Demographic factors and patterns of substance use among women who did not consume alcohol during pregnancy were compared to women who did consume alcohol during pregnancy. One-hundred seventy-seven Northern Plains Indian women who received prenatal care at an urban clinic in a rural state were screened for substance use as part of the validation study with a self-administered questionnaire. Women who drank during pregnancy were more likely to be single and have less education than women who did not drink. While most of the women in the study had available transportation resources, the women who drank during pregnancy were less likely to have transportation than the women who did not drink. Women who drank during pregnancy consumed more alcohol more frequently before pregnancy than did women who drank before but not during pregnancy. Compared to women who did not drink during pregnancy, women who drank during pregnancy were more likely to smoke cigarettes and use illicit drugs, to have parents who drank, to feel they drank the same or more than other pregnant women, or to have experienced more relationship breakups and physical and emotional abuse. Prenatal patients who drink alcohol during pregnancy need more intensive counseling regarding their multiple risk behaviors.