Prevalence of pre-gestational and gestational smoking and factors associated with smoking cessation during pregnancy, Brazil, 2011-2012

Gestational smoking is associated with various adverse maternal and fetal outcomes. Over the last three decades, despite considerable advances in tobacco control policy in Brazil, gestational smoking has caused a considerable number of fetal deaths and disabilities. The aim of this study is to estimate the prevalence of pre-gestational and gestational smoking and to identify the factors associated with smoking cessation up to the 20(th) gestational week. Methods: “Birth in Brazil” was a nationwide hospital-based study conducted from February 2011 to October 2012. Smoking prevalence and smoking cessation during pregnancy was estimated through face-to-face interviews with postpartum women during hospitalization for birth care. We performed multivariate logistic regression to verify the factors associated with smoking cessation up to the 5th month of pregnancy. Results: prevalence of pre-gestational smoking of 16.1% (CI 95% 15.3%-16.9%); prevalence of smoking any time during pregnancy of 9.6% (CI 95% 9.0%-10.3%); and prevalence of smoking cessation up to the 5th month of pregnancy of 56.7% (CI 95% 54.0%-59.4%). The factors associated with smoking cessation were residence in the North, Northeast, and Central-West of Brazil, having received at least one prenatal consultation (OR 3.51 CI 95% 1.85–6.67), more years of schooling (15 or more vs less than 7 years of schooling OR 5.54 CI 95% 2.97–10.34), living with a partner (OR 1.35 CI 95% 1.01–1.79), no children prior to the index pregnancy (OR 2.77 CI 95% 2.13–3.61), and absence of alcohol use (1.74 CI 95% 1.39–2.18) or of suspected alcohol abuse (OR 1.62 CI 95% 1.07–2.45). Conclusion: The estimated smoking rate during pregnancy in Brazil is still high and is associated with factors of increased maternal social vulnerability, which may contribute to the increased occurrence of unfavorable perinatal outcomes.