A substance use screening instrument was used to select persons into two risk categories for drinking during pregnancy. About one-fourth (23.8%) of the survey participants were classified as high-risk women and the others were classified as low risk for drinking when pregnant. The participants (N=4676) for the study were sampled from four states (Montana, Minnesota, South Dakota, and North Dakota) that are a part of the Four-State Fetal Alcohol Syndrome (FAS) Consortium. Clinic sites for the administration of the prenatal screening instrument were selected in each state, based on geographic and known population characteristics. Univariate and multivariate statistical procedures were used to determine factors predictive of alcohol use. The purpose of the study was to assess risk factors for alcohol use in pregnant women. Women at high risk for alcohol use when pregnant tended to be younger, less educated, single, and unemployed. Demographic factors that were protective of drinking when pregnant were being married and full-time housewife status. Other variables associated with high-risk status for maternal alcohol use were past sexual abuse, current or past physical abuse, using tobacco, using other drugs, living with substance users, and having mates who were substance users. Other contributing factors for high-risk classification included feeling sad, believing that drinking any amount of alcohol while pregnant was acceptable, and being able to hold four or more drinks. Intervention programs that ameliorate risk factors and enhance protective attributes of high-risk pregnant women are needed.