Evaluation for placental abruption can include the following: Fetal heart monitoring CBC (complete blood count) Blood and Rh typing PT / PTT (prothrombin time / partial thromboplastin time) Serum fibrinogen and fibrin-split products (the most sensitive indicator) Pelvic ultrasonography Kleihauer-Betke test if the patient has Rh-negative blood—to calculate the dose of Rho (D) immune globulin needed The source of bleeding in placental abruption is maternal.