Patterns of alcohol and cigarette use in pregnancy.

Maternal smoking and drinking have been implicated as factors in the adverse outcome of pregnancies. This California study of over 12,000 women demonstrates that a large proportion of them smoke or drink during pregnancy. Drinking habits appear to be associated with age, ethnicity, martial status, income, education, church attendance, and prenatal care, but not with gestational age, breast-feeding, or self-reported health. Smoking shows associations with income and education. Drinking and smoking are closely interrelated, showing strikingly parallel associations with such factors as use of caffeine or illicit drugs. Subgroups of pregnant women who exhibit difference drinking habits were found not comparable on certain other characteristics which potentially influence the health of neonates. The importance is reemphasized of utilizing large populations, adjusting for confounding variables, and paying particular attention to smoking habits. Forthcoming multivariate analyses of the data set should disentangle effects of the confounding variables.