This study examined whether prenatal care ameliorates the adverse effects of illicit drug use during pregnancy. We reviewed medical records of 336 women who delivered at the university hospital for results of urine drug screens, maternal history, infant outcome, and presence of prenatal care. Ninety-one women tested positive for illicit drugs, of whom 60 obtained prenatal care. We associated use of marijuana with increased risk of fetal distress; cocaine use with decreased birth weight, smaller head circumference, anemia, and meconium-stained amniotic fluid; and multiple drug use with decreased weight and meconium-stained fluid. Drug-using women who obtained prenatal care delivered infants of greater weight and with larger head circumferences than did those who obtained no care (p < .05). These results confirm the adverse effects of illicit drug use during pregnancy.