Because cigarette smoking is a major preventable cause of poor pregnancy outcome, reducing tobacco use by pregnant women is a public health priority.1 After a infant’s birth, smoking cessation remains a goal to protect the infant from secondhand smoke exposure and its mother from tobacco-related health risks.2,3 Brief behavioral counseling at a prenatal visit is effective and is the standard prenatal practice, but it produces modest smoking cessation rates.4–6 Adding a smoking cessation medication to counseling is a standard component of evidence-based tobacco dependence treatment in nonpregnant smokers.7 Medication might also improve the smoking cessation rates achieved by pregnant and postpartum women, but smoking cessation medication use by pregnant and breastfeeding women is limited by uncertainty about its safety and efficacy in this clinical setting.8
Few data in humans are available to guide obstetric practice. No randomized controlled trial has demonstrated the efficacy of either nicotine replacement or bupropion specifically during pregnancy (Miller H, Ranger-Moore J, Ningtgen M. Bupropion SR for smoking cessation in pregnancy: a pilot study [abstract]. Am J Obstet Gynecol 2003;189:S133),6,8–12 although trials are ongoing.13,14 Limited evidence from clinical trials in humans does not indicate that nicotine replacement therapy harms a fetus,9,15–17 but animal studies suggest that nicotine may be teratogenic to fetal neurons and raise concerns that nicotine exposure in utero could have neurodevelopmental consequences in children.8,12 Bupropion has no known teratogenic effects, but human data are limited and bupropion increases seizure risk.8
In the absence of definitive data, expert reviews have concluded that the risk/benefit profile for the use of nicotine replacement or bupropion in pregnancy is favorable.8,11,12,18 The risk-benefit ratio is especially favorable for heavier smokers (more than 10 cigarettes/day) because they expose the fetus to higher doses of nicotine, carbon monoxide, and other toxins and because they are less likely than lighter smokers to quit in pregnancy, even with counseling. Clinical practice guidelines in the United States and Britain recommend nicotine replacement for pregnant smokers, especially heavy smokers, who have not quit with nonpharmacologic treatment, so long as the dose of nicotine received from nicotine replacement therapy is not larger than what would have been received by smoking cigarettes.7,19,20 Bupropion has a similar recommendation in U.S. but not in British clinical guidelines.20 Nicotine replacement products are licensed in Britain for use by pregnant and breastfeeding women.21
In this situation of clinical uncertainty, obstetric providers must decide whether to recommend smoking cessation medications to pregnant and breastfeeding women, and pregnant and postpartum women must decide whether to use them. Little is known about what decisions are made in actual practice. In prior surveys, 26–44% of American and British obstetric providers said that they recommended nicotine replacement to pregnant smokers.22–25 How often providers discuss bupropion with pregnant smokers or any cessation medication with breastfeeding smokers is unknown. No data are available from pregnant women about their own medication use. This study fills these gaps by providing evidence about current clinical practice in a large group of pregnant smokers who were interested in stopping smoking. It addresses these questions: 1) How often do obstetric providers discuss smoking cessation medications (nicotine replacement or bupropion) with pregnant and postpartum smokers? 2) With which smokers do obstetric providers discuss cessation medications? 3) What proportion of pregnant and postpartum smokers use a smoking cessation medication? 4) Which pregnant smokers are most likely to use a smoking cessation medication? We hypothesized that if current practice follows expert consensus and clinical practice guidelines, medications would be used more often by heavy smokers (more than 10 cigarettes/day) and by smokers who had already made an unsuccessful attempt to quit during pregnancy.
MATERIALS AND METHODS
We analyzed data from a randomized controlled trial of pregnant smokers that compared the efficacy of multi-session telephone counseling to a “best practice” single-session counseling control. The study design and methods have been described.26 The study was approved by the Institutional Review Board of Partners Healthcare System, Inc. During 2001–2004, 442 pregnant smokers were recruited from obstetric providers and from a prenatal care plan in Massachusetts. Eligible smokers were more than 18 years old, at less than 26 weeks of gestation, had smoked in the past 7 days, and were willing to consider changing their smoking practices but did not have to commit to quitting. Women were assigned to treatment condition by using a computer-generated list stratified by referral source. The intervention group received multiple telephone calls during pregnancy, during which cognitive-behavioral smoking cessation counseling was provided. The control group received one short counseling call. Smoking cessation medication was not discussed in either study arm, and patients who asked about medication were advised to discuss medication with their doctor.
A telephone interview at study entry assessed age, race, education, marital status, and health insurance, parity, and smoking measures, including daily smoking rate, time to first morning cigarette (a measure of nicotine dependence),27 number of 24-hour quit attempts since becoming pregnant, intention to quit during pregnancy,28 perceived risks of smoking in pregnancy, and self-efficacy (confidence in the ability to quit in the next month). Outcomes were assessed by telephone interview at end of pregnancy (28 weeks of gestation or later) and 3 months postpartum. At end of pregnancy, women were asked whether a prenatal provider had discussed smoking cessation methods during pregnancy and whether they had “done any of the following to help themselves try to quit or stay off cigarettes during pregnancy.” At the postpartum assessment, “since your baby was born” was substituted for “during pregnancy.” At both times, separate questions asked about the use of nicotine gum, nicotine patches, bupropion, and nonpharmacologic methods (group quit-smoking program, one-to-one quit-smoking program, quit-smoking guide or video, hypnosis, or acupuncture).
Obstetric providers’ behavior was assessed by asking patients a series of questions beginning with, “Since you started prenatal care, has your doctor or any member of the clinic staff talked with you about using _______ to help you quit?” Pharmacologic options were nicotine gum, nicotine patch, and bupropion. Nonpharmacologic options were “given you quit smoking materials” and “referred you to any stop smoking program to get personal counseling or support.” Patients were also asked if a prenatal provider had “talked with you about trying to quit smoking” and “talked with you about different methods available to quit smoking.” At 3 months postpartum, women were asked if they had seen their prenatal provider since delivery. If so, they were asked if the doctor or clinic staff had discussed smoking cessation medications.
At both follow-up points, smoking status (7-day point prevalence abstinence) and quit attempts of 24 hours or more since becoming pregnant or since delivery were assessed. The postpartum survey assessed whether the respondent had breastfed her infant since delivery. Respondents who reported tobacco abstinence were asked to provide a saliva sample by mail. Validated abstinence was defined as a self-report of abstinence for the past 7 days confirmed by a salivary cotinine less than 20 ng/mL. All other patients were classified as smokers for analysis.
Data from the two study arms were combined for these analyses, because smoking cessation medication was not part of the protocol in either arm and because rates of medication use did not differ by study arm (end of pregnancy: 9.9% compared with 10.4%, P=.88; 3 months postpartum: 12.8% compared with 12.6%, P=.97). Rates of use of pharmacologic and nonpharmacologic smoking cessation methods during pregnancy were calculated for all respondents to the end-of-pregnancy survey. Postpartum rates of pharmacologic and nonpharmacologic cessation treatment use were calculated for all respondents to the postpartum survey who smoked at any point after delivery. The analysis of providers’ actions to address tobacco use postpartum was limited to smokers who had made a postpartum visit to their obstetric provider. Chi-square tests were used to compare categorical outcomes among different groups. McNemar tests were used to assess significance of differences in use of cessation methods. Univariable and multiple logistic regression analyses were done to identify the characteristics of 1) smokers who used cessation medication during pregnancy, 2) smokers who used cessation medication postpartum, and 3) smokers who discussed medication use with their obstetric provider during pregnancy and postpartum.
The end-of-pregnancy assessment was completed by 308 (73%) of the 421 women who carried their pregnancies to term. Analyses are based on the 296 respondents who answered the questions about use of smoking cessation methods. The 3-month postpartum assessment was completed by 293 patients (70% response rate), of whom 259 (88.4%) had smoked since delivery, and 234 answered questions about smoking cessation methods used after delivery.
Patients’ mean age was 29 years; 87% were white, 73% were married or living with a partner, and 45% were nulliparous. They had an average of 13 years of education and entered the study at a mean of 13 weeks of gestation. Patients had smoked a mean of 21 cigarettes daily before becoming pregnant and a mean of 10 cigarettes daily at study enrollment. Eighty-three percent planned to stop smoking in the next 30 days. At the end of pregnancy, 68.6% of respondents reported having made a quit attempt of 24 hours or more since becoming pregnant (control 70.4%, intervention 66.7%). Among survey respondents, the validated smoking cessation rate was 12.5% at end of pregnancy (control 10.5%, intervention 14.6%, P=.37) and 9.7% at 3 months postpartum (control 9.9%, intervention 9.4%).
At the end of pregnancy, 79.5% of respondents reported that their prenatal provider had talked with them about trying to quit smoking, and 43.6% of providers had discussed methods of stopping smoking with them (Fig. 1). Providers were less likely to discuss pharmacologic than nonpharmacologic smoking cessation methods; 29.3% of respondents reported that their obstetric provider had discussed using any cessation medication during pregnancy, whereas 45.6% reported being offered a nonpharmacologic cessation aid (booklet or referral to a stop-smoking program) (P<.001). Nicotine replacement was discussed by providers more than twice as often as bupropion (26.5% compared with 12.2%, P=.001). Women whose obstetric providers discussed smoking cessation medication use during pregnancy did not differ from those whose providers did not discuss medications in parity, race, education, cigarettes smoked per day, degree of nicotine dependence, history of an unsuccessful 24-hour quit attempt during the current pregnancy, or health insurance (public or private). The only difference was age, which was higher in women whose providers discussed medications (mean 29.9 compared with 27.9 years, P=.01).
At 3 months postpartum, 259 (88.4%) of 292 respondents reported having smoked since delivery, and 84.6% (n=219) of the 259 smokers had made a postpartum visit to their obstetric providers. At that visit, the provider talked with 48.3% of the smokers about trying to quit and discussed any smoking cessation medication with 29.4% of the smokers (Fig. 1). Nicotine patch or gum was discussed with more smokers than was bupropion (23.4% compared with 16.5%, P=.019). A smoker’s breastfeeding status did not affect her provider’s likelihood of discussing the use of a smoking cessation medication. Obstetric providers discussed smoking cessation medications with 28.3% of those who did not breastfeed, 27.3% of women who were currently breastfeeding, and 32.0% of those who had breastfed but stopped (P=.83).
A smoking cessation medication (nicotine patch, nicotine gum, or bupropion) was used by 10.1% of respondents during pregnancy and by 14.3% of smokers in the 3 postpartum months. Table 1 displays the rates at which the specific smoking cessation medications and other cessation methods were used during pregnancy and in the early postpartum period. During pregnancy, nicotine replacement was used more than twice as often as bupropion (7.4% compared with 3.4%, P=.023), but bupropion use increased after delivery so that there was little difference at 3 months postpartum (8.8% compared with 7.1%, P=.47).
Overall, 18.9% of respondents reported having used any smoking cessation assistance during pregnancy beyond what was provided in the trial. They were no more likely to use a nonpharmacologic cessation aid during pregnancy (12.5%) than to use a medication (10.1%). Hypnosis was the most popular nonpharmacologic aid. The proportion of smokers who used any smoking cessation assistance during the 3 months postpartum (19.3%) was similar to the rate of assistance during pregnancy (18.9%). The rate at which nonpharmacologic aids were used was marginally lower after birth than during pregnancy (8.0% compared with 12.5%, P=.067).
As shown in Table 2, using a smoking cessation medication in pregnancy was associated (P<.05) with being older, better educated, living with a partner, having a prior childbirth, having an obstetric provider who discussed medication use, and having private health insurance (in a state where public insurance did not pay for cessation medications at the time of the study). For each specific medication examined (nicotine patch, nicotine gum, bupropion), there was a statistically significant association between a provider’s discussion of that specific medication and a pregnant smoker’s use of that medication (data not shown). Smoking cessation medication was not used more often by women who smoked more heavily, were more nicotine dependent, or had already tried to quit during pregnancy, as clinical practice guidelines recommend.
The small number of outcomes (ie, number of women who used medication; n=30) limited the number of independent predictors that could be included in a multiple logistic regression analysis without overfitting the model. Therefore, we tested a series of multivariable models, each of which included the independent variable of provider discussion of medication with the patient (the independent variable of most interest) and one of the other factors that was associated with medication use in the univariable analysis (age, education, marital status, parity, type of health insurance). In each of these multiple logistic regression models, provider discussion of cessation medication consistently and significantly increased the odds that a pregnant woman would use a cessation medication, with odds ratios varying from 5.37 to 6.76. Each of the other factors was also statistically significantly associated with cessation medication use after adjustment for provider discussion of cessation medication.
A second set of multiple logistic regression models tested whether the type of health insurance (private or public) was independently associated with each of the other factors associated with medication use in the univariable analysis. Having private (as opposed to public or other) health insurance increased the odds of using a smoking cessation medication during pregnancy, independently of education, parity, age, and whether the obstetric provider discussed medication use. Odds ratios (private compared with public/other insurance) ranged from 3.28 to 4.92. Each of the other factors was statistically significantly associated with cessation medication use after adjustment for health insurance type, except for marital status.
In a univariable analysis, three factors increased the likelihood that a postpartum smoker would use a smoking cessation medication: older age (mean 31.6 compared with 28.5 years, P=.008), smoking more cigarettes daily before pregnancy (mean 23.8 compared with 20.3, P=.031), and having discussed smoking cessation medication with the obstetric provider at the postpartum visit (65% compared with 23%, P<.001). Having a provider who discussed smoking cessation medication use at the postpartum visit was strongly associated with postpartum medication use in a multiple logistic regression model that adjusted for age (odds ratio [OR] 6.3, 95% confidence interval [CI] 2.8–14.0) and in a second model that adjusted for cigarettes smoked per day (OR 6.5, 95% CI 2.9–14.5). In each model, age and prepregnancy daily smoking rate were independently associated with postpartum medication use.
Whether to recommend smoking cessation medication to pregnant smokers is a common clinical dilemma faced by prenatal care providers. Neither nicotine replacement nor bupropion has been proven safe and effective in pregnant women, but the unequivocal harm of continued smoking has led experts and clinical practice guidelines to recommend that medications be considered after nonpharmacologic treatment fails. Little is known about what decisions practitioners and pregnant women actually make. This study fills that gap. In a large sample of pregnant smokers who were interested in quitting smoking, only 29% reported having discussed a smoking cessation medication with their obstetric providers. Even fewer of the women (10%) actually used either nicotine replacement or bupropion during pregnancy. Nicotine replacement was discussed by providers and used by smokers twice as often as bupropion. Providers discussed nonpharmacologic treatment with smokers more often than they discussed drugs, but practice patterns did not appear consistent with clinical guidelines that recommend considering medication for heavier smokers and for smokers who fail nonpharmacologic treatment.
Using patient reports, this study assesses the rate at which smokers use a smoking cessation medication during pregnancy or in the immediate postpartum period. Prior studies of pregnant smokers have only assessed women’s potential interest in using nicotine replacement,29,30 or in enrolling in a nicotine replacement trial,31 not their actual medication use. The proportion of pregnant smokers in these surveys who expressed interest in nicotine replacement was much larger than the 10% who actually used a medication in our study. Although not the focus of the study, our surveys found a relatively high rate hypnosis for smoking cessation during pregnancy, despite the fact that practice guidelines with meta-analyses of hypnosis for smoking cessation have not found it to be effective in nonpregnant smokers.7
This study is also the first to report on how often smoking is addressed at the postpartum obstetric visit. The rates of smoking cessation medication discussion and use after delivery were similar among women who made a postpartum obstetric visit. Obstetric providers did not appear to be deterred from discussing medication use by women’s breastfeeding status. However, the wording of the survey question does not allow us to infer that a discussion of medication use with breastfeeding smokers constituted an endorsement of the practice.
Our study also provides new information about which smokers are likely to use a cessation medication during pregnancy. Contrary to our hypothesis based on current guidelines, medication use was not higher among heavier, more nicotine-dependent smokers or among smokers who had already tried and failed to quit during pregnancy. Instead, pregnant smokers were more likely to use a cessation medication if their prenatal provider discussed these medications with them or if they had private health insurance. These data suggest that two remediable barriers to greater use of cessation medications in pregnancy are clinicians’ failure to discuss medication use and lack of health insurance coverage for smoking cessation medications. Nicotine replacement and bupropion were covered by several large private health insurance plans during the study period, but Massachusetts’ Medicaid program covered no cessation treatment.
The current study also provides new information about how often prenatal providers discuss cessation medications with pregnant smokers. Most prior surveys that assessed prenatal providers’ actions to address smoking did not ask whether they recommend or use cessation medication.32–36 The four prior studies that assessed medication use did so by asking prenatal providers about their usual practice,22–25 whereas our study assessed provider behavior through the reports of patients rather than by the report of providers themselves. Nevertheless, our results are similar to three prior studies in which 26% of 154 Ohio obstetricians, 29% of 607 Texas obstetricians, and 27% of 368 British general practitioners reported that they prescribed nicotine replacement in pregnancy.22,23,25 Our estimate is lower than the 44% rate of nicotine replacement therapy prescription or recommendation reported by a small study of 61 obstetric providers in Massachusetts community health centers.24
This study has several limitations. First, the survey asked pregnant women only whether their obstetric provider had discussed smoking cessation medications. Women were not asked about the content of these discussions. We cannot determine whether the prenatal provider recommended or discouraged medication use during pregnancy, and we do not know whether the patient or the provider brought up the topic of smoking cessation medication. Therefore, our estimates of the rate at which obstetric providers discussed cessation medications cannot be interpreted to represent the rates at which obstetric providers recommend or prescribe them. Furthermore, it is possible that practitioners considered pharmacotherapy use but did not think it appropriate for the patient and, therefore, did not discuss medication use with them.
Another limitation is that the study sample was drawn from pregnant women living in one state who enrolled in a smoking cessation trial. Therefore, the results are not generalizable to all pregnant women or to other geographic areas. Because women had to be interested in changing their smoking behavior to be eligible for the trial, the rates of medication use reported here may be higher than would be found in another population-based sample of pregnant smokers. However, this potential bias is likely to be small because the large majority of pregnant smokers profess an interest in stopping smoking.3
In summary, in this large sample of pregnant smokers who were interested in quitting, only 3 in 10 women recalled that any prenatal provider discussed the use of a smoking cessation medication, and only 1 in 10 women actually used a cessation medication. Both obstetricians and pregnant women appear to be more reluctant to consider cessation medications than clinical guidelines recommend. Presumably, the reluctance is attributable to a desire to limit medication use in pregnancy and to the lack of data proving the safety and efficacy of nicotine replacement or bupropion in pregnancy. Clinical trials are clearly needed to provide the safety and efficacy data. Until more is known, clinical guidelines and expert reviews have weighed this uncertainty against the known harms of continued smoking in pregnancy and encourage consideration of medication use in certain circumstances, especially when the risk/benefit ratio is very favorable.7,8,11,18,19 At present, both providers and patients appear to have a more conservative view. Our data strongly suggest that pregnant women would be more likely to use a smoking cessation medication in pregnancy if their obstetric providers routinely discussed these medications with them and if health insurers covered the cost of these medications. These actions could help narrow the existing gap between clinical practice and clinical guidelines and reduce the tobacco-related harms to women and their children.
1. Centers for Disease Control and Prevention. Tobacco use. In: U.S. Department of Health and Human Services, ed. Healthy people 2010: with understanding and improving health and objectives for improving health. Vol 2. 2nd ed. Washington, DC: U.S. Department of Health and Human Services; 2000. p. 1–40.
2. U.S. Department of Health and Human Services. The health consequences of involuntary exposure to tobacco smoke: a report of the surgeon general. Rockville (MD): U.S. Department of Health and Human Services, Public Health Service, Office of the Surgeon General; 2006.
3. U.S. Department of Health and Human Services. Women and smoking: a report of the surgeon general. Rockville (MD): U.S. Department of Health and Human Services, Public Health Service, Office of the Surgeon General; 2001.
4. Melvin CL, Dolan-Mullen P, Windsor RA, Whiteside HP Jr, Goldenberg RL. Recommended cessation counselling for pregnant women who smoke: a review of the evidence. Tob Control 2000;9 suppl 3:III80–4.
5. Smoking cessation during pregnancy. ACOG Committee Opinion No. 316. American College of Obstetricians and Gynecologists. Obstet Gynecol 2005;106:883–8.
6. Lumley J, Oliver SS, Chamberlain C, Oakley L. Interventions for promoting smoking cessation during pregnancy. Cochrane Database Syst Rev. 2004;(4):CD001055.
7. Fiore MC, Bailey WC, Cohen SJ, Dorfman SF, Goldstein MG, Gritz ER, et al. Treating tobacco use and dependence: clinical practice guideline. U.S. Department of Health and Human Services; 2000. Available at: www.surgeongeneral.gov/tobacco/treating_tobacco_use.pdf
. Retrieved October 23, 2007.
8. Benowitz N, Dempsey D. Pharmacotherapy for smoking cessation during pregnancy. Nicotine Tob Res 2004;6 suppl 2:S189–202.
9. Wisborg K, Henriksen TB, Jespersen LB, Secher NJ. Nicotine patches for pregnant smokers: a randomized controlled study. Obstet Gynecol 2000;96:967–71.
10. Chan B, Einarson A, Koren G. Effectiveness of bupropion for smoking cessation during pregnancy. J Addict Dis 2005;24:19–23.
11. Oncken CA, Kranzler HR. Pharmacotherapies to enhance smoking cessation during pregnancy. Drug Alcohol Rev 2003;22:191–202.
12. Melvin C, Gaffney C. Treating nicotine use and dependence of pregnant and parenting smokers: an update. Nicotine Tob Res 2004;6 suppl 2:S107–24.
14. Coleman T, Thornton J, Britton J, Lewis S, Watts K, Coughtrie MW, et al. Protocol for the smoking, nicotine and pregnancy (SNAP) trial: Double-blind, placebo-randomised, controlled trial of nicotine replacement therapy in pregnancy. BMC Health Serv Res 2007;7:2.
15. Schroeder DR, Ogburn PL Jr, Hurt RD, Croghan IT, Ramin KD, Offord KP, et al. Nicotine patch use in pregnant smokers: smoking abstinence and delivery outcomes. J Matern Fetal Neonatal Med 2002;11:100–7.
16. Ogburn PL Jr, Hurt RD, Croghan IT, Schroeder DR, Ramin KD, Offord KP, et al. Nicotine patch use in pregnant smokers: nicotine and cotinine levels and fetal effects. Am J Obstet Gynecol 1999;181:736–43.
17. Oncken CA, Hatsukami DK, Lupo VR, Lando HA, Gibeau LM, Hansen RJ. Effects of short-term use of nicotine gum in pregnant smokers. Clin Pharmacol Ther 1996;59:654–61.
18. Windsor R, Oncken C, Henningfield J, Hartmann K, Edwards N. Behavioral and pharmacological treatment methods for pregnant smokers: issues for clinical practice. J Am Med Womens Assoc 2000;55:304–10.
19. West R, McNeill A, Raw M. Smoking cessation guidelines for health professionals: an update. Health Education Authority. Thorax 2000;55:987–99.
20. National Health Service. National Institute for Clinical Excellence.Smoking cessation: bupropion and nicotine replacement therapy. Technology Appraisal Guidance No. 38. Available at: www.nice.org.uk/page.aspx?o=30631
. Retrieved October 24, 2007.
21. Report of the committee on safety of medicines working group on nicotine replacement therapy. London (UK): Medicines and Healthcare Products Regulatory Agency; 2005. p. 1–19.
22. Herbert R, Coleman T, Britton J. U.K. general practitioners’ beliefs, attitudes, and reported prescribing of nicotine replacement therapy in pregnancy. Nicotine Tob Res 2005;7:541–6.
23. Price JH, Jordan TR, Dake JA. Obstetricians and gynecologists’ perceptions and use of nicotine replacement therapy. J Community Health 2006;31:160–75.
24. Oncken CA, Pbert L, Ockene JK, Zapka J, Stoddard A. Nicotine replacement prescription practices of obstetric and pediatric clinicians. Obstet Gynecol 2000;96:261–5.
25. Hickner J, Cousineau A, Messimer S. Smoking cessation during pregnancy: strategies used by Michigan family physicians. J Am Board Fam Pract 1990;3:39–42.
26. Rigotti NA, Park ER, Regan S, Chang Y, Perry K, Loudin B, et al. Efficacy of telephone counseling for pregnant smokers: a randomized controlled trial. Obstet Gynecol 2006;108:83–92.
27. Heatherton TF, Kozlowski LT, Frecker RC, Fagerström KO. The Fagerström Test for Nicotine Dependence: a Revision of the Fagerström Tolerance Questionnaire. Br J Addict 1991;86:1119–27.
28. DiClemente CC, Prochaska JO, Fairhurst SK, Velicer WF, Velasquez MM, Rossi JS. The process of smoking cessation: an analysis of precontemplation, contemplation, and preparation stages of change. J Consult Clin Psychol 1991;59:295–304.
29. Ussher M, West R. Interest in nicotine replacement therapy among pregnant smokers. Tob Control 2003;12:108–9.
30. Griffiths AN, Woolley JL, Avasarala S, Roy M, Wiener JJ. Survey of antenatal women’s knowledge of maternal and fetal risks of tobacco smoking and acceptability of nicotine replacement products in pregnancy. J Obstet Gynaecol 2005;25:432–4.
31. Coleman T, Antoniak M, Britton J, Thornton J, Lewis S, Watts K. Recruiting pregnant smokers for a placebo-randomised controlled trial of nicotine replacement therapy. BMC Health Serv Res 2004;4:29.
32. Mullen PD, Pollak KI, Titus JP, Sockrider MM, Moy JG. Prenatal smoking cessation counseling by Texas obstetricians. Birth 1998;25:25–31.
33. Grimley DM, Bellis JM, Raczynski JM, Henning K. Smoking cessation counseling practices: a survey of Alabama obstetrician-gynecologists. South Med J 2001;94:297–303.
34. Chapin J, Root W. Improving obstetrician-gynecologist implementation of smoking cessation guidelines for pregnant women: an interim report of the American College of Obstetricians and Gynecologists. Nicotine Tob Res 2004;6 suppl 2:S253–7.
35. Castrucci BC, Culhane JF, Chung EK, Bennett I, McCollum KF. Smoking in pregnancy: patient and provider risk reduction behavior. J Public Health Manag Pract 2006;12:68–76.
36. Pullon S, Webster M, McLeod D, Benn C, Morgan S. Smoking cessation and nicotine replacement therapy in current primary maternity care. Aust Fam Physician 2004;33:94–6.