The use of prescription and over-the-counter medications and dietary supplements are common among women of reproductive age. For medications, little information about the teratogenic risks or safety is available, as pregnant women are traditionally excluded from clinical trials, and premarketing animal studies do not necessarily predict the effects of treatment in human pregnancy. Even less is typically known about the effects of dietary supplements on pregnancy outcomes, as they are not held to the same rigorous safety and efficacy standards as prescription medications. Congenital anomalies associated with medication use are potentially preventable, because they are linked with modifiable maternal exposures during the period of organogenesis. However, as women of reproductive age experience acute and chronic conditions that can result in adverse outcomes for the woman and her offspring, the benefits of use of a particular medication before or early in pregnancy may outweigh the risks. Resources and principles outlined in this article will aid healthcare providers in selecting appropriate medication regimens for women of reproductive age, particularly those with chronic health conditions, those who are planning a pregnancy, and those who may become pregnant.