RT Book, Section A1 Bellil, Lisa A2 Freeman, Brian S. A2 Berger, Jeffrey S. SR Print(0) ID 1135743281 T1 Postpartum Hemorrhage T2 Anesthesiology Core Review: Part Two Advanced Exam YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9781259641770 LK accessanesthesiology.mhmedical.com/content.aspx?aid=1135743281 RD 2023/10/04 AB Postpartum hemorrhage is the most common cause of clinically significant blood loss in obstetrics practice and is the leading cause of maternal and fetal morbidity and mortality globally. It is defined as any bleeding occurring within 6 weeks following delivery. However, serious blood loss most frequently occurs during the immediate postpartum period or within 1–2 hours following delivery. Blood loss of greater than 500 mL for vaginal delivery or greater than 1000 mL for caesarian section are values commonly included in guidelines for the diagnosis of postpartum hemorrhage. A decrease of 10% of hematocrit from admission to the postpartum period can also signify significant blood loss. It should be noted that many studies have shown postpartum blood loss to be significantly underestimated by clinicians.