Smoking Cessation Interventions for Pregnant Women: Review and Future Directions Patricia O'Campo, Mary V. Davis, and Andrea C. Gielen

A substantial proportion of disease and death in the US could be prevented if tobacco use was curtailed or eliminated. Low birth weight, pregnancy complications, and infant morbidity are but a few of the adverse outcomes experienced by pregnant and postpartum women and infants that result from cigarette smoking. Pregnancy may be an ideal time to intervene with smoking women. On learning of their pregnancy, many women reduce or quit smoking on their own. For those who do not quit, interventions during the childbearing year could provide additional incentive and support for complete cessation. Successful clinic-based interventions share similar charac- teristics and tailoring cessation messages to client populations may enhance the effectiveness of interventions. Assessing a smoker's degree of addiction and tailoring counseling for cessation according to the patient's readiness might enhance current clinical practices. Even with the most effective individual counseling, it is increasingly evident that additional strategies are needed to achieve population-wide reductions in smoking and its related health conditions. Examples of these efforts are increased taxation on cigarettes, community-based anti-tobacco programs, and increasing the number of smoke-free environments. Thus, in addition to clinic-based efforts, health professionals might take an active role in supporting the broad range of programmatic, legislative, and advocacy efforts. Copyright �9 1 9 9 5 by W.B. Saunders Company

A substantial p ropor t ion of disease and death in the United States could be prevented if

tobacco use were curtailed or eliminated. Al- though smoking rates in the United States have shown a consistent decline over the last three decades, nearly one third of the populat ion still smoke cigarettes. Lower social classes are over- represen ted among smokers because rates of smoking have declined much faster among those in mid- and uppe r socioeconomic positions. More than 3,000 new smokers are recrui ted daily; the young, particularly young women, are being in- creasingly targeted by cigarette companies. 1'2 Approximately one in four women currently smoke. 3 Although historically women have had lower rates of smoking than men, women have recently exper ienced an increase in smoking-re- lated diseases. For example, in 1987, lung cancer surpassed breast cancer as the leading cause of cancer deaths among women of all ages. Table 1 presents a summary of potentially adverse health outcomes that result f rom smoking cigarettes.

Health Effects o f Smoking A m o n g Pregnant W o m e n

Infan t birth weight is one of the most important determinants of health and survival af ter birth.

Infants born in the low birth weight category (<2,500 g) are 40 times more likely to die in the neonatal per iod than normal bir th weight in- fants. 4 In 1992, 16.3% of Afr ican-American and 6.8% of white infants were born in the low birth weight category. 5 Low birth weight infants who survive the neonatal per iod may face fur ther short- and long-term health problems. Short- te rm complications of low birth weight include lower respiratory tract infections; long-term dif- ficulties include neurodevelopmental conditions, learning disorders, and behavioral problems. 4 Furthermore, the cost of health care for low birth weight infants is substantially greater, during and after delivery, than that for normal birth weight 4 infants.

Approximately 20% of pregnant women in the United States smoke th roughout their pregnan- cies.6 Maternal smoking during pregnancy is one

From the Departments of Maternal and Child Health and Health Policy and Management, Johns Hopkins School of Hygiene and Public Health, Baltimore, and Birch and Davis Associates Inc., Silver Spring, MD. Address reprint requests to Patricia O'Campo, PhD, Johns Hopkins University, 624 N Broadway, Room 189, Baltimore, MD 21205. Copyright �9 1995 by W.B. Saunders Company O146-0005/95/1904-0005505.00/0

Seminars in Perinatology, Vol 19, No 4 (August), 1995: pp 279-285 279

2 8 0 O'Campo, Davis, and Gielen

Table 1. Adverse Health Outcomes caused by Tobacco Use for Pregnancy and Nonpregnant Women, Infants, and Children During the Postpartum Period

Postpartum Infants and Pregnant Women Children Nonpregnant Women

Complications during pregnancy: placenta previa, abruptio placenta

Low birth weight Delivery Hospitalization

Infant mortali W

Sudden infant death syndrome (SIDS)

Colds, lower respiratory tract infections

Asthma

Developmental disorders Increased use of health

care services Hospitalizations

Colds, flu, other acute respiratory illnesses

Heart disease

Cancers: lung, oral, esophageal, cervical

Emphysema Increased use of the health care system

Osteoporosis Early menopause

of the most impor tant preventable risk factors of a low birth weight infant. 7 Maternal smoking decreases infant birth weight on average by 200 g, primarily through re tarding fetal growth after the 30th week of pregnancy. 8 Smoking dur ing the third t r imester o f pregnancy compromises fetal growth, p r i m a r i l y t h r o u g h intrauterine hypoxia. As a result o f smoking, carbon mon- oxide crosses the placenta and binds with both maternal and fetal hemoglobin to produce car- boxyhemoglobin, reducing the ability of the blood to carry adequate levels of oxygen to the fetus. 8

Maternal smoking may also indirectly com- promise fetal growth and bir th weight through affecting maternal nutrition. 8 Some researchers contend that p regnant women who smoke, eat less, and gain less weight during pregnancy result in deliveries of smaller infants.8 However, ob- served differences in weight gain dur ing preg- nancy between smokers and nonsmokers are rel- atively small and inconsistent across studies. Moreover, the relationship between maternal smoking and intrauterine growth re tardat ion (IUGR) remains af ter adjusting for maternal weight gain dur ing pregnancy. 8

Rationale for Intervening Prenatally

Women who quit smoking early in pregnancy can deliver infants comparable in weight and size to those of women who never smoked during preg- nancy, s'9 Infants born to women who quit smok- ing by the third t r imester o f pregnancy have higher bir th weights than infants born to women

who reduce smoking behavior, or who make no change in smoking during pregnancy. 9"1~ Results f rom observational and experimental studies also indicate that infants born to women who signif- icantly reduce smoking behavior dur ing preg- nancy benefit through increased birth weight. 9

An estimated 17% to 26% of low birth weight deliveries could be prevented by eliminating smoking altogether during pregnancy. 8 However, under the best circumstances, a conservative es- timate of quitting is about 8%. Therefore , apply- ing this estimate nationwide, approximately 1,920 low birth weight deliveries might be prevented, and $20 to $56 million might be saved annually 9, if widespread interventions were implemented.

Pregnancy may be an ideal t ime to intervene with smoking women. Many women, on learning of their pregnancy, reduce or quit smoking on their own. Most o f those who do not quit reduce their levels of smoking. Intervent ions during this per iod could provide additional incentive and suppor t for complete cessation. Unfortunately, after delivery, most women re turn to their orig- inal pat terns of smoking. 9'11-1~ Thus, prenatal in tervent ions , especially those coup led with pos tpar tum reinforcements, may prevent the substantial relapse that of ten occurs.

In addition to the health benefits to the fetus and infant gained by smoking reduct ion or ces- sation during pregnancy, cessation also leads to improved long-term health of the woman. The two leading causes of death for women, heart disease and cancer, occur more frequently and at a younger age for smokers. 14 Women who smoke are at increased risk for complications of

Smoking Cessation Interventions 281

oral contraceptive use, early menopause, cervical cancer, osteoporosis, emphysema, and cardio- vascular disease. ~'15 Women who quit smoking permanently by middle age substantially reduce their risk of heart disease and lung cancer in their later years. Because most women come into rou- tine contact with the health care system during pregnancy, smoking cessation during pregnancy can potentially play a significant role in improving maternal and child health.

Helping Pregnant Women to Stop Smoking

Although 90% of all smokers would like to quit, permanent smoking cessation is difficult for many smokers to achieve. 16 Over the past 25 years, methodologies for promoting smoking cessation during the prenatal period have undergone great changes.l 7 For example, counseling methods are now coupled with pharmacological agents, such as nicotine gum or the nicotine patch, to increase the likelihood of permanent cessation in non- pregnant women, is The nicotine patch has not been tested in pregnant women, although is the U.S. Food and Drug Administration has asked companies to conduct trials in this area as part o f post-marketing study.

Although counsCing all pregnant smokers to quit is recommended, the extent to which this counseling takes place is not dear. 4's Studies in other medical care contexts suggest that effective behavioral counseling of smokers by physicians rarely occurs. 19 In some of our own work, we have found that, even in the context of a clinical trial tha~: included provider participation, 20% of pregnap_t women reported that their provider never, or o~.~y once, mentioned smoking cessation during pregnancy. ~

Effectiveness of S ~ o k i n g Cessation Interventions

Over the last few decades, numerous studies have been conducted in the United States on smoking cessation among pregnant women, most of which have been observational. 1~ These studies have identified correlates of cessation which show that women with particular demographic prof i les - - married, young, better educated---are more suc- cessful at quitting during pregnancy without the assistance of an intervention, s Other groups who

are more likely to quit smoking during pregnancy include those who receive care from a private physician, smoke fewer than 10 cigarettes per day, start smoking later in life, have fewer chil- dren, and have no other smokers in the house- hold. a

Observational studies also suggest that per- manent cessation may be most likely among teen mothers. Most adult smokers began using to- bacco by the age of 18 years. 2~ Within the first years of smoking, while the individual is adopting the behavior, smoking levels are lower, and ad- diction to nicotine is less strong. Therefore, ad- olescent smokers who are pregnant may be most receptive to intervention and may be able to achieve permanent cessation. 21

Because observational studies cannot avoid the problem of selection bias (ie, those women who are most motivated being either more compliant or selecting to be in the intervention group), they are a weak design for determining the impact of cessation interventions on smoking behavior. Conversely, findings from randomized clinical trials (RCTs) can provide valuable information for designing future programs and individualiz- ing care to help pregnant women to stop smok- ing.

Randomized Clinical Trials

There have been 10 US-based randomized clinical trials of smoking cessation during preg- nancy. 9'11'2227 Overall, most clinic-based inter- ventions rely on self-help materials with coun- seling from a health educator or counselor. Price et al26 used an educational video, Petersen et a127 used an audiotape, and a more intensive inter- vention had monthly phone contact and biweekly mail contact with intervention clients. Overall quit rates in the treatment groups ranged from 4.9% to 31.9%; among control groups quit rates ranged from 1.4% to 17.2%. Quit rates did not appear to vary by the intensity of the intervention activity, in the Sexton and Hebel RCT, 22 the quit rates were the highest, at 31.9%. For example, in one clinical trial in which the intervention in- cluded a mailed self-help manual and audiotape, the quit rate in the treatment group was 16.3%. In another clinical trial in which the intervention was composed of interaction with a health edu- cator and either an educational videotape plus a self-help pamphlet or a self-help booklet, the quit

282 O'Campo, Davis, and Gielen

rate was 4.9%. Although not uniformly available for all studies, the socioeconomic status of the client populat ion may have been an important factor in the quitting patterns. For example, health maintenance organization (HMO) popu- lations appear to have higher quit rates than do public clinic populations. 2s

Enhancing the Effectiveness of Smoking Cessation Intervention~

Smoking cessation intervention trials for preg- nant women have demons t ra ted that, in the ag- gregate, part icipants have been able to reduce smoking significantly and improve on the prob- lem of low birth weight. Nonetheless, the sub- stantial variation in the effectiveness of the array of intervention strategies that have been evalu- ated suggests that there is no single intervention that can be r e c o m m e n d e d for universal adopt ion by prenatal care providers. There are, however, common elements of successful interventions that have emerged f rom .research.

The populat ions of p regnant smokers studied have been he terogeneous with regard to demo- graphic and cultural background. Given what is known about the predictors of smoking cessation (regardless of intervention), women with differ- ent backgrounds can be expected to have differ- ent reasons for continuing or quitting smoking. In fact, in our own research, we found that Af- r ican-Amer ican women f rom different geo- graphic regions have different predictors of smoking cessation and reduct ion during preg- nancy. 21 Clinical trials of the same self-help in- tervent ion (with counseling and reinforcement) achieved very different results among Afr ican- American women in Birmingham, Alabama, and Baltimore, Maryland. In Birmingham, the inter- vention g roup quit rates were 1 8.1%, compared with 10.7% in the control g roup (P = .03). ~ In the Baltimore study, the intervention group quit rates were 6.2%, compared with 5.6% in the con- trol group.51 The discrepant findings may be at- tr ibutable in par t to sociodemographic charac- teristics and smoking pat terns between the two samples. 9,11,21

These findings are consistent with health be- havior change theory and experience that suggest the effectiveness of interventions depends on the match between the needs of a specific target au- dience and the type of intervention provided. 29'3~

This does not mean that every provider needs to start de novo in planning a smoking cessation p rog ram that is unique to the specific target au- dience, but ra ther that meaningful needs assess- ment and formative evaluation should be under- taken before a p rogram is impor ted or planned. For example, discussion groups or individual in- terviews with smokers are low-cost strategies that can yield impor tant insights into a target audi- ence 's concerns about quitting and perceived needs for help, as well as provide feedback on the acceptability and potential effectiveness of p rogram plans. Professional health educators who are trained in these program-planning skills are useful resource people for clinicians who are considering implementing smoking cessation in- terventions.

Based on the findings of evaluation studies re- viewed in the previous section, certain general features should be included in any intervention. Dolan-Mullen et al's meta-analysis 2s concluded that (1) effectiveness is enhanced by using ma- terials that are specific to pregnant women rather than those written for a more general audience, and (2) multiple methods (eg, counseling, written materials, follow-up) are superior to "one-shot" approaches.

Any smoking cessation p rogram for pregnant women should encourage a policy of "no smok- ing" in the woman's home. Not only will this eliminate one source of stimulus to smoke, and thus make cessation easier for the woman, it will also have the added health benefit of reducing exposure to second-hand smoke, which is a sig- nificant source of carbon monoxide exposure for many pregnant w o m e n . 9'21'31 Our own data show that a woman 's cotinine level, af ter adjusting for the n u m b e r of cigarettes smoked per day, is sig- nificantly influenced by her exposure to passive smoking resulting f rom allowing people to smoke in the home. 31

The clinician should assess the patient 's degree of addiction and readiness to quit smoking as a part o f taking a pregnant woman 's medical his- tory. For example, Fagerstr/Sm et al have an in- s t rument which takes a few minutes to administer that could be used to assess degree of addiction. Table 2 presents some questions f rom the Fa- gers t r6m assessment tool. 32 Addiction assess- ments could also be conducted effectively by a trained health education professional.

Based on the answers to Fagers t r6m's test, the

Smoking Cessation Interventions 283

Table 2. Addiction Assessment Questions

1. How soon after you wake up do you smoke your first cigarette?

2. Which cigarette would most you hate to give up? 3. How many cigarettes do you smoke per day?

patient is rated as having a very low, low, medium, high, or very high degree of addiction. Once the degree of addition is determined, the appropriate means of intervention can be" identified. For ex- ample, women who have a high or very high de- gree of addiction to cigarettes--those who either smoke their first cigarette within the first 30 min- utes of waking, would hate to give up their first cigarette of the day, or smoke more than 10 cig- arettes a d a y - - a r e unlikely to be able to quit with self-help methods alone. Rather, considerable reinforcement would be required. Not all pa- tients, especially those with h igh degrees of ad- diction, will be ready to quit when presenting for prenatal care. Clinicians therefore could further assess the patient 's readiness to quit smoking in addition to the degree of addiction.

The stages of change (SOC) approach 33 could be used to assess readiness to quit. SOC acknowl- edges that smokers when presented with an op- portunity to quit smoking vary in their willingness and capability to quit. The first column of Table 3 lists the five stages of change for addictive be- haviors. Certain smokers are "precontempla- ters," not even considering quitting, when they enter care. Other smokers are "contemplat ing" quitting when they are presented with an oppor- tunity. Although they are considering quitting, they have not yet initiated an action plan to quit. Counseling for such individuals may involve dis- cussions about the pros and cons of stopping smoking. Smokers who are "ready for action" when they enter care are planning to make a quit

attempt in the immediate future and are most open to clinician counseling on methods to stop smoking.

Smokers who are making an active attempt to quit cannot be considered former or ex-smokers because most smokers require several quit at- tempts before they can be considered quitters. An individual who has remained smoke free for a year, can be considered a former smoker, but he or she may relapse and smoke again given cer- tain circumstances.

Patients at different stages of readiness to quit require different kinds of counseling from their physicians. Precontemplaters should be coun- seled to consider quitting, and contemplators should be counseled to plan to make an active quit attempt. Smokers ready for action should be encouraged to make an action plan for quit- ting; those smokers who are actively making a quit attempt should be encouraged and sup- ported in their attempt. 33 Tailoring counsel for cessation according to the patient's readiness to quit is an effective method to begin the process of achieving permanent cessation.

There have been no interventions designed to specifically take into account a woman's degree of addiction and readiness to quit. Adoption of such an approach, however, might enhance the effectiveness of smoking cessation interventions. In the meantime, screening pregnant smokers for the degree of addiction and readiness to quit may help identify women who will benefit f rom spe- cific types of interventions. For example, a sim- ple, low-cost intervention (eg, brief counseling with printed materials) can be effective among those women identified as light smokers (fewer than 5 to 10 cigarettes per day), women who have thought about or tried quitting since becoming pregnant, and women who express some confi-

Table 3. Stages of Readiness to Quit Smoking

Stage Definition Intervention

Precontemplative

Contemplative

Ready for action Action

Maintenance

Has not thought of quitting smoking

Has considered quitting but not yet acted

Plans to make a quit attempt in near future Has been off cigarettes for several weeks

Has maintained quit status for several months

Raise level of awareness about the need to quit

Elicit feelings--pros, cons, concerns-- about quitting

Build confidence in commitment to quit Reward successful attempt and reinforce

commitment to stay quit Support continued commitment to stay

quit

284 O'Campo, Davis, and Gielen

Table 4. What Health Professionals Can Do to Help Pregnant Women Quit Smoking

Clinical Settings Community Settings

Assess the smoking his tory o f all female pat ients , inc lud ing adolescents

Counse l all smoking pa t ien ts to qui t or at least to beg in the process of cessat ion

S u p p o r t the cessat ion effor ts o f all pat ients , especially d u r i n g an active qui t a t t em p t

Use in t e rven t ions and messages tha t are a p p r o p r i a t e for your pa t i en t p o p u l a t i o n

Contact the local medical society and encourage the organization to be active in tobacco control efforts

Volunteer to testify in legislative and administrative hearings during which tobacco control measures are being considered

Contact the local health department to volunteer for tobacco control activities

Contact the local school system to volunteer for presentations to youth on avoiding tobacco use

dence in their ability to quit. Alternatively, a more intensive intervention (eg, additional follow-up counseling) is probably needed for those women who do not share these characteristics.

Environmental Factors Affecting a Pregnant Woman's Ability to Stop Smoking

It is important for clinicians to recognize the complex process of smoking cessation. Factors that substantially affect a woman's ability to achieve cessation include the presence of other smokers in her household, workplace policies re- garding smoking, and living in communities that are targeted by the tobacco companies with pro- smoking messages (ie, billboards). Even with the most effective individual counseling, it is increas- ingly evident that additional strategies are needed to achieve population-wide reductions in smoking and its related health conditions. 1'~~ For ex- ample, in Canada during the 1980s, when gov- ernment legislation was more vigorous and cig- arette taxation was higher in comparison with the United States, rates of tobacco consumption also declined faster. ~6 In Canada federal and local taxes constituted two thirds of the total price of a pack of cigarettes, whereas in the United States combined state and federal taxes constituted 20%. The Canadian government has also passed various legislation that restricts tobacco promo- tional activities, bans tobacco product advertis- ing, and implements economic programs to help tobacco growers leave the industry. ~6 Similar ef- forts are beginning in the United States. For ex- ample, the California Proposition 99 effort in- cluded a multimedia campaign and a $ .25/pack cigarette tax increase. This resulted in a tripling o f the rate at which cigarette consumption de- clined. 3~ American Stop Smoking Intervention

Study for Cancer Prevention (ASSIST), funded by the National Cancer Institute, and Initiative to Mobilize for the Prevention and Control of Tobacco Use (IMPACT), funded by the Centers for Disease Control and Prevention, are tobacco control efforts designed to change environmental factors that affect tobacco use, such as increasing the number of tobacco-free environments or even targeting community norms about smoking.

Health professionals can take an active role in supporting these multifaceted education and ad- vocacy efforts. Table 4 presents a broad range of activities that health professionals may engage in to prevent initiation of smoking or to promote smoking cessation. In addition to these activities, health professionals may become active in pro- moting institutional changes within their own workplaces to promote smoking cessation ef- forts. ~7 As pointed out by Wynder, 35 "profes- sionals need to match the commitment and ex- pertise of therapeutic medicine with an equal emphasis on health promotion." Because of their high public credibility and potential political im- pact, it is imperative that health professionals be- come involved in supporting tobacco control ef- forts in their communities.

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