Postpartum hemorrhage complicates approximately 5% of all deliveries. It is the second leading cause of maternal mortality in the United States, causing approximately 12% of all such deaths. All deliveries are associated with blood loss. Postpartum hemorrhage is defined as blood loss of at least 1000 cc or blood loss associated with symptoms of hypovolemia. Actual blood loss during the course of routine delivery may exceed 500 cc if carefully measured. Although the definition of postpartum hemorrhage remains unchanged, from a practical standpoint, postpartum hemorrhage is often understood as hemorrhage that persists beyond expectation. Early (primary) postpartum hemorrhage is defined as blood loss occurring in the first 24 h postpartum. Late (secondary) postpartum hemorrhage is defined as blood loss occurring between 24 h and 12 weeks’ postpartum.