Are E-cigarettes associated with postpartum return to smoking? Secondary analyses of a UK pregnancy longitudinal cohort

Objectives Postpartum return to smoking (PPRS) is an important public health problem. E-cigarette (EC) use has increased in recent years, and in a contemporary UK pregnancy cohort, we investigated factors, including ECs use, associated with PPRS. Design Secondary analyses of a longitudinal cohort survey with questionnaires at baseline (8-26 weeks' gestation), late pregnancy (34-36 weeks) and 3 months after delivery. Setting 17 hospitals in England and Scotland in 2017. Participants The cohort recruited 750 women who were current or recent ex-smokers and/or EC users. A subgroup of women reported being abstinent from smoking in late pregnancy (n=162, 21.6%), and of these 137 (84.6%) completed the postpartum questionnaire and were included in analyses. Outcome measures Demographics, smoking behaviours and beliefs, views and experience of ECs and infant feeding. Results 35.8% (95% CI 28% to 44%) of women reported PPRS. EC use in pregnancy (adjusted OR 0.34, 95% CI 0.13 to 0.85) and breast feeding (adjusted OR 0.06, 95% CI 0.02 to 0.24) were inversely associated with PPRS, while household member smoking at 3 months post partum was positively associated with PPRS (adjusted OR 11.1, 95% CI 2.47 to 50.2). Conclusion EC use in pregnancy could influence PPRS. Further research is needed to confirm this and investigate whether ECs could be used to prevent PPRS.

Automated summary

This study aimed to investigate factors associated with postpartum return to smoking, including electronic cigarette (EC) use during pregnancy. The results showed that EC use during pregnancy and breastfeeding were negatively associated with postpartum return to smoking, while household member smoking at 3 months postpartum was positively associated. Further research is needed to confirm if ECs could be used for preventing postpartum return to smoking.