Tobacco use, exposure to second-hand smoke among pregnant women and their association with birth weight: A retrospective cohort study

Background: There is paucity of studies on prevalence of SHS among pregnant women and its association with low birth weight (LBW). Objectives: The study was designed to determine the proportion of tobacco use, exposure to second hand smoke among pregnant women and their association with LBW. Materials and Methods: A Retrospective cohort study was conducted from March-June 2017 among 1043 pregnant women admitted for delivery in the Department of Obstetrics and Gynecology, JIPMER. Socio-demographic and obstetric characteristics, tobacco use and exposure to SHS during pregnancy were assessed by interviews. Birth weight of the baby was also extracted. Data was analysed using STATA v12. Univariate analysis was used to assess the association of socio-demographic, obstetric characteristics and exposure to SHS with LBW. Results: Out of 1043 pregnant women, the mean age was 25 (±3.9) years. More than half (57.4%) of women were primigravida. The proportion of women exposed to SHS during pregnancy was 69.9% (95% CI: 67.0-72.6) among which 24% of the women belonged to family, where family members were smokers. Only four had ever used tobacco in the past. However, none used any form of tobacco during pregnancy. LBW was present in 21.4% of the babies. There was no association between exposure to SHS and LBW [PR:0.98 (95% CI:0.71-1.35)]. Conclusion: The study shows that there was no significant association between the SHS exposure of pregnant women and low birth weight.