A retrospective analysis was conducted on the outcomes of the pregnancies of 26 narcotic-addicted women who were enrolled in a methadone maintenance program. Of these women, 88% continued to use other drugs during their pregnancy, with opiates the most frequently used, and 56% of these women had urine toxicology screens positive for either heroin, cocaine, or benzodiazepines when they presented in labor. When these women were compared with a similar group of 37 pregnant polydrug users who were not in the methadone maintenance program and who delivered during the same 12-month period, there was no difference in the birth weights or in the infants' one- and five-minute Apgar scores. However, the women in the methadone maintenance program had more prenatal visits, more adequate prenatal care, and less anemia than the non-methadone maintenance program drug users. When these two drug-using groups were compared with a control group of pregnant women who delivered within the same time period, there was a significant difference in the birth weights of these two groups. This raises the question of the effectiveness of methadone maintenance programs in promoting fetal growth and well-being and in reducing polydrug use during pregnancy.