Thirty-four women who reported using cocaine during pregnancy were compared to 600 women who reported no cocaine use during pregnancy and none for the year prior to pregnancy. Subjects were participants in a prospective, longitudinal study of prenatal substance use. The sample consisted of young, predominantly single, low-income women attending a public prenatal clinic. Women were interviewed at the end of their first, second and third trimesters regarding cocaine, alcohol, marijuana, tobacco and other drug use. The majority of the cocaine users were light to moderate users who decreased their use during pregnancy. The cocaine group was more likely to be white and to use alcohol, marijuana, tobacco and other illicit drugs more heavily than the comparison group. The cocaine users had more previous fetal losses but did not differ on other obstetrical complications. Infant growth, morphology and behavior were not affected.