Bleeding per vagina may occur at any point during the course of pregnancy and always warrants careful attention to identification and management of the underlying etiology. Bleeding that occurs late in pregnancy (generally within the third trimester) is covered in Chap. 10 . Bleeding that occurs early in pregnancy (generally within the first trimester) is of particular concern because of concerns with pregnancy viability and possible ectopic pregnancy with its associated morbidity and mortality. A careful review of common etiologies combined with a careful history, directed physical examination, and selected diagnostic studies will allow the provider to identify the underlying cause and initiate appropriate management in a timely manner.