Assessment and management of bleeding in the first trimester of pregnancy.

Vaginal bleeding occurs in 15% to 25% of early pregnancies. While 50% of women who have vaginal bleeding in the first trimester of pregnancy will continue to have a viable pregnancy, the event creates significant anxiety for the woman and can be managed in a multitude of ways. The 3 main differential diagnoses associated with vaginal bleeding are spontaneous abortion, ectopic pregnancy, and gestational trophoblastic disease. This article reviews early pregnancy development, etiologies of vaginal bleeding in the first trimester, strategies for evaluation, and recognition and management of the main diagnostic considerations. Case study examples illustrating the complexity of the assessment and management of vaginal bleeding in early pregnancy are presented.