Cigarette Smoking Reduction in Pregnant Women with Opioid Use Disorder

Objectives: Nearly 95% of women with opioid use disorder continue to smoke cigarettes during pregnancy. Despite this prevalence and the well documented adverse effects of smoking on birth outcomes, cigarette smoking is underaddressed in this population. This study examines factors associated with successful smoking reduction among pregnant women with opioid use disorder and the impact of smoking reduction on maternal and birth outcomes. Methods: This study is a secondary data analysis of maternal smoking reduction and infant birth outcomes among pregnant women with opioid use disorder (N=118), enrolled in a randomized controlled trial of a contingency management intervention in which escalating monetary vouchers were provided to women who met escalating smoking-reduction targets. Results: Participants' ability to meet higher smoking reduction targets was associated with less cocaine use at baseline (P=0.022), higher carbon monoxide levels at baseline (P=0.039), fewer prior quit attempts (P=0.016), participation in the contingency management intervention, and greater adherence with the parent trial protocol. Some clinically relevant associations were found between smoking reduction and birth outcomes, including birth weight, spontaneous abortions, and neonatal abstinence syndrome treatment, but these differences did not reach statistical significance. Conclusions: Contingency management promotes smoking reduction, but other factors may be associated with such reduction, including baseline smoking and illicit drug use, prior quit attempts, and willingness to participate in the incentives program. Clinicians caring for pregnant women with opioid use disorder may see greater smoking behavior change if they first encourage smoking reduction before recommending smoking cessation. Future research is needed to determine the level of smoking reduction needed to positively impact birth outcomes.