Introduction: Second hand smoke exposure also known as passive smoking is a global health problem with profound impact on the expectant mother and her unborn baby. Still birth, the absence of life at birth, is a major obstetric problem. Ending preventable stillbirth is a global priority and hence assessing the causes is important. Association between second hand smoke exposure in pregnancy and stillbirth is hypothesized. But little is known about the role of second hand smoke and antepartum stillbirths in Kerala where the prevalence smoking among men is high.

Aims and Objectives: Primary Objective was to find the association between passive smoke exposure and the risk of still birth.

Methodology: This is a case control study conducted in the department of Obstetrics & Gynaecology, Govt. Medical College, Trivandrum, a tertiary care teaching hospital. 64 cases of sonologically confirmed antepartum still birth was compared with 128 live births (case control ratio 1: 2). Exposure to passive smoking was assessed by structured questionnaire and self report of passive smoking was quantified by estimating salivary continine which is a byproduct of nicotine using ELISA test. Salivary cotinine assay has a high sensitivity and specificity and is a non invasive test.

Results: The risk of antepartum stillbirth was 7 times higher among prenatal women exposed to second hand smoke as compared to those without exposure  (OR – 7.97, 95% CI – 4.01 to 15.84). There is a linear relationship between the duration and extent of exposure. Other risk factors are age > 30 years, lower socio economic status, increased BMI, gestational hypertension .On logistic regression analysis for confounding variables, second hand smoke exposure was found to have an independent association with stillbirth (P value < 0.001).

Conclusion: Based on our study we conclude that there is an association between prenatal second hand smoke exposure and risk of stillbirth.  This study is first of its kind in a state of Kerala, with a high rate of smoking among men .The results of this study shows that there is an urgent need for smoking cessation thereby avoiding passive smoke exposure to women and their unborn babies.

Keywords: second hand smoke, stillbirth, intrauterine death.

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Dr C. Nirmala

Department of Obstetrics and Gynecology, SAT Hospital, Govt. Medical College, Trivandrum