Cocaine abuse during pregnancy has been associated with increased perinatal morbidity and mortality regardless of the quantity or quality of prenatal care. In this study, we tested the hypothesis that among cocaine-abusing women delivering at the same institution, those receiving comprehensive prenatal care have better perinatal outcome than those receiving little or no prenatal care. Between January 1, 1984 and July 1, 1987, 120 pregnant women who abused cocaine received multidisciplinary prenatal care in the Perinatal Center for Chemical Dependence of Northwestern University (group 1). During this same period, we identified 21 cocaine-abusing parturients at our institution who were not enrolled in the Perinatal Center for Chemical Dependence and who received little or no prenatal care (group 2). Control subjects were selected from the general obstetric population for comparison. Data from these two groups were compared with each other and with matched control pregnancies. Group 2 pregnancies had lower mean gestational age at delivery, lower mean birth weight, and a higher incidence of preterm delivery than group 1 pregnancies. Furthermore, groups 1 and 2 were significantly different from control pregnancies for these parameters. We conclude that comprehensive prenatal care may improve outcome in pregnancies complicated by cocaine abuse; however, the perinatal morbidity associated with cocaine abuse cannot be eliminated solely by improved prenatal care.