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OB Exam 1Terms
Pregnancy
The implantation of a zygote into a woman’s body. Pregnancy occurs when a woman’s body responds to the hormonal signals that indicate fertilization has occurred. The ovum is fertilized.
Prenatal
Before birth
Postnatal
After birth
Perinatal
A 48-hour time period including the day before and the day after birth
Neonatal
The time period including the first 4 weeks of life
Premature
A fetus born at less than 36 weeks gestational age
Postmature
A fetus born at greater than 42 weeks gestational age
Gravida
The number of pregnancies including the current one
Para
The number of pregnancies carried to term
Nullipara (Nullip)
Characterizes a woman during her first pregnancy
Multipara (Multip)
Characterizes a woman after several pregnancies
Grand Multip
Characterizes a woman who has 5 or more successful previous
pregnancies
Trimester
The 40 weeks from LNMP of a normal pregnancy is divided into 3 trimesters of 13
week duration.
Pregnancy is 266 days +/- 10
When patient conceives 14 days after the first day of the LNMP the pregnancy is 280 days or 40 weeks from the first day of the LNMP
LNMP
Last normal menstrual period; First day of cycle or LMP
Pregnancy dating
In US, dated from the 1st day of the LNMP
The earlier in pregnancy the sonogram is performed the more accurate the
dating
FISH
(fluorescence in situ hybridization)
Useful for gene-mapping and identifying chromosomal
abnormalities like Trisomy-21 or DiGeorge syndrome
Nabothian cyst
A mucus filled lump on the surface of the cervix caused by plugged up
mucus glands
Ovarian hyperstimulation
A syndrome usually seen in women who take certain fertility medicines
that stimulate egg production
Occurs after ovulation and ovaries become very swollen
Demise
The loss of a fetus at any stage
Chorionic villus sampling
The removal of a small piece of placenta tissue (chorionic villi) from the uterus during early pregnancy to screen the baby for genetic defects
Percutaneous umbilical blood sampling (PUBS)
A highly specialized prenatal test in which a blood sample is removed
from the umbilical cord and tested for genetic problems or infections
PUBS can be done after the 18th week of pregnancy
Methotrexate
One of the most effective and commonly used medicines in the treatment of several
forms of arthritis and other rheumatic conditions
Known as a disease-modifying anti-rheumatic drug because it not only
decreases the pain and swelling of arthritis, but it also can decrease damage to joints
and long-term disability
Propaganda
Ideas, facts, or allegations spread deliberately to further one’s cause or to damage an opposing cause; also; a
public action having such an effect
Thoracoamniotic shunting
The treatment of choice for management of the fetus with
symptomatic fetal hydrothorax (FHT) before 32 weeks of gestation
Intrauterine growth restriction
(IUGR)
Reduced growth rate (symmetrical IUGR) or abnormal growth pattern (asymmetrical IUGR) of the fetus; resulting in a small for gestational
age (SAG) infant
Human chorionic gonadotropin
(hCG)
Hormone secreted by syncytiotrophoblasts of the developing
embryo
Laboratory test indicates pregnancy when values are elevated
hCG levels will likely decrease after the 1st trimester when the placenta takes
over
Macrosomia
Exceptionally large infant with excessive fat deposition in the
subcutaneous tisse
Most frequently seen in the fetuses of diabetic mothers
Maternal serum alpha-fetoprotein (MSAFP)
Biomedical test used to assess fetal risk for aneuploidy or fetal defect (neural tube
defects)
Component of the “triple screen”
Normal value varies with gestational age
Maternal serum is tested between 15-22 weeks of gestation to detect abnormal levels
Polycystic Ovarian Syndrome
Ovary doesn’t make all the hormones it needs for the egg to fully mature, so the
follicle grows and builds up fluid
Most common cause of female infertility
Decidua
Endometrium of pregnancy“falling away”
Decidua basilis
The decidua in contact with the chorion frondosum, which eventually develops
into the placenta
Chorion frondosum
Villous chorion
Decidua capsularis
The decidua in contact with the chorion laeve
When the decidua capsularis is pressed against decidua vera on the opposite side
of the endometrial cavity by the developing pregnancy, the villi attach to the chorion
laeve regresses or may slough off
Chorion laeve
Smooth chorion
Decidua parietalis(decidua vera)
Endometrial lining which is not initially involved in the implantation and is therefore not associated with the
placenta
Chorion
Extraembryonic membrane that is formed from trophoblastic cells and forms the outer
wall of the blastocyst at the time of implantation
Outer membrane adjacent to the uterine wall, then extending over the fetal side of
the placenta
Chorionic frondosum
(villous chorion) Interweaving of chorion villi and decidua basalis.
Establishes early utero-placenta circulation
Amnion
The inner membrane which holds the embryo suspended in the amniotic fluid
Amnion extends over the placenta except at the umbilical cord where it is continuous with the outer membrane of the cord
@6 weeks amnion is closely adjacent to the embryo
@8 weeks is more circular in shape
By 10 weeks occupies most of gestational sac
By 15th week it is fused with the chorion
Syncytiotrophoblast
Cells form isolated spaces called lacunae which later develop into intervillous
spaces in the placenta where maternal blood flows and makes contact with fine
fetal capillaries in the villi, finger like projections of placental tissue
Placenta
Organ that provides hormones to support pregnancy and that is the site of communication between the mother’s
blood and fetal capillaries contained within the villi
Threatened abortion
Bleeding in early pregnancy
Inevitable abortion
Term assigned after it is determined that the pregnancy is non-viable
Elective abortion
Medical term for an induced abortion performed at a woman’s request
Missed abortion
Occurs when the products of gestation remain in the uterus and cause
continued bleeding
Therapeutic abortion
An induced abortion for the health of the mother
Pre-eclampsia
Having high blood pressure during pregnancy and too much protein in
urine at 20 weeks
Choriocarcinoma
Type of gestational malignant tumor that arises from the trophoblasts of the forming placenta within the uterus
Theca Lutein Cyst
Nonfunctional cyst found on the ovary and are associated with excess amounts
of gonadotropins
Cervical cerclage
Surgical procedure to correct cervical incompetence
Cervix is stitched closed so that premature birth or miscarriage is
avoided
Decidual cast
Occurs when the decidua of the uterus discards
Appearance of the uterus when it comes out
Well known with ectopic pregnancies
Adnexa
Parts next to each other or attached to each other
Mullerian duct
Ducts in the embryo that develop into female parts
Idiopathic
Spontaneous or unknown cause or origin
Braxton hicks
False labor pains that often occur early on in pregnancy
Not a true contraction
Hyperemesis gravidarum
Excessive vomiting during early pregnancy that results in at least a 5%
reduction in body weight
Blighted ovum
A miscarriage in which the baby does not develop or demises early but the
gestational sac remains
PAPP-A
Pregnancy Associated Plasma Protein A
Can be a part of 1st trimester screening measure with a blood test
D & C
Dilation and curettage
A procedure in which the cervix is dilated in order to remove the
endometrium
MSD
Mean sac diameter
Figured from several different measurements
Fundal height
Abdominal measurement of the uterine length
Measured from the symphysis pubis to the tip of the fundus in cm
The cm length approximates the weeks of gestation
Large for gestation age
A baby whose weight is greater than 4000 grams at term
Small for gestational age
A full term baby whose weight is less than 2500 grams at birth
Hi-risk pregnancy
A pregnancy with maternal or fetal factors which predispose to increase
maternal or fetal morbidity and mortality
• Bleeding• Polyhydramnios• Development of hypertension
Normal fetal heart rate
120 – 160 bpm with marked variability
Reactive fetal heart rate
Heart rate increases with movement
Aka: fetal heart acceleration
Estriol
Estrogen product produced by the placenta from fetal precursors
estradiol
Estrogen product produced by the placenta from maternal precursors
Triple screen
A measurement of estriol, HCg, and AFP in the maternal serum
Fetal monitoring
Monitoring of fetal heart rate and uterine contractions
Placental reserve(placental suficiency)
Measurement of the ability to supply sufficient oxygen to the fetus even during
contractions, which reduce maternal blood supply to the placenta
*If placental reserve is not adequate, it is said that the patient has placental insufficiency
Cervical effacement
Shortening of the cervix
Cervical dilation
Dilation (opening) of the cervix
Quickening
Initial perception of fetal movement by the mother
Usually occurs between 17 and 21 weeks
*inexact method of determining EDC
Timing related to:• Parity• Position of the placenta• Awareness of mother
Oligohydramnios
Insufficient amounts of amniotic fluid
Polyhydramnios
Excessive amounts of amniotic fluid
Apgar score
Standard for comparing the condition of the baby at birth and a way of detecting depressed
newborns
Measurements of 0,1,2 are given for:• Heart rate• Respiratory effort• Muscle tone• Reflex irritability• Color
**Apgars are noted at 1 & 5 mins after birth**healthy baby will have an apgar of 8-10
Biophysical fetal profile
An intrauterine score designed to detect depressed fetuses
Scores of 0 or 2 are given for:• Fetal breathing movements• Gross body movement• Fetal body tone• Reactive fetal heart rate• Amniotic fluid volume
Dubowitz score
Standard test of the baby’s physical characteristics and neurological (reflex)
responses that is completed in the nursery during the first 24 hours of life
Primordia
The first recognizable, histologically differentiated stage in the development
of an organ
Allantois
A vascular fetal membrane of reptiles, birds, or mammals that is formed as a
pouch from the hindgut and that in placental mammals is intimately
associated with the chorion in formation of the placenta
BhCG
Produced by the cells of the implanting egg and can be produced in the absence
of an embryo
Can be detected in maternal plasma or urine by 8 – 9 days after ovulation
Trisomy-13
A syndrome associated with the presence of an extra chomosome 13
Characterized by mental retardation, cardiac problems, and multiple
deformities
Verix or vernix caseosa
A white substance covering the skin of a baby directly after birth
Composed of sebum and cells that have sloughed off fetus’ skin
Pyelectasis or hydronephrosis
Dilation of the renal pelvis in a fetus due to urine or fluid collection
• Hydronephrosis – when it exceeds 10mm at 20-24 weeks
• Pyelectasis – when greater than 4mm and less than 10mm in a fetus under
24 weeks
Transudation
A fluid or solute moving through a membrane
It moves by osmotic or hydrostatic pressure gradient
Wharton’s jelly
A supportive tissue derived from extraembryonic mesoblast that
surrounds the umbilical cord protecting the vessels within
Without it may be easier to compress the vessels and even cause fetal death
Congenital anomaly
Something that is unusual or different at birth
Minor anomaly
Defined as an unusual anatomic feature that is of no serious medical or cosmetic
consequence to the patient
Major anomaly
By contrast to minor anomaly might be a cleft lip and palate, a birth defect of
serious medical and cosmetic consequence to the child
Hydrocele
A fluid-filled sac surrounding a testicle that results in swelling of the scrotum
Up to 10% of male infants have a hydrocele at birth, but most disappear without treatment within the first year
of life
Cerebellar vermis
Portion of the cerebellum in the midline is not as prominent as the lateral
hemispheres
Receives visual input from the superior colliculus and is involved in coordinating
eye movements and speech
Cotyledon
Discrete elevations of chorioallantoic tissue of the ruminant fetal membranes that adhere intimately with the materal
caruncles to form placentomes
Aneuploidy
Refers to the abnormal copy number of genomic elements
One of the most common causes in morbidity and mortality in human
populations
OB Exam 1
Normal First Trimester
How many chromosomes are in a gamete
Haploid - 23
How many chromosomes after fertilization?
Diploid - 46
What do the follicles on an ovary produce?
estrogen
What does estrogen stimulate?
The endometrium to grow and thicken
What releases gonadotropin?
Hypothalamus
What stimulates the pituitary to release luteinizing hormone and FSH?
Gonadotropin
What does the luteinizing hormone stimulate?
For one follicle to mature
Where does the oocyte go after it is released?
Fallopian tube
What happens to the follicle after rupture?
Becomes corpus luteum & produces progesterone
What causes menstruation?
If fertilization doesn’t occur, estrogen & progesterone drop
Where does fertilization typically occur?
Fallopian tube
What happens to the corpus luteum after fertilization?
Continues to produce progesterone and some estrogen
What stage are weeks 1 – 4?
Zygote
What stage are weeks 5 – 10?
Embryo
What stage are weeks 11 – 40 ?
Fetal stage
When and how is a morula formed?
By day 3 – 4, from the fertilized ovum (zygote) divides
What is the organized form of the morula?
Blastocyst
What feeds the blastocyst?
The thickened endometrial layer (decidua)
What are the outer cells of the blastocyst?
Trophoblast
What part of the blastocyst becomes the embryo?
The cell disc
What are the 2 layers of the trophoblast?
1. Inner – cytotrophoblast2. Outer layer - syncytiotrophoblast
What does the cytotrophoblast form?
• Chorion• Amnion
• Connecting stalk
What does the syncytiotrophoblast do?
• Invade the decidua• Form lacunae (which develop into
intervillous spaces)
What hormone does the trophoblast secrete?
hCG
What is the purpose of hCG?
Extends the life of the corpus luteum/progesterone
When does the blastocyst implant?
7 days after fertilization
What happens to the primary yolk sac?
It disappears
What connects the secondary yolk sac to the fetal body?
Vitelline duct (yolk stalk)
Where is the secondary yolk sac?
In the extraembryonic coelum, between the amnion and chorion
What is normal size for the secondary yolk sac?
< 6mm
What is the function of the secondary yolk sac?
Nutrients and hematopoiesis
What days in the zygote stage does conception happen?
14 days
When does the morula become a blastocyst?
18 – 21 days
When does implantation begin?
19 – 21 days
What happens in days 25 – 26 of the zygote stage?
• Implantation complete• Lacunar network formed• Focal thickening of the decidua at
the site of implantation
What happens in response to estrogen and progesterone?
Transformation of endometrial cells into glycogen and lipoid cells
What are the 3 distinct layers of the decidua?
• Decidua basalis• Decidua capsularis• Decidua parietalis (decidua vera)
Which decidua attaches at the chorion frondosum
Decidua basalis
Which decidua is not involved in implantation?
Decidua parietalis (decidua vera)
Which decidua develops into the placenta?
Decidua basalis
Which decidua covers the remaining endometrial cavity?
Decidua parietalis (decidua vera)
Which decidua closes over the blastocyst?
Decidua capsularis
When can the Intradecidual Sac Sign / Double decidua sign be seen?
Week 4
What stage are weeks 5 – 10?
Formation stage
What structures are present in weeks 4 – 5?
• Yolk sac• Neural plate and folds
What are the sonographic features of week 4 – 5?
• Yolk sac in the gestational sac• Located in the fundus• Round or oval with smooth walls• Decidual thickening of >3mm
Where would the yolk sac been seen in week 4 – 5?
Between the amnion and chorion
By what day should the gestational sac be seen?
Day 34 (4 weeks)
By what day should the yolk sac be seen?
Day 42 (5 weeks)
In week 4 – 5, what should the diameter of the gestational sac be?
8 mm
In weeks 4 -5 what should the hCG count be?
1800 mlU/ml
In weeks 4 – 5, what should the decidual wall thickening measure?
> 3 mm
What structures are present in weeks 5 – 6?
• Limb buds• Primordia of liver, pancreas, lungs, thyroid
gland, heart• Neural groove closes and the primary brain
vesicles form• Opitcal vesicles • 2 heart tubes fuse and contraction begins
with unidirectional blood flow
What are the sonographic features of week 5 – 6?
• Double blep sign (amnion with yolk sac• Embryo may be seen adjacent to yolk
sac• Embryo heart beat• Double decidua sign
What week should the embryo be seen?
Or size of the gestational sac?
By week 6, or gestational sac of 1.5 cm
What would the embryo measure to be able to detect heart beat?
5 mm CRL7mm CRL (2014 Notes)
What structures are seen in week 6 – 7?
• Brain has single vesicle• Heart bulges from the body• Embryo is C-shaped• Arm buds elongate, leg buds appear• Nostrils and eyes develop
What are the sonographic features of week 6 -7?
The amnion is close to the embryo
What is the CRL in week 6 -7?
9 – 10 mm
What happens in week 7 – 8 ?
• Body axis straightens• Arms & legs extend straight forward• Digits, ears, eyelids, elbow, and wrists are
formed• Pulmonary trunk separates from heart• renal pelvis, calyces, and ureters form• Brain has 3 vesicles
What would the CRL be in week 7 – 8?
21 – 23 mm
What happens in week 8 – 9?
• More straightening of axis• Touch pads swollen on fingers• Midgut herniates into the umbilical
cord (between weeks 8 – 12)• Brain hemispheres and falx formed
What are the sonographic features in week 8 – 9?
The choroid plexus is seen in the lateral ventricles
What would the CRL be in week 8 – 9?
28 – 30 mm
What happens in week 9 – 10?
• Eyelids cover eyes• Brain structures complete• Rapid growth
What would the CRL be in week 9 – 10?
30 – 40 mm
What would the CRL be week 11 & up?
40 – 85 mm
By when should the kidneys be seen in adult position?
15 weeksBy 14 weeks (2014)
By when should the stomach be seen?
12 weeks
When does the midgut herniation return to the abdominal cavity?
11- 12 weeks
When is the cerebellum formed?
11 Weeks
When does ossification of long bones begin?
12 weeks
When should cranial anatomy be seen?
After 12 weeks
When should the bladder be seen?
By 14 weeks
When should the 4 chamber heart be seen?
At 12 weeks
What does the mean sac diameter correlate with?
Menstrual age(1 cm = 1 week)
((Accurate through Wk 8)
What diameter should the yolk sac never exceed?
6 mm
What is the most accurate way to date a pregnancy?
By the crown rump length
With what accuracy does the CRL date the pregnancy?
+ / - 5 days((To 13 Wks Gestation))
What is included in the mean sac diameter?
Only anechoic fluid space, not walls
Where should the gestational sac be located?
To one side of the endometrium near fundus
When should the yolk sac be seen?
When the mean sac diameter is 8 mm
When should the fetal heart rate be visualized?
By 6 weeks(via TV)
What is the normal fetal heart rate?
90 – 175 bpm
When is the nuchal Translucency seen?
In the first trimester
When do you measure NT?
• 10 to 14 weeks
What is the nuchal lucency?
Anechoic area in the posterior nuchal region of the fetus
What does nuchal translucency screening detect?
What is a normal NT?
< 3.4 mm
The risk for having a child with trisomy 21, 13 and 18
What factors are include in nuchal transluceny screening?
• PAPP-A values• BhCG lab values• Maternal age• Fetal nuchal translucency
measurement
What forms the umbilical cord?
The fusion of the yolk stalk and allantoic duct
When does the umbilical cord develop?
During the 7 – 8th week
What forms the umbilical vessels?
The allantois vessels
What is the cavity between the amnion and chorion?
Extraembryonic coelum(chorionic cavity)
What is the inner membrane that suspends the embryo in amniotic fluid?
Amniotic membrane – Covers the cord as it expands
What is the outer membrane that implants to form the placenta?
Chorion membrane
When does the amnion and chorion fuse?
By 16 weeks
When is quantitative hCG assessed?
1st and 2nd trimester
Where is beta hCG produced?
By trophoblasts
When should the 2nd international standard be positive?
(Pregnancy Test)
7 – 10 days after conception
What could be the cause for increased serum levels?
• Incorrect dates• Multiple gestations• Trophoblast dissease (greater than 60,000
mIU/ml early
What could be the cause of decreased serum levels?
• Incorrect dates• Embryonic demise• Ectopic pregnancy – will show
slow rise but overall value is decreased
Where is PAPP-A glycoprotein produced?
by trophoblasts
What does a decrease in PAPP-A indicate?
Aneuploidy (Downs)
OB EXAM #1
1st Trimester Pathology
What is the incidence of bleeding in pregnancy after the LNMP?
20 – 25 %
What is the continuation rate for light bleeding?
84 %
What is the continuation rate for moderate bleeding?
40 %
What is the continuation rate for heavy bleeding?
20 %
What are the non-pregnancy causes of bleeding?
• Cervical polyps• Cervical infection
What is a complication of hyperemesis gravidarum?
Dehydration
Hyperemesis gravidarum may be related to__________.
Elevated B-hCG
B-hCG are highest when?
• Molar pregnancies• Higher in twins than singletons
What are common causes of pain in pregnancy?
• Movement of retroverted uterus to an anteverted position
• Torsion of corpus luteum cyst or theca lutein cyst (with molar pregnancy or hyperstimulation
• Cramping with bleeding may signify cervical dilation or venous congestion
• Should pain or leg pain associated with ectopic pregnancies
What does the development of hypertension in the first trimester related to?
Poor function or the presence of a molar pregnancy
What does development of hypertension later in pregnancy relate to?
One symptom in the triad signaling development of pre-eclampsia
What are the etiologies of pregnancy failure/disruption in 1st trimester?
• Idiopathic• Endocrine factors• Corpus luteum failure• Mullerian duct anomalies• Embryonic failure• Chromosomal anomalies
What is TAB?
Therapeutic abortion
What is SAB?
Spontaneous abortion
What percentage of pregnancies end in SAB?
12 %
75 % end in SAB before what week?
Week 16
What are the categories of SAB?
• Complete abortion• Incomplete abortion• Missed abortion• Inevitable abortion• Blighted ovum• Threatened abortion • Imminent abortion
What is complete abortion?
Evacuation of all products of conception
What are the signs/symptoms of a complete abortion?
• Rapid decline in hCG• Heavy vaginal bleeding with tissue/clots• Cramping • Cessation of pain and bleeding after
event• Disappearance of signs of pregnancy
What are the sonographic features of a complete abortion?
• An empty uterus with a clean endometrial stripe
• No adnexal mass or free fluid• Moderate to bright endometrial
echoes (may be thickened)
Incomplete abortion is also known as _______
Retained products of conception
What are the signs/symptoms of an incomplete abortion?
• Slow fall or plateau of hCG• Moderate cramping• Persistent moderate to heavy
bleeding
What are the sonographic features of an incomplete abortion?
• Complex echo pattern within endometrial cavity
• Bright echoes, may shadow to air bubble or bone fragments
• Thickened endometrium
What is a missed abortion?
An intact nonliving embryo
What are the signs/symptoms of a missed abortion?
• hCG levels less than expected • Loss of pregnancy symptoms• Brownish vaginal discharge• Some cramping/pain
What are the sonographic features of a missed abortion?
• Absent cardiac and limb activity• Fetal size is less than expected• Uterine size is less than expected
What is an inevitable abortion also called?
Pending abortion
What are the signs/symptoms of an inevitable abortion?
• Uterus is small for dates• Variable/low hCG levels• Vaginal spotting• Cervical dilation
What are the sonographic features of an inevitable abortion?
• Gestational sac is not in the fundus and closer to the cervix
• Rupture of membrane with no chance of survival
What are the sign/symptoms of an imminent SAB?
• Moderate cervical effacement• Rupture of membranes/leaking
fluid• Prolonged bleeding• Persistent cramping
What are the sonographic features of an imminent SAB?
• Heart rate is less than 90• Persistent misshapen yolk sac• Gestation sac in the cervix or
lower uterine segment• Cervical dilation• Small gestational sac
What is thought to be the cause of a blighted ovum?
Early demise
What is a blighted ovum?
Anembryonic pregnancy/empty sac. The gestational sac in utero without
embryo or yolk sac, with irregular borders
What are the sign/symptoms of a blighted ovum?
• Uterus is small for dates• Variable hCG levels• Vaginal spotting• Closed cervix
What are the sonographic features of a blighted ovum?
• No identifiable embryo in a gestational sac that is bigger than 25 mm
• Absent double blep sign
What is a threatened abortion?
The future of pregnancy at risk but is currently viable
Not able to diagnose sonographically
What are the signs/symptoms of a threatened abortion?
• Closed cervix• Slight bleeding or cramping
Some bleeding in pregnancy is common from ___________
Implantation bleeding
What is the chance of loss in pregnancy under 7 weeks after the heartbeat has been seen?
24 %
What is the chance of loss in pregnancy over 7 weeks after the heartbeat has been seen?
3 %
What are the sonographic features of a threatened abortion?
• Sonolucent crescent around GS
What could the sonolucent crescent around the GS be?
Subchorionic hemmhorage or unknown bleeding
What is habitual abortion?
3 or more miscarriages
What are the causes of habitual abortions?
• Often genetic incompatibility• Fibroids• Uterine anomalies• Adenomyosis• Incompetent cervix
What is the incidence of all pregnancies for an ectopic pregnancy?
2%
What percentage of ectopic pregnancies are in the fallopian tube?
95 %
Where do ectopic pregnancies occur?
• Peritoneum• Ovarian • Cervical • Interstitial/cornual• Intermural• Heterotopic
What is the occurrence of maternal deaths with an ectopic pregnancy?
10 %
What are the risk factors for ectopic pregnancies?
• Damage to Fallopian tubes• Previous PID or ectopic• Tubal surgeries• Endometriosis
• Use of IUD• Infertility treatment
What are the signs/symptoms of an ectopic pregnancy?
• Pain• Vaginal bleeding (35 %)• Palpable adnexal mass• Asymptomatic• Shock if ruptured• hCG doesn’t rise as it should
What is the occurrence of a live extrauterine pregnancy in the adnexa?
25 %
Where is an ectopic most commonly found?
The same side with the corpus luteum
(has the appearance of a cyst)
What are features of a pseudogestational sac?
• No embryo or yolk sac• Centrally located• Homogeneous echoes within• High resistant waveform
What is the trend in hCG with ectopic pregnancies?
To increase at slower rates than normal
If no IUP is seen and hCG is greater than 1000 IU/ml, what does this typically indicate?
Ectopic pregnancy or very recent miscarriage
What is the pre-symptomatic phase of ectopic pregnancy?
May be picked up by low hCG level, lack of IUP on sonogram
What is the symptomatic phase of ectopic pregnancy?
• Tubal rupture, intraperitoneal bleeding
• Shock, hypotension, abdominal pain
What is the 2nd most common type of ectopic pregnancy?
Interstitial/cornual ectopic
What are the features of an interstitial/cornual ectopic pregnancy?
• Eccentric sac location in uterus• Less than 5 mm distance from sac
to uterine serosa• May be live or may just be a mass
What kind of ectopic pregnancy has the highest maternal mortality rate?
Interstitial/corual ectopic
Why does cornual ectopic have the highest maternal mortality rate?
Massive hemmorhage
What would a sac in the cervix be?
Cervical ectopic
What is the potential with a cervical ectopic?
Massive hemorrhage & Future Infertility
Which ectopic is difficult to diagnose?
Peritoneal ectopic
To diagnose a peritoneal ectopic, what must be seen?
The uterus separate from pregnancy
What may mimic an ovarian mass?
Ovarian ectopic
What type of ectopic is the history important?
Ovarian ectopic
What is a coexisting IUP and ectopic?
Heterotropic ectopic/pregnancy
Why are heterotopic ectopic/pregnancy increasing?
Infertility procedure
What is the treatment for ectopic pregnancies?
• Oral low does methotrexate, which kills trophoblastic tissue
• Injection of methotrexate directly into sac
• Laparoscopy to remove portion affected
What is the cause of the most common bleeding in the 1st trimester?
Subchorionic hemorrhage
What causes subchorionic hemorrhage?
Implantation of blastocyst
What is subchorionic hemorrhage?
Low pressure bleeding between the gestational sac and placenta
What are the signs/symptoms of subchorionic hemorrhage?
• Bleeding & spotting• Uterine contractions
What are the sonographic features of subchorionic hemorrhage?
• Crescent shaped• Echogenic area (recent)• Anechoic (old)• No color Doppler
What is a Hydatidiform Mole?
Produce of conception in which trophoblast cells fail to differentiate so produces abnormal
placental tissueMore common in Asians
What are hydatidiform moles associated with?
Theca Lutein CystsOver$ due to high hCGLargest functional cyst
Bilateral 6-12 cmMultiple & septations common
Signs and Symptoms of Hydatidform Mole
• Increased hCG (Hyperemesis)• Bleeding• HTN/Preeclampsia• Decrease AFP• Uterus Enlarged• Theca Lutein Cysts (Bilateral)
What is seen more in the 2nd trimester, and is a higher pressure bleed?
Placental hematoma
What is the cause of placental hematoma?
Placental separation
What relates to the outcome of the pregnancy with placental hematomas?
How large it is
What is the appearance of a placental hematoma?
Similar to subchorionic hemorrhage
What is the incidence of fetal demise with placental hematoma?
50 %
When is an incompetent cervix most common?
2nd trimester
What are the characteristics of an incompetent cervix?
• Shortening, and opening so that membranes may protrude
• Painless dilation and delivery
What length is considered shortened in a cervix?
Less than 3.0 cm length
What are the sonographic features of an incompetent cervix?
• Funneling of Y, V, U shape
What is the treatment(s) of an incompetent cervix?
Cervical cerclage
What are the masses that coexist with pregnancy that are seen?
• Corpus luteum cyst• Leiomyomas • Myometrial contractions (mimics a mass)• Hematosalpinx/hematoma• IUCDs with coexisting IUP• Uterine anomalies
A corpus luteum cyst is most common in _____________, and usually regresses by
_____________
1st trimester2nd trimester
If a corpus luteum cyst continues after then 1st trimester, what is then considered?
Surgical removal
What type of uterine mass may increase in size in 1st trimester and early 2nd trimester?
Leiomyomas
What causes leiomyomas to increase in size in the 1st and 2nd trimesters?
Estrogen
What is a concern with leiomyomas and pregnancy?
Can compress the sac if it grows too fast
What are the features of a leiomyoma?
• Attenuates sound• Hyper to hypoechoic• Differentiate from Braxton-Hicks
contractions by:• Decreased vascular in fibroid• Doesn’t disappear over time
When are myometrial contractions most common?
1st and 2nd trimesters
What are the features of a myometrial contraction?
• Painless contraction • Myometrium thickens for 20 – 30 mins• Spontaneously disappears
What causes hematosalpinx/hematoma?
Implantation bleeding or other GYN infection
What is a hydatidiform Mole?
• Gestational trophoblastic disease
The product of conception in which the trophoblast cells fail to differentiate so they produce abnormal placental tissue
To whom are hydatidiform moles most common?
Asian descent
What are hydatidiform moles associated with?
Theca lutein cysts
• Largest functional cyst• Seen 20 – 35 % of the time• Overstimulation due to high hCG levels• Bilateral• Multiple and septations common
What are the sign/symptoms of a hydatidiform mole?
• Bleeding• Increased hCG• Hyperemesis• Preeclampsia• Decreased AFP• Uterus is large for gestational age• Theca lutein cysts (bilateral)
Is a complete mole benign or malignant?
Benign form, with malignant potential
What is the cause of a complete mole?
An abnormal ovum, or 2 sperm fertilizing an ovum
What is the incidence of a partial (incomplete) mole of all moles?
5 %
Is a partial mole considered benign or malignant?
Benign, has very little malignant potential
What is the appearance of the placenta with a partial mole?
Enlarged and engorged with cystic spaces
What is a partial mole?
Hyperplasia of trophoblast will be localized within placenta rather than
general
What is the ploidy of a complete mole?
Normal diploid
What is the ploidy of an incomplete mole?
Triploid
Can a fetus coexist with a complete mole or incomplete mole?
Incomplete mole
What is an invasive mole?
Hydropic villi invades myometrium
What percentage of molar pregnancies move to an invasive mole?
15 %
What are the sign/symptoms of an invasive mole?
• Persistent bleeding• Elevated hCG
What is choriocarcinoma?
Malignant metastatic trophoblastic disease
What is the incidence of molar pregnancies progressing to choriocarcinoma?
2 – 5 %
What are the characteristics/appearance of
choriocarcinoma?
• Spreads quickly• Complex in appearance
throughout myometrium
What is the sonographic appearance of choriocarcinoma in the 1st trimester?
• May appear normal• Appear like a missed abortion• Incomplete abortion/blightled ovum• Echogenic mass in endometrium
• Cyst may be too small
What is the sonographic appearance of choriocarcinoma in the 2nd trimester?
• Snowstorm / grape clusters• mid level tissue with cysts
(chorionic villi)
What is the treatment for choriocarcinoma?
Curettage
What is the residual rate of choriocarcinoma after evacuation?
20 %
What is the most common abnormality of the first trimester in the fetus?
Cystic hygroma
What is cystic hygroma likely associated with?
Chromosomal abnormalities• Trisomy 21, 18, 13 and Turner’s
syndrome (most common)
What is the sonographic features of cystic hygroma?
• Vary in size• Soft tissue thickening on posterior neck
and thorax• **must differentiate from NT
What are the abnormalities found in the 1st trimester fetus?
• Cystic hygroma• Umbilical cord cyst• Obstructive uropathy• Abdominal wall defects• Cranial anomalies
What is methotrexate used for?
To terminate early pregnancy(most common for ectopic
pregnancy)
How effective is methotrexate injected if 6 weeks or less and the intact embryo is seen?
96 %
What are complications of methotrexate being injected?
Excessive bleeding
What is dilation and curettage (D&C) or dilation and evacuation (D&E)?
Method where the cervix is manually dilated and the endometrium is
scraped away
When is in vitro fertilization considered?
After 1 year with no conception
What is the sonographic usage for in vitro fertilization?
• Assess infertility cause• Ovary monitoring during stimulation• Egg retrieval assistance• Assess embryo after implantation
What are complications of in vitro fertilization?
• Multiple gestations• Fetal reduction• Hyperstimulation syndrome
Why is fetal reduction used?
To improve the survival rate of remaining fetus
Used with quadruplets or more to increase birth rate
When is fetal reduction used?
In late 1st trimester
What techniques are used in fetal reduction?
• Transcervical aspiration of GS• Infection possibility• Increases cervical incompetence
• Transvaginal puncture and embryo aspiration• Use of general anesthesia• Possible abortion• Infection possibility
• Tranabdominal injection of potassium chloride• Increased pregnancy loss when performed later in pregnancy
OB Exam 1
2nd Trimester Routine Sonogram
What percentage of fetuses are in the cephalic position at term?
95 %
What percentage of fetuses are in the breech position at term?
5 %
What is the occurrence of fetuses in the shoulder/transverse position at term?
rare
What structures are included in the facial profile?
Fetal foreheadFetal nose
Upper and lower lipsChin
What proportion is expected in the facial profile?
1/3 forehead1/3 eyes and nose
1/3 mouth and chin
What structures are present in the coronal face?
OrbitsEthmoid bonesZygomatic bone
Nasal septumMaxillae
Mandible
What structures are imaged in tangential views?
NostrilsMaxillaeMandible
Ears
Why do we document nose and lips?
To look for continuity of the upper lip (assessing for cleft)
What is assessed in the orbits?
That there are 2 present, and their spacing
How is the inner orbital distance measured?
Medial to medial border
How is the outer orbital distance measured?
Lateral to lateral border
What does the OOD (outer orbital distance) measurement compare to?
Better or as good as BPD
When does the appearance of the brain remain constant?
16 – 18 weeks
What is the appearance of the fetal brain by sonogram?
Hypoechoi – anechoic(small reflectors and water content high)
What kind of artifact is expected while imaging the fetal brain?
• In the near field ½ of brain• Reverberation or shadowing
When do the bones in the skull ossify?
By 12 weeks
What is the shape of the skull more superior (high)?
Round
What is the shape of the skull inferior (low)?
Oval
What is the ventricle pathway?
• Lateral ventricles• Foramen of Monro/interventricular foramen• 3rd ventricle• Aqueduct of Sylvius/cerebral aquaduct• 4th ventricle• Foramen of Maendie/Median Aperature• Subarachnoid space• Venous system
What is the appearance of the brain at the falx cerebri?
Thin midline hyperechoic line
What is the appearance of the brain just inferior to the falx cerebri?
White matter tracts parallel to falx
At the level of the lateral ventricles what other structure is seen?
Choroid plexus
What are the characteristics of the choroid plexus?
• Echogenic tear shaped• Near the posterior end of ventricles• The atria measure < 10 mm
What is the largest width of the cranium?
Mid diameter
What structures are present in mid diameter?
• Midline falx• Cavum septum pellucidum• Thalmus• 3rd ventricle
What is the shape of the head at mid diameter?
Oval and symmetric
What level is the BPD taken?
Mid diameter
How is the BPD measurement taken?
• Leading edge to leading edge of bone• No skin or tissue included
When is the BPD most accurate for growth and dates?
In the 2nd trimester
After 13 weeks
What level is the head circumference taken?
Mid diameter
Same as the BPD
How is the head circumference taken?
Outer margin of the skill, not including any tissue
What is another optional measurement that can be taken at the mid diameter?
Occipital frontal diameter
What is being assessed at the corpus callosum?
It’s presence
Not documented unless pathology is seen
Where is the cerebellum?
Within the posterior fossa
What are the hemispheres joined by?
Cerebellar vermis
Where is the cerebellar width measurement taken?
At the level of the cerebellum, vermis, and 4th ventricle
When is the cerebellum width measurement valid?
To 20 weeks GA
How does the cerebellar width measurement coincide with the GA?
Width in mm = GA in weeks
What is the normal measurement of the cisterna magna?
3 – 11 mm
Where is the cisterna magna measurement taken?
From vermis to inner skull bone
What is the appearance of the cisterna magna?
Anechoic with linear echoes of dura
What is the normal measurement of the nuchal fold?
5 mm or less
When do you measure the nuchal fold?
Between 15 – 21 weeks
What is the apperance of the sphenoid bone by sonogram?
An X
How should the vertebral column be imaged?
Coronally image the cervical, thoracic, and lumbar/sacral spine – to the tip of
the sacrum
What is being looked for when assessing the vertebral column?
• 2 -3 ossification points• Tapers at sacrum• Widens near skull base• 3 spread equidistance• Spinal column is closed circle• Integrity of skin surface
How will an abnormal vertebral column appear?
Splayed in a V or U configuration
What structures are assessed in the thorax?
• Ribs/bones• Lungs• Heart• Diaphragm
What is to be imaged for the ribs/bones?
Only documented when confenital anomalies suspected
How will the lungs appear?
Solid and homogeneousSlightly hyperechoic to liver
How should the heart be imaged?
Using zoom
What should be imaged in the heart?
• 4 chamber view • With septum perpendicular to beam
• Outflow tract• RVOT, LVOT
What commonly happens if the heart is compressed or imaged for long periods?
Heart rate can slow
What is being assessed in the 4 chamber view?
• Equal sized atria and ventricles respectively
• Foramen ovale flaps into LA• Moderator band in RV• TV more apical than MV• Ventricular septal defects• Atrial septal defects
What are the normal measurements of the IVS?
< 4 mm
What is the position and axis in the fetus?
• Transverse• Apex points toward left• RV lies toward sternum• LA lies toward spine• IVS ~ 45 degree angle from midline• Heart is approximately 1/3 the size of
the chest
What is levocardia?
Heart is mostly in the left chest(normal)
What is dextrocardia?
Heart is mostly in the right chest
What is mesocardia?
Heart is mostly midline
What is levoversion?
Apex pointed to the left(normal)
What is dextroversion?
Apex pointed to the right
What is mesoversion?
Apex pointed to the midline
How do you get the LVOT from 4 chamber?
Sweep anterior for 5 chamberTurn 45 – 90 degrees for PLAX
What is being assessed in the LVOT view?
• IVS for VSD• Continuity of IVS and Ao wall• Continuity of posterior Ao wall and
anterior MV leaflet• Ao root caliber
What is the normal Ao root caliber?
3 – 8 mm
In what view can the pulmonary trunk be measured?
RVOT
In the PSAX view what is being assessed?
• Spatial relationship between Ao & PA (should be equal)
• See the ductus between the PA and Ao• Branching of the 2 main pulmonary
arteries
What is the best view for great vessel transposition?
PSAX
What is the appearance of the ductus arteriosis from a sagittal view?
Like a hockey stick (less curved than the AA)
What is the first thing to come into the thoracic aorta?
Ductus arteriosis
What is the normal measurement of the aortic arch?
3 – 8 mm (20 – 40 weeks)
Never > 1 cm
What are the other structures that can be seen, but not routinely documented?
• Pulmonary vein• IVC• SVC
What is used to assess arrhythmias?
M-mode
What is used to assist in documenting blood flow?
Color Doppler
What plane is the diaphragm best seen in?
Longitudinal
What is to be visualized when looking at the diaphragm?
That the stomach is inferior and the heart is superior to the diaphragm
What is the site for abdominal measurement?
At the portal vein within the liver
When is the gallbladder in the right quadrant?
At 20 weeks
What is the appearance of the liver?
Midlevel gray and vessels seen within it
How is the abdominal circumference taken?
• Outer margin of skin• At the level of the left portal vein as J
or L from umbilical vein
What structures are seen when the AC is taken?
• Liver• Stomach• Possible adrenals
• ****NOT KIDNEYS
AC is most accurate in what trimester for weight?
3rd
When should the abdominal circumference be taken?
After 14 weeks
When can the stomach be seen?
After 12 weeks
What typically fills the stomach of the fetus?
Amniotic fluid
When can the kidneys be seen?
By 15 weeks
When do the kidneys begin to produce larger amounts of urine for amniotic fluid?
15 – 18 weeks
How do the kidneys appear in the 2nd trimester?
Ovoid with ill defined borders
How do the kidneys appear in the 3rd trimester
Borders and pelvis are more defined
What is pyelectasis?
When the kidney pelvis contains small amounts of fluid
With pyelectasis prior to 20 weeks, how much is considered insignificant?
< 5 mm
With pyelectasis between 20 – 30 weeks, how much is considered insignificant?
< 8 mm
With pyelectasis after 30 weeks, how much fluid is considered insignificant?
< 10 mm
What is being assessed with the bowel?
Echogenicity
Should be isoechoic to hyperechoic to liver
When can the bladder be seen?
By 14 weeks
How should the bladder appear?
Anechoic, if filled
If bladder fills and empties, what does this indicate?
Function of 1 kidney
How often does the bladder fill and empty?
Every 30 – 60 minutes
When should genitalia be documented?
When screening for congenitally linked disorders and multiple gestations
When can genitalia be seen?
15 – 16 weeks
Prior to 15 – 16 weeks how will labia appear?
Swollen
What is common to see in fetal testicles?
Hydrocele
When do the testicles descend?
28 weeks
Which extremities should be imaged?
All 4
What should be seen in the extremities?
• That all hands/feet are present• That hands extend• Assess foot bottom
How should the femus length be measured?
• Using the most anterior femur• Only the diaphysis
Is the femur length more or less affected by IUGR?
Less
Femur length is most accurate INDIVIDUAL measurement for dates/growth in what
trimester?
3rd trimester
When should the femur length be used?
After 14 weeks
When should the other long bones be measured?
If there is 2 weeks difference between femur length and other measurements
What accuracy are dating measurements in the 1st trimester?
+ / - 5 days
What accuracy are dating measurements in the 2nd trimester?
+ / - 10 days
What accuracy are dating measurements in 3rd trimester?
+ / - 20 days
How often should interval growth assessments be taken?
At least 2 weeks apart
How is fetal blood oxygenated?
The placenta
How does the fetus receive oxygenated blood?
Umbilical vein
How does the umbilical vein bypass the liver?
Through the ductus venosus
How does blood bypass the RV (lungs)?
Through the foramen ovale
Where does the LV pump blood to?
Aorta and brain
Where does blood entering the RV come from?
SVC and coronary sinus
Where does deoxygenated blood leave the fetus?
Via the umbilical arteries from fetal iliac arteries
What close when the umbilical cord is clamped at birth and the lungs fill with oxygen?
• Ductus venosus• Foramen ovale• Ductus arteriosis
How wide is the umbilical cord?
1 cm wide
What is the length of the umbilical cord?
40 – 60 cm
What is the layout of the umbilical cord?
The arteries spiral the larger vein
What is the likeliness of having only one umbilical artery?
• 1 % in singletons• 7 % in twins
When is it common to have only 1 umbilical artery?
• Diabetes• LBW
What surrounds the umbilical cord?
Wharton’s jelly(connective tissue)
What is the role of the placenta?
Permits exchange of oxygenated maternal blood with deoxygenated fetal
blood
What are the lobules of the placenta called?
Cotyledons
What is the functioning unit of the placenta?
Chorionic villi
Where are the villi?
Within intervillous spaces
What bathes the villi with blood?
Spiral areries
What forms the maternal portion of the placenta?
Decidua basalis – called the basal plate
What forms the fetal portion of the placenta?
Chorion frondosum – called the chorionic plate
When does the chorion fuse with the amnion?
By 16 weeks
Where does the umbilical artery branch?
Along chorionic plate of the placenta
What forms the umbilical vein?
The confluence of chorionic villi
What is the function of the placenta?
• Respiration• Nutrition• Excretion• Protection
• Microorganisms/rejection
• Storage• Carbohydrates• Protein• Calcium• Iron
• Hormone production (by syncytiotrophoblast cells)• hCG• Estrogen• progesterone
What is the sonographic appearance of the placenta?
• mid gray• Homogenous• Hyperechoic to uterus• Chorionic plate is more echogenic than
basal plate• Endometrial veins seen behind basal
plate
What is the normal width/thickness (AP) of the
placenta?
< 5 cm
What are some variants seen?
• Subplacental maternal venous congestion• Tubular vascular areas under the placenta in
myometrium
• Placental lakes/lacunae• Sonolucent/hypoechoic areas under, in, or on
the edge of the placenta• Slow vascular flow
• Myometrical contraction• Thickened hypervascular area under the
placenta
• Fibrin in intervillous spaces near basal plate of placenta
• 10 % develop calcifications
What should be assessed for the placenta?
• Location• Echogenicity• Entire length• Locate upper and lower margin• Placental grade
What describes placental grade 0?
Homogenous with smooth chorionic plate
What describes placental grade 1?
Scattered calcifications; subtle idention of chorionic plate, irregular brightness
What describes placental grade 2?
Basal echogenic calcification densities; comma like surface
What describes placental grade 3?
Irregular calcification densities with shadowing; subchorionic fibrin deposits, indentions go to basal plate – cumulus
clouds
What are the normal contents of amniotic fluid?
• Bilirubin• Fetal cells• Vernix caseosa• Fetal enzymes – AFP• Nutrients• Urea
What is the function of amniotic fluid?
• Fetal movement / prevents adherence• Symmetrical growth of fetus• Equalizes pressure
• Aids in lung maturity
• Consistent temperature• cushion
Where is amniotic fluid produced in the 1st trimester?
The placenta
Where is amniotic fluid produced after 18 weeks?
Kidneys
How should amniotic fluid be assessed?
• With the transducer perpendicular to the table
• Don’t include myometrium, cord loops or extremities
In 4 quadrant/amniotic fluid index what is considered low?
5 – 10 cm
In 4 quadrant/amniotic fluid index, what is considered normal?
10 – 20 cm
In 4 quadrant/amniotic fluid index, what is considered high?
20 – 25 cm
What is the normal range in a single pocket of amniotic fluid?
2.5 – 7.5 cm
What is fundal height in cm equal to?
Gestational age
When does quickening occur?
15 – 16 weeks
When does the fetus have daily movements?
16 – 20 weeks
What are the sonographic characteristics of placentomegaly?
• Placenta weighing >600 g• Thickness > 5 cm
What is a Succenturiate Placenta?
• Placenta w/ 1 or more accessory lobes
• Vessels may infarct & necrose• Associated w/ – Velamentous insertion– Vasa Previa
Sonographic Assessment of Succenturiate Placenta?
• Extra lobes w/ same echogencity• Ant. & Post. Placenta seen• Assess if connecting vessels overly cervix
Annular Placenta
• Forms like band or ring attached all the way around uterus
• Placenta Membranacea– No differentiation of trophoblastics into chorion
frondosum or laeve– Placenta villi retained may cover all GS– Amnion & chorion absent replaced by billy– Previa Association
Placenta Extrachorialis
• Edge of placental membrane lifts away from uterine wall and folded back on itself w/in amniotic space
• Portion not covered by chorionic plate • Sheet or shelf if severe
Circummarginate vs Circumvallate
• Circummarginate more likely– Fetal membrane insertion is flat
• Circumvallagte• Thickened rolled chorioamniotic membranes
peripherally
Signs of Placenta Previa
• Painless bright red bleeding • Premature contraction• Transverse fetal position
Sonographic Technique for Placenta Previa
• TV or transperineal• Contraction/Braxton Hicks• Lateral placenta most common false positive
Placenta Accreta
• Villi anchored/adherent to myometrium instead of decidua so absence of decidua basalis
Placenta Increta
• Villi implant into myometrium
Placenta Precreta
• Infiltrate past myomerium and implant in/past serosa of uterus
Appearance of Accreta, Increta, & Precreta
• Normal• Common location at Ant. lower uterine seg. • Large numerous placental lacunae• Turbulent flow at jxn b/w myometrium & placenta
w/ color• Hypoechoic interface b/w placenta & myometrium
obscure• Thinning of myometrium over placenta• Bulging or protrusion of placenta into bladder• Placenta heterogenous & thick• May present as ant. placenta previa in hist. c-sec.
Placental Cysts
• Anechoic structure appearing anywhere on surface of placenta
• Placental lakes-lacunae– Under chorionic plate– Irregular anechoic structures– Maternal pools of blood won’t demonstrate color
filling
Fibrin Deposits
• Hypoechoic regions w/in placenta containing strand like material
• Linear echogenic streaks w/in anechoic lesion• No vascular flow• From thrombosis from pooling & stasis of
maternal blood in perivillous & subchorionic spaces
Intervillous Thrombus
• Intraplacental hemorrhage or clot due to breaks in villi capillaries – Clot into cystic space w/ fibrin strangds
– RH sensitivity & increased AFP
Appearance of Intervillus Thrombus
• Hypoechoic to anechoic masses w/in placenta increase in size w/ maturity
• Cystic spaces w/ fibrin strands
Placental Infarcts
• Ischemic areas of necrosis when obstruction of the spiral arteries occurs
Teratomas(Placental Tumors)
• Benign, some malignant• Contain structures derives from the three
germ cell layers • Complex mass in placenta w/ calcification
possible
Chorioangioma (Placental Tumors)
• Benign tumor from proliferation of chorionic vessels
• Capillary hemangiomas• Can become an AV malformation shunting
blood away from the fetus • Associated w/ increased AFP and/or hCG
Worst Placental Hemorrhage?
• Retroplacental
• Least severe?– Paraplacental/Marginal