In 1976, the Department of Obstetrics and Gynecology at the Prentice Women's Hospital was invited to provide obstetric services to patients of the Drug Dependence Program administered by the Department of Psychiatry at Northwestern University Medical School. Patients were referred in the early stages of pregnancy if they agreed to participate in the Drug Dependence Program at the same time. Between April, 1976, and October, 1980, 58 women received prenatal, intrapartum and postpartum care. Forty-two of these patients had been abusers of opiates; 16 were polydrug abusers. The obstetric performance of these women was characterized by an absence of major problems. The mean weight of all infants delivered was 2,935 gm. There were no perinatal deaths. The individual weights, lengths, and head circumferences of the newborn infants were distributed in a relatively normal manner. Ninety percent of the infants were delivered at 37 weeks or more of gestation.