Prenatal smoking and birth outcomes among Mississippi residents.

In this study we examined trends within Mississippi in prenatal smoking and in the effects of such smoking on birthweight, preterm delivery, and infant mortality. The study was a retrospective cohort analysis of 120,429 singleton births in 1995-1997. We found that even though prenatal smoking is decreasing overall, it is increasing among young pregnant women aged 15-19 years. The primary effect of prenatal smoking was to lower birthweight; correspondingly, the principal effect of smoking on infant death appeared to be this decreasing of birthweight. In addition, infants of mothers who smoked during pregnancy were two and one-half times as likely to die from SIDS as were infants whose mothers did not smoke. These data demonstrate the importance of strategies such as training in smoking cessation for providers of prenatal care in Mississippi and provide a foundation for future evaluations of current aggressive anti-tobacco campaigns in the state.