The association of alcohol consumption with outcome of pregnancy.

Patterns of alcohol consumption were assessed in 12,440 pregnant women interviewed at the time of delivery. Only 92 women (0.7 per cent) reported drinking 14 or more drinks per week, with most consuming fewer than 21 drinks per week. In the crude data, alcohol intake of 14 or more drinks per week was associated with a variety of adverse pregnancy outcomes, including low birthweight, gestational age under 37 weeks, stillbirth, and placenta abruptio. After use of logistic regression to control for confounding by demographic characteristics, smoking, parity and obstetric history, only the association of placenta abruptio with alcohol consumption of 14 or more drinks per week remained statistically significant. With the exception of placenta abruptio, alcohol intake of fewer than 14 drinks per week was not associated with and increased risk of any adverse outcome. No association was seen with congenital malformations at any level of alcohol intake.