Postpartum hemorrhage (PPH) is an obstetric emergencythat can follow vaginal or cesarean delivery. It is a majorcause of shock, renal failure, acute respiratory distress syn-drome, coagulopathy and Sheehan’s syndrome. PPH is oneof the top Wve causes of maternal mortality in both high-income and low-income countries, with a much lower abso-lute risk of death in the former [1].The true incidence of PPH is unknown, but a reasonableestimate is 1–5% of deliveries. Figures vary according tothe criteria used to deWne the disorder [1]. The most com-mon deWnition of PPH is an estimated blood loss of 500 mlafter vaginal birth or 1,000 ml after cesarean delivery [2],yet accurate measurement of blood loss is rarely possible orpracticable. PPH can also be de Wned as 10% change in hae-matocrit from admission assessment to postpartum data, orthe need to administer a transfusion of red blood cells [3].PPH is classiWed as primary or secondary. Primary PPHoccurs within 24 h after delivery, and secondary PPHoccurs 24 h to 6 weeks after delivery.Bleeding after delivery is controlled by a combination ofcontraction of the myometrium, which constricts the bloodvessels supplying the placental bed, and local decidual hae-mostatic factors, including tissue factor, type-1 plasmino-gen activator inhibitor and systemic coagulation factors [ 4].DeWcient contraction of the myometrium is manifestedclinically as uterine atony. Defective decidual homeostasisis associated with inadequate decidualization or bleedingdiatheses.