Attitudes toward exercise during pregnancy have changed dramatically over the past 20 years. Recent studies show that, in most cases, exercise is safe for both the mother and fetus during pregnancy, and support the recommendation to initiate or continue exercise in most pregnancies. This report discusses the rationale behind the changes, and offers educational tools that may be employed to initiate behavioral change. We also propose exercise prescriptions for pregnant women who are sedentary, physically active, and competitive athletes. Armed with this information, the practitioner will be better equipped to counsel patients and incorporate a discussion on physical activity into prenatal visits.