Providers in prenatal care settings are well-positioned to help pregnant women with substance abuse problems take the first steps toward recovery. This study reports the results of the ANGELS Program, a program of enhanced prenatal care designed to reduce substance use among pregnant women. In a suburban office serving a broad range of pregnant women, certified nurse-midwives (CNMs) and on-site addictions counselors addressed substance abuse during prenatal care. This paper describes a cohort of 77 pregnant women who were identified as abusers of alcohol and/or other drugs at the start of pregnancy. According to a level of change rating assigned by the CNM at delivery, 51% of women were able to be largely abstinent during their pregnancy, 35% had reduced their use somewhat, and 14% had shown no change in use. Discriminant analysis techniques were used to learn what characteristics differentiated women in these three level of change groups. Baseline variables that differentiated the groups included severity of cocaine and cannabis use, psychosocial stressors, and initiation of prenatal care. Significant process variables included number of prenatal visits and contact with the addictions counselors. Clinical vignettes illustrate the differences among women in the three level of change groups. Implications of the results are discussed.