PS1-PS8 at six months CA (T2), and
.89,.81,.82,.92,.89,.75,.73,.79 for PS1-PS8 at 18 months CA (T3).
The PCERA scale has been used in several studies to explore the quality of preterm
mother-infant interactions.[31, 78-82]
Statistical methods
Continuous variables are presented as means (SD) or if skewed, as median and range.
Categorical variables are given as proportions and percentages. Paired-sample t-test was used
for comparison of the PCERA means scores at T2 and T3. Differences in the quality of
mother-infant interactions measured by the PCERA scales were explored with independent-
samples t-test. As grouping variable we used mothers’ case scores above threshold for
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identifying psychiatric symptoms (0=no, 1=yes) in IES, GHQ, STAI and the tentative
diagnostic assessments at four time points; two weeks
PP (T0), two weeks after hospitalization (T1), six months CA (T2), and 18 months CA (T3)
(Figure 2). A more detailed description of mothers’ case scores in IES, GHQ, STAI and the
tentative diagnostic assessments are available in our earlier papers.[44, 45]
The association between variables at T3 were assessed using Pearson’s correlation
coefficient (Table 2).
Stepwise regression analysis with a forward selection method was used to identify possible
predictors of the PCERA results at T3 (Table 3). At most three variables at T3 with the
strongest bivariate associations above 0.3 were included in the multivariable linear regression
model; PS1 (STAI-X2 case, STAI-X2 sum, GHQ Likert), PS2 (Bleeding in pregnancy, GHQ
case, GHQ Likert), PS3 (STAI-X2 case, Bleeding in pregnancy, Parity/STAI-X2 sum), PS4
(Bleeding in pregnancy, GHQ case), PS5 (Bleeding in pregnancy, Apgar 5 min), PS6 (Family
size, Acute Caesarean, Bleeding in pregnancy), PS7 (Bleeding in pregnancy, GHQ case,
STAI-X2 case), and PS8 (Bleeding in pregnancy, GHQ case, CH<grade 3). A careful check of
the model assumptions, including an investigation of residual plots, did not reveal any
violation of the assumptions. All analyses were performed in SPSS version 20. Two-sided
statistical tests were applied and a 5 % statistical significance level was chosen.
Ethics
Written informed consent was obtained from participants prior to the study start. The
study protocol was approved in 5 May 2005 and 19 April 2007 by the National Committee for
Research Ethics (S-05068 and S-07096b) and 1 April 2005 and 12 March 2007 by the Data
Inspectorate (12360 and 07/1088). The study protocol was carried out in accordance with the
Declaration of Helsinki.
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For ethical reasons the mothers that reported mental health problems and had case
scores above the threshold for identifying psychiatric symptoms in IES, GHQ and STAI were
assessed and referred for adequate psychological treatment. In this study, we looked for
mental health problems in mothers at four points from the time of birth to two years
postpartum. A no referral procedure could have caused unnecessary suffering for both
mothers and children.
RESULTS
Associations between maternal mental health problems following preterm birth,
pregnancy and birth complications, and early preterm mother-infant interaction at six
months CA (T2) and 18 months CA (T3)
The paired sample t-test of the results of the PCERA showed no significant difference
for the PCERA mean scores from six months to 18 months corrected age (CA). For that
reason the presented results from correlation and regression analysis are based only on the
mean scores from 18 months CA. The results of the PCERA revealed mean scores in three of
the scales in the area of moderate concern and five scales in the area of no concern. The
results of the PCERA is presented in Table 2.
Group differences in mother – infant interaction quality at T2 and T3 for mothers with and
without psychometric case scores at T0, T1, T2, and T3
The results of the independent-samples t-test showed significant group differences at
T2 and T3 between the mothers with case scores above the threshold for identifying a
psychiatric case compared to mothers without case scores in IES, GHQ, and tentative PTSR
diagnosis at T0 (Figure 2). Mothers’ with case scores at T3 in GHQ also showed significant
better results at the .05 level (2-tailed)* in two PCERA scales at T3; PS7 Dyadic mutuality
and reciprocity (N0/N1=24/8, mean 3.1/3.7*), and PS8 Dyadic disorganization and tension
(N0/N1=24/8, mean 3.9/4.4*). Unexpectedly, the mothers with case scores (1=yes) at T0
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showed significantly better quality in mother-infant interaction in six (T2) and two (T3)
subscales of the PCERA than mothers with no (0=no) case scores (Figure 2). Tentative
depression or anxiety diagnosis (0=no, 1=yes) as a grouping variable showed no significant
group differences regarding the quality of the mother-infant interaction.
Associations between maternal mental health problems and mother-infant interactional
quality at T3
In the bivariate correlation analyses, we revealed a positive correlation between better
interactional quality measured by PCERA and higher levels of maternal mental health
problems measured by psychometric means at T3. High levels of GHQ Likert and case scores
correlated with high levels of PCERA scores in three scales and GHQ case sum scores
correlated with two scales. High levels of STAI-X2 sum scores were associated with high
levels of PCERA scores in two scales and case scores correlated with three scales (Table 2).
Associations between pregnancy/ birth complications, maternal variables and mother-infant
interactional quality at T3
The strongest correlations were inversely and found between a pregnancy complication
“Bleeding in pregnancy” and the following six PCERA scales: “Maternal negative affect and
behaviour (PS2), Maternal intrusiveness, intensity, and inconsistency (PS3), Infant positive
affect, communicative, and social skills (PS4), Infant quality of play, interest, and attention
(PS5), Dyadic mutuality and reciprocity (PS7), and Dyadic disorganization and tension
(PS8)”.
Two infant complications following birth were correlated with two of the PCERA
scales. Infant health scores at the infant’s “Apgar scores at 5 minutes postpartum” correlated
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positively with the “Infant quality of play, interest, and attention (PS5)” scale. Infant stroke by
“Intraventricular Haemorrhage grade 1 or 2 (IVH)” closely following birth” correlated
inversely with the “Maternal negative affect and behaviour (PS2)” scale (Table 2).
Three maternal variables correlated with two of the PCERA scales. Parity (number of
previous births with child survival) and the scale “Maternal intrusiveness, intensity and
inconsistency (PS3)” were positively correlated. Family size (number of children in the
family) and the “Infant dysregulation and irritability (PS6)” scale inversely correlated. “Acute
caesarean” correlated positively with high scores on the same scale.
Associations between exposure variables, e.g. IVF treatment, pre-and postnatal
maternal health problems and pregnancy and birth/postnatal complications, were not
significant.
Table 2. Pearson correlations coefficients at T3 (18 months corrected age) between the PCERA scales, the
maternal psychometric means, and the individual characteristics of the mothers and infants. (N=32). Mean
values, range scores and minimum and maximum scores for PCERA subscales are reported in the last
row of this table.
PCERA
PS1
Maternal Positive
affective
involvement
PCERA
PS2
Maternal
Negative
affect &
Behavior
PCERA PS3
Maternal Intrusiveness
Insensitivity
Inconsistency
PCERA PS4
Infant Positive affect Communicative
& Social skills
PCERA
PS5 Infant Quality of
play
Interest Attention
PCERA
PS6
Infant Dysregu -lation
Irritability
PCERA
PS7
Dyadic Mutuality
Reciprocity
PCERA
PS8
Dyadic Disorganization
Tension
GHQ Likert
sum score
.39*
.37*
.35* .16 .12 .05 .30 .28
GHQ case
sum score
.36* .36* .06 .12 .07 .17 .26 .31
GHQ
case > 5
.26 .40* .30 .33 .29 .21 .41* .43*
STAI-X2
sum score
.46** .21 .39*
.09 -.03 .08 .25 .19
STAI-X2
case > 39
.48* .36* .57** .19 .06 .07 .32 .32
Parity
.07
.18 .39* .24 .10
.01
.31 .33
CH< grade
3a
-.21 -.28 -.35* -.20 -.23 -.15 -.30 -.35
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Apgar
at 5
min.
-.01 .09 .20 .22 .35* -.12 .18 .19
Bleeding in
pregnancy
-.22 -.45** -.56** -.53** -.55** -.33 -.46** -.52**
Family
sizeb
-.09 -.12 .07 -.02 -.16 -.45* .01 .00
Acute
Caesarean
.14 .14 .13 .01 .03 .39* .07 .22
Mean/
Range c
(Min-Max)
3.8/2.5
(2.3-4.8)
4.6/1.6
(3.4–5.0)
4.2/2.0
(3.0–5.0)
3.2/3.0
(1.9–4.9)
4.0/2.2
(2.7–4.9)
4.5/1.3
(3.7–
5.0)
3.3/2.8
(2.0–4.8)
4.0/2.0
(3.0–5.0)
*Correlation is significant at the .05 level (2-tailed). **Correlation is significant at the .01 level (2-tailed). a CH< grade 3 refers to Cerebral Hemorrhage grade 1 or 2 closely after birth.
b Family size refers to the number
of children in the family. c Rates 1 and 2 in PCERA subscale; “Area of concern”. Rate 3 in PCERA subscale; “Area
of moderate concern”. Rates 4 and 5 in PCERA subscale; “Area of no concern”.
Predictors of mother-infant interactional quality at T3
In the multivariable linear regression analyses we revealed that the pregnancy
complication variable “Bleeding in pregnancy” was a significant predictor (p<0.01) of lower
scores in preterm mother-infant interaction in six of the PCERA domains, including both of
the Dyadic scales (Table 3). Trait anxiety (STAI-X2) case and sum score are significant
predictors for higher quality in preterm mother-infant interaction in the “Maternal positive
affect domain (PS1)” (p<0.01) and in the “Maternal intrusiveness (PS3)” domain (p<0.05),
consecutively. Higher “Number of children in the family” predicts lower interaction quality in
the “Infant dysregulation and irritability (PS6)” scale (p<0.05). Adjusted R2 showed that the
predictors explain from 17 to 39 % of the variance in different PCERA scales.
Table 3. Significant results of the multivariable regression analyses with the selected
independent variables to predict mother-child interaction following preterm birth at T3 (18
months corrected age). Unstandardized (B) and standardized (Beta) regression coefficients.
(N=32)
Predicting variable B CI Beta P value R2
adj.
PCERA subscales:
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PS1 (Maternal positive
affective involvement)
STAI-X2 case .53 (.17, .89) .48 .005 .21
PS2 (Maternal negative
affect & behavior)
Bleeding in pregnancy -.21 (-.37, -.06) -.45 .009 .18
PS3 (Maternal
intrusiveness)
Bleeding in pregnancy
STAI-X2 sum score
-.29
.03
(-.45, -.13)
(.01, 06)
-.53
.35
.001
.017
.39
PS4 (Infant positive
affect)
Bleeding in pregnancy -.43 (-.68, -.17) -.53 .002 .26
PS5 (Infant quality of
play)
Bleeding in pregnancy -.35 (-.56, -.15) -.55 .001 .27
PS6 (Infant
dysregulation)
Family size
-.24
(-.42, -.06)
-.45
.011
.17
PS7 (Dyadic mutuality &
reciprocity )
Bleeding in pregnancy
-.33
(-.56, -.09)
-.33
.008
.21
PS8 (Dyadic
disorganization &
tension)
Bleeding in pregnancy
-.32
(-.51, -.12)
-.52
.002
.25
PCERA subscales were used as dependent variables (At most three variables with strongest bivariate association above 0.3 were used as
independent variables); PS1 (STAI-X2 case, STAI-X2 sum score, GHQ Likert sum score), PS2 (Bleeding in pregnancy, GHQ case, GHQ Likert sum score),PS3
(STAI-X2 case, Bleeding in pregnancy, Parity/STAI-X2 sum score), PS4 (Bleeding in pregnancy), PS5 (Bleeding in pregnancy, Apgar at 5 minutes), PS6 (Family size, Acute Caesarean), PS7 (Bleeding in pregnancy, GHQ case), PS8 (Bleeding in pregnancy, GHQ case).
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DISCUSSION
The study revealed significant associations between pregnancy and birth
complications, maternal postpartum mental health, and the quality of preterm mother-infant
interaction. The most surprising results in our study were the detection of 1; “Bleeding in
pregnancy” as a predictor of lower quality in preterm mother-infant interaction in six of eight
PCERA scales, and 2; the association between high levels of maternal mental health problems
and better mother-infant interactional quality.
The predictor “Bleeding in pregnancy” is interesting. No other study has, to our
knowledge, revealed a physical complication in pregnancy that predicts a possible weaker
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quality of the mother-infant interaction following preterm birth. With reference to our
previous papers, “Bleeding in pregnancy”, was detected as a predictor of low levels in
maternal mental health symptoms, while, a sudden complication later in pregnancy
“Preeclampsia”, predicted high levels of maternal mental health problems following preterm
birth.[44, 45] As “Bleeding in pregnancy” usually occurs before 22 weeks of pregnancy it
may be experienced as an early warning sign for possible pregnancy complications by the
mother. A possible hypothesis may be that early complications in pregnancy and
complications late in pregnancy influence the mother differently in the way she relates to her
unborn child and how her transition into motherhood alternates. Early bleeding in pregnancy
could leave the mother-to-be with the impression that her child is at risk and when preterm
birth becomes reality, it may confirm her fear of loss. Given such an enduring threatening
impression, the mother can be expected to be anxious and alert, preventing her from relaxing
and taking pleasure in the mother-infant interaction, and rather initiating negative affect and
intrusiveness which may also entail dyadic disorganization and tension.
On the other hand, the mother without prior early warning signs is likely to have been
quite “undisturbed” in her transition process to prepare for motherhood until later in her
pregnancy. “Preeclampsia” and a sudden preterm birth induces a serious situation for both
mother and child and both may risk non-survival. When mother experiences hope for infant
survival, we may assume that a prior “undisturbed” transition process into motherhood is
likely to increase her efforts to attain the very best mother-infant interaction.
Attachment theory supports our hypothesis that loss or possible loss can be seen as
serious threats to attachment.[83] A growing number of research show that mothers’
attachment pattern is associated with the mother-infant interaction,[84, 85] and an assessment
of mothers’ attachment pattern would possibly have given a valuable perspective to our
results.
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Unexpectedly, our results showed that high levels of maternal mental health problems
following preterm birth were significantly associated with better quality in preterm mother-
infant interaction. In regression analysis, we found that high levels of maternal anxiety
measured by STAI-X2 predicted better mother-infant interaction in two PCERA scales at T3.
In our previous studies we found an association between STAI-X2 and general psychological
distress outcomes following preterm birth,[44, 45] and another study revealed an association
between STAI-X2 and posttraumatic stress outcomes following term birth.[86] With reference
to these studies we may suggest that there is an significant association between high levels of
mental health problems following preterm birth and better quality in two PCERA scales at T3.
In the independent-samples t-test, we also found that mothers with symptoms of posttraumatic
stress, general psychological distress and anxiety at 2 weeks postpartum (T0) showed
significantly better quality in mother-infant interaction on six PCERA scales at six months
(T2) and on two PCERA scales at 18 months corrected age (T3).
It is theoretically interesting that our results imply that high levels of maternal mental
distress improve the preterm mother–infant interaction. At first glance, this result seems to
contradict the well-known connection between high levels of maternal depression and high
risk mother-infant interactions.[31, 87-89] It should be noted that we found quite low
prevalence of depression among the mothers participating in this study.[44, 45] Instead, we
found high levels of posttraumatic stress reactions. PTSD following childbirth is
acknowledged by several researchers to be potentially different from PTSD following other
traumatic incidences.[37] The culturally positive connotation of giving birth, the mother-child
connection, the transition from pregnancy to giving birth, and the formal care setting the birth
incident takes place in are all matters that may have an impact on PTSD following preterm
birth. Several studies have reported that many people experience positive psychological
growth after struggling with trauma.[90, 91] Maternal posttraumatic stress reaction following
preterm birth is characterized by a prior physical trauma where survival of the mother and the
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baby may be at risk. Is it possible that maternal posttraumatic stress reactions following
preterm birth helps the mother to focus her attention towards her premature baby’s wellbeing?
Our findings may imply that the posttraumatic stress response activates and helps the mother
cope over time with a tremendously stressful situation, and furthermore helps her stimulate
the prematurely born child’s healthy development. Several studies support our view.[60-62,
64] However, other studies that have explored maternal mental health problems following
preterm birth and preterm mother-child interactions have reported results that contradict with
our findings.[42, 50, 81, 92] Studies that have used the PCERA scale in studying preterm
dyads, however, did not find depression to be a significant predictor of PCERA outcome at
six, 12, or 16 months CA.[31, 79] The socio-demographic variable “Family size” predicted
low interactional quality in one of the PCERA scales. In our study, the mothers with preterm
babies that had siblings showed significantly lower scores in the “Infant dysregulation scale
(PS6)” in the PCERA. Our result is supported by two studies in the 1970’s and 1980’s that
found the preterm infant’s birth-order to affect the mother-child interaction.[93, 94] An
explanation for their results was the mother’s divided attention between the infant and other
siblings.
Strength/limitations
The results from a small and explorative study have low statistical power and low
external validity,[95] and one should be cautious about generalising from the study. In most
studies there is also a possibility that confounding variables are not included in the analysis
that should have been. In our study such factors could have been assessment of mothers’
attachment patterns, the effect of psychological assessment and referral procedure and an
assessment of the comforting conditions for mother-infant interactions in the hospital.
However, our study results may still be of value for future research that will systematically
explore the complexity of factors influencing early preterm mother-infant interaction in a
broader sense.
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The participants in this study were included consecutively and both single and multiple
births were included, thus minimizing selection bias. Our sample was homogeneous in socio-
economic background (SES). However, the mothers had higher educational attainments,
greater age and higher socioeconomic status, higher number of twins and higher rate of
previous psychological treatment than would be found in a typical population of mothers who
deliver preterm in our country. In this sample we found no indication of significant
differences in parental challenges between participants with singletons or twins that needed to
be controlled for. Besides high prevalence of earlier psychological treatment among the
mothers in our sample, no other collected data indicated that mental distress had impact on
their psychosocial function in everyday life before the actual preterm birth incident.
Regarding research on quality of the preterm mother-infant interaction, it has been considered
that risk factors other than preterm birth itself have been sources of bias in many studies.[20,
48, 96] In our study, we have controlled for high risk socio-economic backgrounds.
It is a limitation that the video-procedure of PCERA could not be followed for the four
dyads that were recorded in their homes and not in the clinic, as were the others. On the other
hand, these dyads would not have participated if the recordings were not made in their homes.
It is a limitation that interrater reliability was not checked for tentative clinical diagnosis. The
prediction model used in this study needs further validation by future studies.
CONCLUSIONS
Our study detected a correspondence between early pregnancy complications and
lower quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Early intervention programs should be considered to mothers who give preterm birth to
support mother-infant interaction.
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Acknowledgements
The authors would like to thank the families that participated in the study, the staff of the
maternity ward at the neonatal intensive care unit at the National Hospital, Oslo and Sari
Ahlqvist-Björkroth who coded and Tanja Lipasti who recoded the PCERA data. In particular,
we want to thank the parents who participated in the study.
Contributorship statement
ARM initiated the study, collected, and organized the data. ARM and AHP performed the
statistical analyses. ARM, PN, SB, AHP and THD wrote the article.
Competing interests
We have no information of disclosure of interests.
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Funding
This work was supported by the Centre for Child and Adolescent Mental Health, Eastern and
Southern Norway and the University College of Oslo and Akershus.
Data sharing statement
The full data set is available from the corresponding author Aud R.
Misund([email protected]
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70. Sundin, E.C. and M.J. Horowitz, Horowitz's Impact of Event Scale Evaluation of 20
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72. Goldberg, D. and P. Williams, A user's guide to the general health questionnaire.
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73. Malt, U., The validity of the General Health Questionnaire in a sample of accidentally
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74. Spielberger, C.D., R.L. Goursch, and R.E. Luschene, STAI Manual for the State-Trait
Anxiety Inventory. 1970, California: Palo Alto: Consulting Psychologists Press.
75. Clark, R., The parent-child early relational assessment: Instrument and manual.
Madison: University of Wisconsin Medical School, Department of Psychiatry, 1985.
76. Clark, R., et al., Length of Maternity Leave and Quality of Mother-Infant Interactions.
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77. Clark, R., The Parent-Child Early Relational Assessment: A Factorial Validity Study.
Educational and Psychological Measurement, 1999. 59(5): p. 821-846.
78. Korja, R., et al., Relations between maternal attachment representations and the
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& Development, 2010. 33(3): p. 330-336.
79. McManus, B. and J. Poehlmann, Parent–child interaction, maternal depressive
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80. Schwichtenberg, A., et al., Daytime sleep and parenting interactions in infants born
preterm. Journal of Developmental and Behavioral Pediatrics, 2011. 32(1): p. 8-17.
81. Shah, P.E., M. Clements, and J. Poehlmann, Maternal Resolution of Grief After
Preterm Birth: Implications for Infant Attachment Security. Pediatrics, 2011. 127(2):
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82. Poehlmann, J., et al., Emerging self-regulation in toddlers born preterm or low birth
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2011. 23(1): p. 177-193.
83. Bowlby, J., Attachment and Loss: Volume 1: Attachment. Vol. 79. 1969. 1-401.
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84. Fonagy, P. and M. Target, Bridging the transmission gap: An end to an important
mystery of attachment research? Attachment & Human Development, 2005. 7(3): p.
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85. Coppola, G., R. Cassibba, and A. Costantini, What can make the difference?:
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organization, traumatic reaction and baby's medical risk. Infant Behavior and
Development, 2007. 30(4): p. 679-684.
86. Czarnocka, J. and P. Slade, Prevalence and predictors of post‐traumatic stress
symptoms following childbirth. British journal of clinical psychology, 2000. 39(1): p.
35-51.
87. Downey, G. and J.C. Coyne, Children of depressed parents: an integrative review.
Psychological bulletin, 1990. 108(1): p. 50.
88. Goodman, S.H. and I.H. Gotlib, Risk for psychopathology in the children of depressed
mothers: a developmental model for understanding mechanisms of transmission.
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89. Lovejoy, M.C., et al., Maternal depression and parenting behavior: A meta-analytic
review. Clinical Psychology Review, 2000. 20(5): p. 561-592.
90. Tedeschi, R.G., C.L. Park, and L.G. Calhoun, Posttraumatic growth: Conceptual
issues, in Posttraumatic growth: Positive changes in the afternath of crisis, R.G.
Tedeschi, C.L. Park, and L.G. Calhoun, Editors. 1998, Earlbaum: Mahwah, NJ. p. 1-
22.
91. Calhoun, L.G. and R.G. Tedeschi, The foundation of posttraumatic growth: An
expanded framework, in Handbook of posttraumatic growth: research and practice,
L.G. Calhoun and R.G. Tedeschi, Editors. 2006, Lawrence Erlbaum: Mahwah, New
York. p. 2-23.
92. Feeley, N., L. Gottlieb, and P. Zelkowitz, Infant, Mother, and Contextual Predictors
of Mother-Very Low Birth Weight Infant Interaction at 9 Months of Age. Journal of
Developmental & Behavioral Pediatrics, 2005. 26(1): p. 24-33.
93. Bendersky, M. and M. Lewis, The Impact of Birth Order on Mother-Infant
Interactions in Preterm and Sick Infants. Journal of Developmental & Behavioral
Pediatrics, 1986. 7(4): p. 242-246.
94. Cohen, S.E. and L. Beckwith, Caregiving Behaviors and Early Cognitive
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95. Kazdin, A.E., Research design in clinical psychology. 5th ed. 2013: Pearson New
International Edition.
96. Wille, D.E., Relation of preterm birth with quality of infant--mother attachment at one
year. Infant Behavior and Development, 1991. 14(2): p. 227-240.
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STROBE 2007 (v4) Statement—Checklist of items that should be included in reports of cohort studies
Section/Topic Item
# Recommendation Reported on page #
Title and abstract 1 (a) Indicate the study’s design with a commonly used term in the title or the abstract 1
(b) Provide in the abstract an informative and balanced summary of what was done and what was found 1
Introduction
Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 3-4
Objectives 3 State specific objectives, including any prespecified hypotheses 4
Methods
Study design 4 Present key elements of study design early in the paper 5
Setting 5 Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data
collection
5
Participants 6 (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up 5
(b) For matched studies, give matching criteria and number of exposed and unexposed
Variables 7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if
applicable
5-9
Data sources/
measurement
8* For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe
comparability of assessment methods if there is more than one group
5-9
Bias 9 Describe any efforts to address potential sources of bias 5 -9
Study size 10 Explain how the study size was arrived at 5
Quantitative variables 11 Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and
why
9-10
Statistical methods 12 (a) Describe all statistical methods, including those used to control for confounding 9-10
(b) Describe any methods used to examine subgroups and interactions 9-10
(c) Explain how missing data were addressed
(d) If applicable, explain how loss to follow-up was addressed
(e) Describe any sensitivity analyses
Results
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Participants 13* (a) Report numbers of individuals at each stage of study—eg numbers potentially eligible, examined for eligibility, confirmed
eligible, included in the study, completing follow-up, and analysed
5
(b) Give reasons for non-participation at each stage 5
(c) Consider use of a flow diagram 5
Descriptive data 14* (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential
confounders
5-7
(b) Indicate number of participants with missing data for each variable of interest
(c) Summarise follow-up time (eg, average and total amount) 5
Outcome data 15* Report numbers of outcome events or summary measures over time 5-9
Main results 16 (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, 95% confidence
interval). Make clear which confounders were adjusted for and why they were included
11-13
(b) Report category boundaries when continuous variables were categorized
(c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period
Other analyses 17 Report other analyses done—eg analyses of subgroups and interactions, and sensitivity analyses 11-13
Discussion
Key results 18 Summarise key results with reference to study objectives 14
Limitations
Interpretation 20 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from
similar studies, and other relevant evidence
2 and 16
Generalisability 21 Discuss the generalisability (external validity) of the study results 2
Other information
Funding 22 Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on
which the present article is based
18
*Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.
Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE
checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at
http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org.
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A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH PROBLEMS,
PREGNANCY AND BIRTH COMPLICATIONS
Journal: BMJ Open
Manuscript ID bmjopen-2015-009699.R3
Article Type: Research
Date Submitted by the Author: 12-Jan-2016
Complete List of Authors: Misund, Aud R; University College of Oslo and Akershus, Health science Bråten, Stein; University of Oslo, Dept. of Sociology and Human Geography Nerdrum, Per; University College of Oslo and Akershus, Health science Pripp, Are; Oslo University Hospital, Department of Biostatistics, Epidemiology & Health Economy; University College of Oslo and Akershus, Faculty of Health Sciences Diseth, Trond; Oslo University Hospital and University of Oslo, Department of Clinical Neurosciences for Children, Women and Children’s Division and Department of Medicine
<b>Primary Subject Heading</b>:
General practice / Family practice
Secondary Subject Heading: Mental health, Obstetrics and gynaecology, Reproductive medicine, Paediatrics
Keywords: Neonatal intensive & critical care < INTENSIVE & CRITICAL CARE, MENTAL HEALTH, Maternal medicine < OBSTETRICS, PERINATOLOGY, TRAUMA MANAGEMENT, Child & adolescent psychiatry < PSYCHIATRY
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1
A NORWEGIAN PROSPECTIVE STUDY OF PRETERM MOTHER-
INFANT INTERACTIONS AT SIX AND 18 MONTHS AND THE
IMPACT OF MATERNAL MENTAL HEALTH PROBLEMS,
PREGNANCY AND BIRTH COMPLICATIONS
Aud R. Misund
1 Stein Bråten
Per Nerdrum
Are Hugo Pripp
Trond H. Diseth
ABSTRACT
Objective:
Pregnancy, birth and health complications, maternal mental health problems following
preterm birth and their possible impact on early mother-infant interaction at six and 18 months
corrected age (CA) were explored. Predictors of mother-infant interaction at 18 months CA
were identified.
Design and methods:
This prospective longitudinal and observational study included 33 preterm mother-infant (<33
GA) interactions at six and 18 months CA from a socio-economic low risk middle class
sample. The parent-child early relational assessment scale (PCERA) was used to assess the
mother-infant interaction.
Results:
“Bleeding in pregnancy” predicted lower quality in preterm mother-infant interaction in six
PCERA scales, while high “Maternal trait anxiety” predicted higher interactional quality in
two PCERA scales and “Family size” predicted lower interactional quality in one PCERA
scale at 18 months CA.
1 Faculty of Health Sciences, University College of Oslo and Akershus and Department of Medicine,
Institute of Clinical Medicine, University of Oslo, adr: PO Box. 4 St. Olavs plass, N-0130 Oslo,
Norway e-mail:
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Mothers with symptoms of posttraumatic stress reactions, general psychological distress and
anxiety at two weeks postpartum (PP) showed significant better outcome than mothers
without symptoms in six PCERA subscales at six months CA and two PCERA subscales at18
months CA.
Conclusions:
Our study detected a correspondence between early pregnancy complications and lower
quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Strengths and limitations of this study:
The longitudinal design, the high response rate and the use of well-validated psychometric
instruments and interactional assessment tool are the strengths in this study.
Fifty percent of the attending women received psychological treatment during the study, and it
is a limitation that the influence of the psychological treatment on our study results was not
assessed.
The present study describes a small preterm group and one should be cautious about
generalising from this study.
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INTRODUCTION
Early parent-infant relationships that are well functioning seem to be critical to preterm
children. Preterm children face severe risk of cognitive, emotional, and behavioural disorders
,[1-8] and show more psychiatric symptoms in adolescence.[9] Early parent-infant
relationships that are well functioning seem to prevent and restore some of these difficulties in
preterm children.[10, 11] Good quality in mother-child interactions have been reported to
facilitate the infant’s emotional, behavioural, cognitive, and neurobehavioral
development.[12-17] The interactional quality is also found to be related to the child’s
physical health.[18, 19] Compared with infants born at term the preterm infants are likely to
show vague signals that are difficult to read and respond to and are in need of extended care
and support to gain self-regulation.[20, 21] These traits, as well as parent’s psychiatric disease
are known as risk factors for good quality parent-infant interactions.[22, 23] Research
detected significant higher mental health problems following preterm birth than term
birth.[24-26]
The maternal stress reaction following preterm birth has been highlighted as a risk
factor in preterm dyads in several studies.[24-29] Postpartum depression has been identified
as predictor for interactional difficulties in term dyads,[30] and reported as a risk factor for
difficulties in preterm mother-infant dyads.[31] Only a limited number of studies, however,
have explored the nature of mothers’ mental health problems following preterm birth with
psychometric tools, and their impact on mother-infant interaction. Several studies, however,
have explored the post-term effect on maternal mental health.[32-36] Blom et al. interestingly
reported that certain perinatal complications such as preeclampsia, hospitalization, emergency
caesarean, and fetal distress predicted higher depression outcomes in a normal population
sample.[36] An unaddressed trauma reaction is known to predispose for posttraumatic stress
disorder (PTSD) with long term effects on mothers’ mental health. The effect of mothers
postpartum PTSD on mother-infant interaction and infant’s development is less explored.[37]
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In addition only a limited number of studies have explored the maternal posttraumatic stress
responses following preterm birth,[38-45] and their impact on mother-infant interactions.[20,
42, 46]
The results from preterm mother-infant interaction research are contradictory.
Different measurements and definitions being used, as well as the complexity of mother-
infant interactional studies may have contributed to these differences. Some studies have
reported that preterm mothers showed more stimulating behaviour and were emotionally
withdrawn, as well as non-synchronous in their interaction with the child,[20, 21, 47-52] and
others have found no interactional differences between preterm and full term dyads.[20, 53-
58] Korja et al. detected that caregivers’ physical closeness with the infant was more
important to interactional quality than infants’ prematurity.[56] Finally, it is interesting that
several studies have shown that mothers are intensifying their efforts to be available and
supportive to their premature babies’ needs.[59-64] Preterm birth is reported to influence the
interaction between mother and infant.[20, 49, 65] The knowledge of risk factors that may
affect preterm mother-infant interaction is limited.[31, 66-68] The need for further exploration
of the complexity of factors influencing the early mother-infant relationship long-term in
preterm dyads seems essential.[6, 69]
The first aim of our longitudinal study was to explore the associations between
maternal mental health problems following preterm birth, pregnancy and birth complications,
and early preterm mother-infant interaction at six months CA (T2) and 18 months CA (T3).
The second aim of the study was to identify predictors of early mother-infant interaction
quality at T2 and T3.
To our knowledge, these associations have not been explored in other studies.
Psychometric tools and tentative psychiatric diagnosis (anxiety, depression, and PTSR/PTSD)
were used to assess maternal mental health problems following preterm birth.
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It should be noted that this paper is an extension of our previous studies of short- and
long-term maternal mental health problems following preterm birth.[44, 45]
METHOD
Participants
Data were collected in two periods: June 2005-January 2006 and October 2007-July
2008. The psychological responses of 29 consecutive mothers of 35 premature children born
before 33rd week of pregnancy were assessed at a high-specialized neonatal intensive care unit
(NICU) at Oslo University Hospital, Norway. Mothers of severely ill babies that the medical
staff estimated to have poor chance of survival, and non-Norwegian speakers were not
included. The participants stayed in NICU until they were discharged for home. The parents
could participate in the caring of the infant during hospitalisation. The data collection was
performed as soon as the mothers were able to attend an interview following preterm
childbirth: within two weeks postpartum (T0) median 11 days (4-30); then within two weeks
after hospitalization (T1), median time postpartum 2.7 months (0.2-4.7); then at the infant’s
six months corrected age (T2), median time postpartum 8.5 months (7.6-10.4); and at the
infant’s 18 months corrected age (T3), median time following birth 20.6 months (19.2-23.4).
Data collection of mother-infant interaction was collected only at T2 and T3. Mothers of
severely ill babies with uncertain survival and non-native speakers were not included (Figure
1).
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Semi-structured interviews and standardized mental health screening questionnaires
were used to collect data about socio-demographics, the pregnancy and birth, child’s health
status, and mothers’ mental health problems. Medical charts were used to double-check the
data of child’s health status, and pregnancy and birth. The studied sample was homogeneous
regarding high scores on socio-demographic variables such as education, income, and housing
standard. Most mothers were giving first time birth late in their twenties or early thirties. All
lived with the child’s father and none reported any relationship problems (Table 1). The
participating mothers’ mental health problems following preterm birth have been assessed at
T0, T1, T2, T3 and methods and results are described in detail in our earlier papers.[44, 45]
Maternal mental health problems were assessed at every time points (T0, T1, T2, T3) by
standardized psychometric methods with well-established reliability and validity: Impact of
Event Scale (IES) 15-item version, one of the key psychometric assessment methods in
traumatic stress research,[70, 71] the General Health Questionnaire (GHQ) 30item version, a
widely used screening instrument for assessing the presence of distress, psychopathology and
overall well-being,[72, 73] and the State/Trait Anxiety Inventory (STAI-X1/X2)[74] is widely
used to assess maternal anxiety. STAI-X1 measures state anxiety levels reflecting subjective
feelings of tension, apprehension, nervousness and worry. STAIX2 is a measure of trait
anxiety that refers to individual differences in anxiety proneness, i.e. in the tendency to see the
world as dangerous and threatening, and the frequency with which anxiety states are
experienced. Scores above the threshold for identifying a psychiatric case is referred to as a
case score.
Based on all information available in a clinical perusal of the psychometric self-reports
IES, GHQ and STAI of each of the 29 preterm mothers, and blinded to the physical and
sociodemographic characteristics of the mothers and their children, a tentative clinical
diagnosis was made where appropriate based on the clinical descriptions and diagnostic
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guidelines in the ICD-10 Classification of mental and behavioural disorders, and was assessed
by a psychiatrist (last author).
A prevalence of maternal posttraumatic stress responses/disorders (PTSR/PTSD) two
weeks postpartum (T0) of 52% and maternal PTSD at 18 months corrected age (T3) of 23%
was revealed. On the other hand, depression was detected among 24 % of the mothers two
weeks postpartum and among 8% of the mothers at T3. Anxiety decreased from 7% at two
weeks postpartum to zero at T3.
Fourteen of the mothers received psychological support at the hospital during their
infants’ NICU stay. Eleven of these mothers were referred for further psychological treatment
after discharge from the hospital. Altogether, 20 mothers that met the criteria of clinical
diagnoses were referred for adequate psychological treatments such as psychotherapy,
psychopharmacology treatment, and mother-infant interactional treatment. Five of the mothers
refused the referral for psychological treatment, and only one of them filled the criteria for a
tentative clinical diagnosis (PTSD/Depression) at T3. The prevalence of pregnancy and birth
complications and maternal mental health problems following preterm birth are reported in
earlier papers.[44, 45]
Data collected at 2 weeks postpartum (T0) about sociodemographics, physical
complications and maternal mental health problems following preterm birth are presented in
Table 1.
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Table 1. Socio-demographic, physical characteristics, and mental health variables in mothers
giving preterm birth and their children at two weeks postpartum (T0).
Mothers n=29
Age; mean (SD) 33.7 (4.3)
Education > 12 years; n (%) 26 (89.7)
Single parent; n (%) 0 (0)
Unemployed; n (%) 4 (13.8)
Previous psychological treatment; n (%)
8 (27.6)
Chronic illness; n (%) 2 (6.9)
Tot. no. of children; median (quartile low,upper) 2 (1,2)
Previous pregnancies; median (quartile low,upper) 1 (0,2)
Previous childbirths; median (quartile low,upper) 0 (0,1)
First time mothers; n (%) 18 (62.1)
IVFa pregnancy; n (%) 8 (27.6)
Bleeding in pregnancy; n (%) 19 (65.5)
Preeclampsia; n (%) 4 (14.3)
Caesarean; n (%) 17 (58.6)
Mental Health Variables:b
IES total (0-75); median (quartile low,upper) 18 (11,30)
IES case score >18; n (%) 13 (44.8)
GHQ Likert score (0-90); n (%) 40 (15.4)
GHQ case (0-30): n (%) 12.8 (7.5)
GHQ case score >5; n (%) 23 (79.3)
STAI-X1 (0-40); mean (SD) 21.5 (2.8)
STAI-X1 case score >19; n (%) 20 (69)
STAI-X2 (0-80); mean (SD) 44.0 (4)
STAI-X2 case score >39; n (%) 27 (93.1)
PTSR Tentative clinical diagnosis; n (%) 15 (51.7)
Children n=35
Girl; n (%) 17 (48.6)
Boy; n (%) 18 (51.4)
Twinc; n (%) 14 (40)
Gestational age (weeks);
Median (range)
Mean (SD)
29 (24-32)
28.5 (2.6)
Birth weight (g);
Median (range)
Mean (SD)
1185(623-2030)
1222(423)
Apgar score at 1 minute; mean (SD) 6,3 (2.3)
Apgar score at 5 minute; mean (SD) 7.6 (2.0)
Apgar score at 10 minute; mean (SD) 8.3 (1.0)
Oxygen supply > 28 days; n (%) 19 (54)
IVHd; n (%) 7 (20.0)
a In vitro fertilization/Assisted fertilization.
bThe Impact of Event Scale (IES) 15 item with scoring range 0(not at all) to 5 (very much), The General Health Questionnaire (GHQ)30 items
Likert scores with weights 0-1-2-3 and case scores with weights 0-0-1-1, The Spielberger State/Trait Anxiety Inventory (STAI-X1/X2) 10
item/20 item with scoring range 1-2-3-4. The STAI-X1 10 item was constructed since both STAI-X1 12 item and 20 item had been used and
only 10 items overlapped. Tentative Clinical Diagnosis: Posttraumatic Stress Responses (PTSR).
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cTwo of the twins were raised as singleton as their twin sibling were stillborn.
dIntraventricular hemorrhage grade 1-4 following birth.
Measures
Mother–infant interaction in a free-play situation was video recorded at six and 18
months CA. According to Clark (1985) by six months of age, dyadic mutuality and dyadic
regulatory processes are perceptible while at 18 months, the infant's own communication
skills are easier to identify in interaction.[75] The interaction situation was recorded in a
consultation room at the psychiatric clinic for children and families situated in the same
building as the hospital the children were born in, except for four video recordings at 18
months CA that were recorded in their homes. The recordings were performed when child was
awaken and interested in a play session with mother. Recordings were stopped and performed
later when child became too distressed or sleepy to play. A therapist (first author) instructed
the mothers about the procedure. For the video recording, the mother and the infant were
placed on a soft mat with age-appropriate toys. Instructions by the investigators given to the
mother prior to the video recording were: “This is a free-play time with your child. You can
use the toys, or you can play without the toys. Try to play or be with your infant as you
usually would be”. Video recordings were obtained from all mother-infant pairs.
The recordings were five minutes long. The mother-infant interaction in the free-play
situation was analysed using the Parent-Child Early Relational Assessment (PCERA)
method.[75] The PCERA is developed to assess affective and behavioural aspects that both
the parent and infant bring into the interaction,[75] and the validity of the free play situation
has been established.[76, 77] Video recordings allows thoroughly analysis of the interactions
several times and in short and slow sections that can identify areas of strength and of concern
in the mother-infant interplay. The PCERA consists of 29 parental items, 28 infant items and
eight dyadic items. The assessment rates the frequency, duration and intensity of the infant's,
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parent's and dyad's behaviour. The parental items comprise the parent's positive and negative
affect, expressed attitude toward the infant, sensitivity and contingent response to the infant's
cues, mirroring the infant's feeling, capacity to structure, behavioural involvement and
parental style. The infant items comprise expressed positive and negative affect and
characteristic mood, behaviour/adaptive abilities, activity level and communication skills. The
dyadic items comprise affective quality of interaction and mutuality of interaction.
All items were rated on a 5-point “Likert” scale. The scores 1 and 2 describe an area of
concern, the score 3 describes an area of some concern and the scores 4 and 5 describe an area
of strength. A trained coder made the assessment. The coder was unaware of the infant's
background and clinical status. Additionally, to estimate the interrater reliability from the
study data, 20% of all assessments were double-scored by another trained coder. The study
data was assessed by calculating the mean of the agreement percentage of the raters' overall
agreement. Agreement equal or above 80% is considered good, 50-80% is considered
moderate, and lower than 50% is considered poor. The mean of interrater agreements was
80.3% in six months CA and 81% in 18 months CA.
The PCERA items were organized in eight scales according to Clark,[75] before the
data analysis: “Maternal positive affective involvement PS1”, “Maternal negative affect &
behaviour PS2”, “Maternal intrusiveness PS3”, “Infant positive affect PS4”, “Infant quality
of play PS5”, “Infant dysregulation PS6”, “Dyadic mutuality & reciprocity PS7”, and “Dyadic
disorganization & tension PS8”. PCERA high scores (4-5) always indicate positive affect and
behaviour or lack of negative affect and behaviour. The Cronbach alpha coefficients for
calculating the internal consistency of PCERA subscales in our study were satisfactorily and
were .95,.86,.86, .90,.87,.85,.80,.86 for PS1-PS8 at six months CA (T2), and
.89,.81,.82,.92,.89,.75,.73,.79 for PS1-PS8 at 18 months CA (T3).
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The PCERA scale has been used in several studies to explore the quality of preterm
mother-infant interactions.[31, 78-82]
Statistical methods
Continuous variables are presented as means (SD) or if skewed, as median and range.
Categorical variables are given as proportions and percentages. Paired-sample t-test was used
for comparison of the PCERA means scores at T2 and T3. Differences in the quality of
mother-infant interactions measured by the PCERA scales were explored with independent-
samples t-test. As grouping variable we used mothers’ case scores above threshold for
identifying psychiatric symptoms (0=no, 1=yes) in IES, GHQ, STAI and the tentative
diagnostic assessments at four time points; two weeks PP (T0), two weeks after
hospitalization (T1), six months CA (T2), and 18 months CA (T3) (Figure 2a and 2b). A more
detailed description of mothers’ case scores in IES, GHQ, STAI and the tentative diagnostic
assessments are available in our earlier papers.[44, 45]
The association between variables at T3 were assessed using Pearson’s correlation
coefficient (Table 2).
Stepwise regression analysis with a forward selection method was used to identify possible
predictors of the PCERA results at T3 (Table 3). At most three variables at T3 with the
strongest bivariate associations above 0.3 were included in the multivariable linear regression
model; PS1 (STAI-X2 case, STAI-X2 sum, GHQ Likert), PS2 (Bleeding in pregnancy, GHQ
case, GHQ Likert), PS3 (STAI-X2 case, Bleeding in pregnancy, Parity/STAI-X2 sum), PS4
(Bleeding in pregnancy, GHQ case), PS5 (Bleeding in pregnancy, Apgar 5 min), PS6 (Family
size, Acute Caesarean, Bleeding in pregnancy), PS7 (Bleeding in pregnancy, GHQ case,
STAI-X2 case), and PS8 (Bleeding in pregnancy, GHQ case, CH<grade 3). A careful check of
the model assumptions, including an investigation of residual plots, did not reveal any
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violation of the assumptions. All analyses were performed in SPSS version 20. Two-sided
statistical tests were applied and a 5 % statistical significance level was chosen.
Ethics
Written informed consent was obtained from participants prior to the study start. The
study protocol was approved in 5 May 2005 and 19 April 2007 by the National Committee for
Research Ethics (S-05068 and S-07096b) and 1 April 2005 and 12 March 2007 by the Data
Inspectorate (12360 and 07/1088). The study protocol was carried out in accordance with the
Declaration of Helsinki.
For ethical reasons the mothers that reported mental health problems and had case
scores above the threshold for identifying psychiatric symptoms in IES, GHQ and STAI were
assessed and referred for adequate psychological treatment. In this study, we looked for
mental health problems in mothers at four points from the time of birth to two years
postpartum. A no referral procedure could have caused unnecessary suffering for both
mothers and children.
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RESULTS
Associations between maternal mental health problems following preterm birth,
pregnancy and birth complications, and early preterm mother-infant interaction at six
months CA (T2) and 18 months CA (T3)
The paired sample t-test of the results of the PCERA showed no significant difference
for the PCERA mean scores from six months to 18 months corrected age (CA). For that
reason the presented results from correlation and regression analysis are based only on the
mean scores from 18 months CA. The results of the PCERA revealed mean scores in three of
the scales in the area of moderate concern and five scales in the area of no concern. The
results of the PCERA is presented in Table 2.
Group differences in mother – infant interaction quality at T2 and T3 for mothers with and
without psychometric case scores at T0, T1, T2, and T3
The results of the independent-samples t-test showed significant group differences at
T2 and T3 between the mothers with case scores above the threshold for identifying a
psychiatric case compared to mothers without case scores; in IES that measure symptoms of
posttraumatic stress following preterm childbirth, in GHQ which measure symptoms of
general psychological distress, and in tentative PTSR diagnosis at T0 (Figure 2a and 2b).
Mothers’ identified with case scores of general psychological distress (GHQ) at T3 also
showed significant better results at the .05 level (2-tailed)* in two PCERA scales at T3; PS7
Dyadic mutuality and reciprocity (N0/N1=24/8, mean 3.1/3.7*), and PS8 Dyadic
disorganization and tension (N0/N1=24/8, mean 3.9/4.4*). Unexpectedly, the mothers with
case scores (1=yes) at T0 showed significantly better quality in mother-infant interaction in
six (T2) and two (T3) subscales of the PCERA than mothers with no (0=no) case scores
(Figure 2a and 2b). Tentative depression or anxiety diagnosis (0=no, 1=yes) as a grouping
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variable showed no significant group differences regarding the quality of the mother-infant
interaction.
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Associations between maternal mental health problems and mother-infant interactional
quality at T3
In the bivariate correlation analyses, we revealed a positive correlation between better
interactional quality measured by PCERA and higher levels of maternal mental health
problems measured by psychometric means at T3. High levels of maternal psychological
distress measured by GHQ Likert and case scores correlated with high levels of PCERA
scores in three scales and maternal psychological distress measured by GHQ case sum scores
correlated with two scales. High levels of maternal trait anxiety measured by STAI-X2 sum
scores were associated with high levels of PCERA scores in two scales and maternal trait
anxiety measured by STAI-X2 case scores correlated with three scales (Table 2).
Associations between pregnancy/ birth complications, maternal variables and mother-infant
interactional quality at T3
The strongest correlations were inversely and found between a pregnancy complication
“Bleeding in pregnancy” and the following six PCERA scales: “Maternal negative affect and
behaviour (PS2), Maternal intrusiveness, intensity, and inconsistency (PS3), Infant positive
affect, communicative, and social skills (PS4), Infant quality of play, interest, and attention
(PS5), Dyadic mutuality and reciprocity (PS7), and Dyadic disorganization and tension
(PS8)”.
Two infant complications following birth were correlated with two of the PCERA
scales. Infant health scores at the infant’s “Apgar scores at 5 minutes postpartum” correlated
positively with the “Infant quality of play, interest, and attention (PS5)” scale. Infant stroke by
“Intraventricular Haemorrhage grade 1 or 2 (IVH)” closely following birth” correlated
inversely with the “Maternal negative affect and behaviour (PS2)” scale (Table 2).
Three maternal variables correlated with two of the PCERA scales. Parity (number of
previous births with child survival) and the scale “Maternal intrusiveness, intensity and
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inconsistency (PS3)” were positively correlated. Family size (number of children in the
family) and the “Infant dysregulation and irritability (PS6)” scale inversely correlated. “Acute
caesarean” correlated positively with high scores on the same scale.
Associations between exposure variables, e.g. IVF treatment, pre-and postnatal
maternal health problems and pregnancy and birth/postnatal complications, were not
significant.
Table 2. Pearson correlations coefficients at T3 (18 months corrected age) between the PCERA scales, the
maternal psychometric means, and the individual characteristics of the mothers and infants. (N=32). Mean
values, range scores and minimum and maximum scores for PCERA subscales are reported in the last
row of this table.
PCERA
PS1
Maternal Positive
affective
involvement
PCERA
PS2
Maternal
Negative
affect &
Behavior
PCERA PS3
Maternal Intrusiveness
Insensitivity
Inconsistency
PCERA PS4
Infant Positive affect Communicative
& Social skills
PCERA
PS5 Infant Quality of
play
Interest Attention
PCERA
PS6
Infant Dysregu -lation
Irritability
PCERA
PS7
Dyadic Mutuality
Reciprocity
PCERA
PS8
Dyadic Disorganization
Tension
GHQ Likert
sum score .39*
.37*
.35* .16 .12 .05 .30 .28
GHQ case
sum score
.36* .36* .06 .12 .07 .17 .26 .31
GHQ
case > 5
.26 .40* .30 .33 .29 .21 .41* .43*
STAI-X2
sum score
.46** .21 .39*
.09 -.03 .08 .25 .19
STAI-X2
case > 39
.48* .36* .57** .19 .06 .07 .32 .32
Parity
.07
.18 .39* .24 .10
.01
.31 .33
CH< grade
3a
-.21 -.28 -.35* -.20 -.23 -.15 -.30 -.35
Apgar
at 5
min.
-.01 .09 .20 .22 .35* -.12 .18 .19
Bleeding in
pregnancy
-.22 -.45** -.56** -.53** -.55** -.33 -.46** -.52**
Family
sizeb
-.09 -.12 .07 -.02 -.16 -.45* .01 .00
Acute
Caesarean
.14 .14 .13 .01 .03 .39* .07 .22
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Mean/
Range c
(Min-Max)
3.8/2.5
(2.3-4.8)
4.6/1.6
(3.4–5.0)
4.2/2.0
(3.0–5.0)
3.2/3.0
(1.9–4.9)
4.0/2.2
(2.7–4.9)
4.5/1.3
(3.7–
5.0)
3.3/2.8
(2.0–4.8)
4.0/2.0
(3.0–5.0)
*Correlation is significant at the .05 level (2-tailed). **Correlation is significant at the .01 level (2-tailed).
a CH< grade 3 refers to Cerebral Hemorrhage grade 1 or 2 closely after birth.
b Family size refers to the number of children in the family.
c Rates 1 and 2 in PCERA subscale; “Area of concern”. Rate 3 in PCERA subscale; “Area of moderate concern”. Rates 4 and 5 in PCERA
subscale; “Area of no concern”.
Predictors of mother-infant interactional quality at T3
In the multivariable linear regression analyses we revealed that the pregnancy
complication variable “Bleeding in pregnancy” was a significant predictor (p<0.01) of lower
scores in preterm mother-infant interaction in six of the PCERA domains, including both of
the Dyadic scales (Table 3). Trait anxiety (STAI-X2) case and sum score are significant
predictors for higher quality in preterm mother-infant interaction in the “Maternal positive
affect domain (PS1)” (p<0.01) and in the “Maternal intrusiveness (PS3)” domain (p<0.05),
consecutively. Higher “Number of children in the family” predicts lower interaction quality in
the “Infant dysregulation and irritability (PS6)” scale (p<0.05). Adjusted R2 showed that the
predictors explain from 17 to 39 % of the variance in different PCERA scales.
Table 3. Significant results of the multivariable regression analyses with the selected
independent variables to predict mother-child interaction following preterm birth at T3 (18
months corrected age). Unstandardized (B) and standardized (Beta) regression coefficients.
(N=32)
Predicting variable B CI Beta P value R2
adj.
PCERA subscales:
PS1 (Maternal positive
affective involvement)
STAI-X2 case .53 (.17, .89) .48 .005 .21
PS2 (Maternal negative
affect & behavior)
Bleeding in pregnancy -.21 (-.37, -.06) -.45 .009 .18
PS3 (Maternal
intrusiveness)
Bleeding in pregnancy
STAI-X2 sum score
-.29
.03
(-.45, -.13)
(.01, 06)
-.53
.35
.001
.017
.39
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PS4 (Infant positive
affect)
Bleeding in pregnancy -.43 (-.68, -.17) -.53 .002 .26
PS5 (Infant quality of
play)
Bleeding in pregnancy -.35 (-.56, -.15) -.55 .001 .27
PS6 (Infant
dysregulation)
Family size
-.24
(-.42, -.06)
-.45
.011
.17
PS7 (Dyadic mutuality &
reciprocity )
Bleeding in pregnancy
-.33
(-.56, -.09)
-.33
.008
.21
PS8 (Dyadic
disorganization &
tension)
Bleeding in pregnancy
-.32
(-.51, -.12)
-.52
.002
.25
PCERA subscales were used as dependent variables (At most three variables with strongest bivariate association above 0.3 were used as
independent variables):
PS1 (STAI-X2 case, STAI-X2 sum score, GHQ Likert sum score), PS2 (Bleeding in pregnancy, GHQ case, GHQ Likert sum score),PS3 (STAI-X2
case, Bleeding in pregnancy, Parity/STAI-X2 sum score), PS4 (Bleeding in pregnancy), PS5 (Bleeding in pregnancy, Apgar at 5 minutes), PS6
(Family size, Acute Caesarean), PS7 (Bleeding in pregnancy, GHQ case), PS8 (Bleeding in pregnancy, GHQ case).
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DISCUSSION
The study revealed significant associations between pregnancy and birth
complications, maternal postpartum mental health, and the quality of preterm mother-infant
interaction. The most surprising results in our study were the detection of 1; “Bleeding in
pregnancy” as a predictor of lower quality in preterm mother-infant interaction in six of eight
PCERA scales, and 2; the association between high levels of maternal mental health problems
and better mother-infant interactional quality.
The predictor “Bleeding in pregnancy” is interesting. No other study has, to our
knowledge, revealed a physical complication in pregnancy that predicts a possible weaker
quality of the mother-infant interaction following preterm birth. With reference to our
previous papers, “Bleeding in pregnancy”, was detected as a predictor of low levels in
maternal mental health symptoms, while, a sudden complication later in pregnancy
“Preeclampsia”, predicted high levels of maternal mental health problems following preterm
birth.[44, 45] As “Bleeding in pregnancy” usually occurs before 22 weeks of pregnancy it
may be experienced as an early warning sign for possible pregnancy complications by the
mother. A possible hypothesis may be that early complications in pregnancy and
complications late in pregnancy influence the mother differently in the way she relates to her
unborn child and how her transition into motherhood alternates. Early bleeding in pregnancy
could leave the mother-to-be with the impression that her child is at risk and when preterm
birth becomes reality, it may confirm her fear of loss. Given such an enduring threatening
impression, the mother can be expected to be anxious and alert, preventing her from relaxing
and taking pleasure in the mother-infant interaction, and rather initiating negative affect and
intrusiveness which may also entail dyadic disorganization and tension.
On the other hand, the mother without prior early warning signs is likely to have been
quite “undisturbed” in her transition process to prepare for motherhood until later in her
pregnancy. “Preeclampsia” and a sudden preterm birth induces a serious situation for both
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mother and child and both may risk non-survival. When mother experiences hope for infant
survival, we may assume that a prior “undisturbed” transition process into motherhood is
likely to increase her efforts to attain the very best mother-infant interaction.
Attachment theory supports our hypothesis that loss or possible loss can be seen as
serious threats to attachment.[83] A growing number of research show that mothers’
attachment pattern is associated with the mother-infant interaction,[84, 85] and an assessment
of mothers’ attachment pattern would possibly have given a valuable perspective to our
results.
Unexpectedly, our results showed that high levels of maternal mental health problems
following preterm birth were significantly associated with better quality in preterm mother-
infant interaction. In regression analysis, we found that high levels of maternal anxiety
measured by STAI-X2 predicted better mother-infant interaction in two PCERA scales at T3.
In our previous studies we found an association between STAI-X2 and general psychological
distress outcomes following preterm birth,[44, 45] and another study revealed an association
between STAI-X2 and posttraumatic stress outcomes following term birth.[86] With reference
to these studies we may suggest that there is an significant association between high levels of
mental health problems following preterm birth and better quality in two PCERA scales at T3.
In the independent-samples t-test, we also found that mothers with symptoms of posttraumatic
stress, general psychological distress and anxiety at 2 weeks postpartum (T0) showed
significantly better quality in mother-infant interaction on six PCERA scales at six months
(T2) and on two PCERA scales at 18 months corrected age (T3).
It is theoretically interesting that our results imply that high levels of maternal mental
distress improve the preterm mother–infant interaction. At first glance, this result seems to
contradict the well-known connection between high levels of maternal depression and high
risk mother-infant interactions.[31, 87-89] It should be noted that we found quite low
prevalence of depression among the mothers participating in this study.[44, 45] Instead, we
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found high levels of posttraumatic stress reactions. PTSD following childbirth is
acknowledged by several researchers to be potentially different from PTSD following other
traumatic incidences.[37] The culturally positive connotation of giving birth, the mother-child
connection, the transition from pregnancy to giving birth, and the formal care setting the birth
incident takes place in are all matters that may have an impact on PTSD following preterm
birth. Several studies have reported that many people experience positive psychological
growth after struggling with trauma.[90, 91] Maternal posttraumatic stress reaction following
preterm birth is characterized by a prior physical trauma where survival of the mother and the
baby may be at risk. Is it possible that maternal posttraumatic stress reactions following
preterm birth helps the mother to focus her attention towards her premature baby’s wellbeing?
Our findings may imply that the posttraumatic stress response activates and helps the mother
cope over time with a tremendously stressful situation, and furthermore helps her stimulate
the prematurely born child’s healthy development. Several studies support our view.[60-62,
64] However, other studies that have explored maternal mental health problems following
preterm birth and preterm mother-child interactions have reported results that contradict with
our findings.[42, 50, 81, 92] Studies that have used the PCERA scale in studying preterm
dyads, however, did not find depression to be a significant predictor of PCERA outcome at
six, 12, or 16 months CA.[31, 79] The socio-demographic variable “Family size” predicted
low interactional quality in one of the PCERA scales. In our study, the mothers with preterm
babies that had siblings showed significantly lower scores in the “Infant dysregulation scale
(PS6)” in the PCERA. Our result is supported by two studies in the 1970’s and 1980’s that
found the preterm infant’s birth-order to affect the mother-child interaction.[93, 94] An
explanation for their results was the mother’s divided attention between the infant and other
siblings.
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Strength/limitations
The results from a small and explorative study have low statistical power and low
external validity,[95] and one should be cautious about generalising from the study. In most
studies there is also a possibility that confounding variables are not included in the analysis
that should have been. In our study such factors could have been assessment of mothers’
attachment patterns, the effect of psychological assessment and referral procedure and an
assessment of the comforting conditions for mother-infant interactions in the hospital.
However, our study results may still be of value for future research that will systematically
explore the complexity of factors influencing early preterm mother-infant interaction in a
broader sense.
The participants in this study were included consecutively and both single and multiple
births were included, thus minimizing selection bias. Our sample was homogeneous in socio-
economic background (SES). However, the mothers had higher educational attainments,
greater age and higher socioeconomic status, higher number of twins and higher rate of
previous psychological treatment than would be found in a typical population of mothers who
deliver preterm in our country. In this sample we found no indication of significant
differences in parental challenges between participants with singletons or twins that needed to
be controlled for. Besides high prevalence of earlier psychological treatment among the
mothers in our sample, no other collected data indicated that mental distress had impact on
their psychosocial function in everyday life before the actual preterm birth incident.
Regarding research on quality of the preterm mother-infant interaction, it has been considered
that risk factors other than preterm birth itself have been sources of bias in many studies.[20,
48, 96] In our study, we have controlled for high risk socio-economic backgrounds.
It is a limitation that the video-procedure of PCERA could not be followed for the four
dyads that were recorded in their homes and not in the clinic, as were the others. On the other
hand, these dyads would not have participated if the recordings were not made in their homes.
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It is a limitation that interrater reliability was not checked for tentative clinical diagnosis. The
prediction model used in this study needs further validation by future studies.
CONCLUSIONS
Our study detected a correspondence between early pregnancy complications and
lower quality of preterm mother-infant interaction, and an association between high levels of
maternal mental health problems and better quality in preterm mother-infant interaction.
Early intervention programs should be considered to mothers who give preterm birth to
support mother-infant interaction.
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Acknowledgements
The authors would like to thank the families that participated in the study, the staff of the
maternity ward at the neonatal intensive care unit at the National Hospital, Oslo and Sari
Ahlqvist-Björkroth who coded and Tanja Lipasti who recoded the PCERA data. In particular,
we want to thank the parents who participated in the study.
Contributorship statement
ARM initiated the study, collected, and organized the data. ARM and AHP performed the
statistical analyses. ARM, PN, SB, AHP and THD wrote the article.
Competing interests
We have no information of disclosure of interests.
Funding
This work was supported by the Centre for Child and Adolescent Mental Health, Eastern and
Southern Norway and the University College of Oslo and Akershus.
Data sharing statement
The full dataset is available from the corresponding author Aud R.
Misund([email protected]).
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87. Downey, G. and J.C. Coyne, Children of depressed parents: an integrative review. Psychological bulletin, 1990. 108(1): p. 50.
88. Goodman, S.H. and I.H. Gotlib, Risk for psychopathology in the children of depressed
mothers: a developmental model for understanding mechanisms of transmission. Psychological review, 1999. 106(3): p. 458.
89. Lovejoy, M.C., et al., Maternal depression and parenting behavior: A meta-analytic
review. Clinical Psychology Review, 2000. 20(5): p. 561-592. 90. Tedeschi, R.G., C.L. Park, and L.G. Calhoun, Posttraumatic growth: Conceptual
issues, in Posttraumatic growth: Positive changes in the afternath of crisis, R.G. Tedeschi, C.L. Park, and L.G. Calhoun, Editors. 1998, Earlbaum: Mahwah, NJ. p. 1-22.
91. Calhoun, L.G. and R.G. Tedeschi, The foundation of posttraumatic growth: An
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93. Bendersky, M. and M. Lewis, The Impact of Birth Order on Mother-Infant
Interactions in Preterm and Sick Infants. Journal of Developmental & Behavioral Pediatrics, 1986. 7(4): p. 242-246.
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94. Cohen, S.E. and L. Beckwith, Caregiving Behaviors and Early Cognitive
Development as Related to Ordinal Position in Preterm Infants. Child Development, 1977. 48(1): p. 152-157.
95. Kazdin, A.E., Research design in clinical psychology. 5th ed. 2013: Pearson New International Edition.
96. Wille, D.E., Relation of preterm birth with quality of infant--mother attachment at one
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STROBE 2007 (v4) Statement—Checklist of items that should be included in reports of cohort studies
Section/Topic Item
# Recommendation Reported on page #
Title and abstract 1 (a) Indicate the study’s design with a commonly used term in the title or the abstract 1
(b) Provide in the abstract an informative and balanced summary of what was done and what was found 1
Introduction
Background/rationale 2 Explain the scientific background and rationale for the investigation being reported 3-4
Objectives 3 State specific objectives, including any prespecified hypotheses 4
Methods
Study design 4 Present key elements of study design early in the paper 5
Setting 5 Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data
collection
5
Participants 6 (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up 5
(b) For matched studies, give matching criteria and number of exposed and unexposed
Variables 7 Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if
applicable
5-9
Data sources/
measurement
8* For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe
comparability of assessment methods if there is more than one group
5-9
Bias 9 Describe any efforts to address potential sources of bias 5 -9
Study size 10 Explain how the study size was arrived at 5
Quantitative variables 11 Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and
why
9-10
Statistical methods 12 (a) Describe all statistical methods, including those used to control for confounding 9-10
(b) Describe any methods used to examine subgroups and interactions 9-10
(c) Explain how missing data were addressed
(d) If applicable, explain how loss to follow-up was addressed
(e) Describe any sensitivity analyses
Results
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Participants 13* (a) Report numbers of individuals at each stage of study—eg numbers potentially eligible, examined for eligibility, confirmed
eligible, included in the study, completing follow-up, and analysed
5
(b) Give reasons for non-participation at each stage 5
(c) Consider use of a flow diagram 5
Descriptive data 14* (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential
confounders
5-7
(b) Indicate number of participants with missing data for each variable of interest
(c) Summarise follow-up time (eg, average and total amount) 5
Outcome data 15* Report numbers of outcome events or summary measures over time 5-9
Main results 16 (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, 95% confidence
interval). Make clear which confounders were adjusted for and why they were included
11-13
(b) Report category boundaries when continuous variables were categorized
(c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period
Other analyses 17 Report other analyses done—eg analyses of subgroups and interactions, and sensitivity analyses 11-13
Discussion
Key results 18 Summarise key results with reference to study objectives 14
Limitations
Interpretation 20 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from
similar studies, and other relevant evidence
2 and 16
Generalisability 21 Discuss the generalisability (external validity) of the study results 2
Other information
Funding 22 Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on
which the present article is based
18
*Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.
Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE
checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at
http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org.
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