Passive maternal smoking and birthweight in a South Indian population

Abstract
Objective To determine the effects of passive maternal smoking on birthweight.Design Cohort of consecutive singleton live births.Setting Teaching hospital in South India.Subjects 994 infants and their mothers.Main outcome measure Birthweight.Results All the women were themselves non‐smokers; 520 (52%) were passive smokers while the remainder were not exposed to tobacco smoke. Infants born to passive smokers were on the average 55 g lighter than those born to non‐smokers. Passive smoking was associated with a decrease in birthweight of 63 g (95% CI 12–114 g) even after adjusting for other variables known to affect birthweight.