About half of women smokers stop smoking during pregnancy, and that means about 13% of women in the United States continue to smoke while pregnant.  In addition, about half of the women who manage to stop smoking during pregnancy relapse during the postpartum period.  While smoking is a potential problem for all women, rates of tobacco use are higher among who suffer from depression.  Rates of smoking during pregnancy are particularly high (greater than 50%) among pregnant women with schizophrenia.

Because smoking clearly carries significant risk for the pregnant mother and her child, the American College of Obstetricians and Gynecologists recently issued a report recommending increased attention focus to smoking cessation during pregnancy and the postpartum period.  Although women who are pregnant or planning to conceive are highly motivated with regard to smoking cessation, smoking cessation is difficult and many women relapse.  Furthermore, in pregnant and postpartum women, it is not clear which smoking cessation strategies are most effective.  

Bupropion is an antidepressant (marketed as Wellbutrin) which has also been used to promote smoking cessation (marketed as Zyban).  Researchers recently published a pilot study evaluating the efficacy of bupropion sustained release for smoking cessation during pregnancy.

This study is quite unusual in that it was a randomized, prospective, double-blind, placebo-controlled trial, where pregnant women who smoked daily were recruited.  All women received individualized behavior counseling and were randomly assigned to 12 weeks of twice-a-day treatment with 150 mg bupropion sustained release (n=30) or placebo (n=35).

After controlling for maternal age and race, the researchers found that bupropion SR reduced cigarette cravings (1.5±1.1 vs 2.1±1.2, P=0.02) and total nicotine withdrawal symptoms (3.8±4.3 vs 5.4±5.1, P=0.028) during the treatment period. Of greater clinical significance is the fact that bupropion SR reduced tobacco exposure, as measured by levels of carbon monoxide in exhaled air (7.4±6.4 vs. 9.1±5.8, P=0.053) and concentrations of cotinine (a metabolite of nicotine) in urine (348±384 ng/mL vs. 831±727 ng/mL, P=0.007).  However, treatment with bupropion SR did not increase rates of abstinence.   Bupropion did not significantly reduce the 7-day point prevalence abstinence rate, compared to placebo (17% vs 3%, respectively), nor did it reduce abstinence at the end of pregnancy (10% vs 3%, respectively).

This study indicates that smoking cessation counseling combined with 150 mg or bupropion SR increased smoking cessation rates and reduced cravings and withdrawal symptoms during the treatment period.  What is discouraging is that, despite treatment with therapy and medication, 81% of the women were still smoking during pregnancy.  

Some Other Thoughts About This Study

Perhaps more interesting than the actual findings is the fact that this was a randomized controlled trial of a psychotropic medication carried out in pregnant women.  Because of ethical and legal concerns, clinical trials in pregnant women are rarely conducted.  When a new medication is introduced, information on its reproductive safety comes from animal studies which may or may not give an accurate reflection of reproductive safety.   It may take many years, or even decades, before sufficient observational data in humans are available to guide clinical treatment decisions.  Nor do we typically have the opportunity to determine if the medication works the same way in pregnant patients as it does in non-pregnant patients.

Ruta Nonacs, MD PhD

Nanovskaya TN, Oncken C, Fokina VM, Feinn RS, Clark SM, West H, Jain SK, Ahmed MS, Hankins GD.  Bupropion sustained release for pregnant smokers: a randomized, placebo-controlled trial.  Am J Obstet Gynecol. 2016 Nov 25.