When approaching a patient with congenital malformations, it is important to take a detailed family history and pregnancy history and perform a detailed physical examination observing associated abnormal features. Pregnancy history should include any illnesses, environmental exposures, medications, and use of illicit drugs as well as any complications of chronic medical illnesses (e.g., gestational diabetes). Taking note of both major structural defects and minor dysmorphic features may help to establish a unifying diagnosis. Birth defects can be isolated or can occur as part of a set of...