Substance use disorders (SUDs) in pregnancy are becoming increasingly prevalent. Our study aimed to measure the effect of a teaching module on alcohol, tobacco, and drug use on the attitude of second year medical students toward pregnant women with SUDs. A questionnaire was administered to 84 medical students before a 5-week systems block on human reproduction, which included specific learning events related to SUDs. The questionnaire was readministered at the completion of the block. Pre- and postintervention scores were compared. Students showed significant improvement (p < .05, reliability coefficient 0.90) in their level of comfort in dealing with womenwith SUD in pregnancy. Other positive trends relating to attitudes toward drug- and alcohol-dependent women during pregnancy were also identified. SUD teaching interventions among medical students can improve their comfort level and attitude toward pregnant women with SUDs. This supports the current initiative of Project CREATE (Curriculum Renewal and Evaluation of Addiction Training and Education) to implement a comprehensive undergraduate SUD teaching program in Canadian medical schools.