Monitoring for teratogenic signals: pregnancy registries and surveillance methods.

Pregnant women should have access to medications that have been adequately studied for use to facilitate evidence-based risk-benefit discussions with their health care providers. Pregnant women experience acute medical emergencies, have existing conditions that require continued medical treatment or may develop pregnancy-induced conditions, making drug use during pregnancy unavoidable. Drug labeling is the primary source of information about a drug's use. The safety and efficacy data found in the label is derived from well-controlled clinical trials conducted prior to a drug's approval. However, pregnant women are rarely enrolled in clinical trials unless a product is specifically indicated for a pregnancy-related condition. Consequently, information regarding a product's use during pregnancy is usually collected postapproval. Current data collection tools include pregnancy exposure registries, retrospective cohort studies, pregnancy surveillance programs, case-control studies, spontaneous reports of adverse events and case reports. Each tool has strengths and limitations in its ability to detect teratogenic signals. Combinations of different sources of data are necessary to acquire the most complete picture of potential teratogenic risk, as no single method can capture all desired data to help pregnant patients and women of child bearing potential make appropriate risk benefits decisions along with their health care providers.