First-trimester drug use and congenital disorders.

The authors determined the prevalence of certain major congenital disorders among live-born infants of 6509 mothers in a prepaid health plan for the 30-month period of January 1, 1980 through June 30, 1982 who used a wide variety of drugs during the first trimester of pregnancy. The results were similar to those obtained in this population in a prior 30-month study. No strong associations between any of the commonly used drugs and the congenital disorders studied were present.