An obstetric hemorrhage may occur before or after delivery, but more than 80% of cases occur postpartum. Worldwide, a massive obstetric hemorrhage, resulting from the failure of normal obstetrical, surgical and/or systemic hemostasis, is responsible for 25% of the estimated 358,000 maternal deaths each year. Most women will not have identifiable risk factors. Nonetheless, primary prevention of a postpartum hemorrhage (PPH) begins with an assessment of identifiable risk factors. Women identified as being at high risk of a PPH should be delivered in a center with access to adequately trained staff and an onsite blood bank. A critical feature of a massive hemorrhage in obstetrics is the development of disseminated intravascular coagulation (DIC), which, in contrast to DIC that develops with hemorrhage from surgery or trauma, is frequently an early feature. Data from clinical trials to guide management of transfusion in PPH are lacking. There are likely to be similarities in the management of transfusion in severe PPH to that of major bleeding in other clinical situations, but the pathophysiological processes that contribute to a massive PPH may necessitate different transfusion strategies such as the ratio of red blood cells to plasma components, in particular fibrinogen. Caution should be exercised when considering the appropriate place for recombinant activated factor VII (rFVIIa) in the management of a major PPH. An early hysterectomy is recommended for severe bleeding as a result of placenta accreta or uterine rupture. However, in women with uterine atony who have ongoing bleeding in spite of an adequate transfusion, it may be reasonable to consider a trial of rFVIIa before a hysterectomy.