产后出血是指胎儿娩出24h内失血量超过500ml,为分娩期的严重并发症之一,居我国孕产妇死亡原因的首位,发病率占分娩总数的2%~3%[1]。引起产后出血的原因主要有子宫收缩乏力、胎盘因素、软产道裂伤和凝血功能障碍等,其中以子宫收缩乏力最为常见,占70%~90%,其他因素导致的产后出血 Postpartum hemorrhage refers to the amount of blood loss of more than 500ml delivered by the fetus within 24h, which is one of the serious complications of childbirth. It ranks first in the cause of maternal death in China, accounting for 2% -3% of the total number of deliveries. The main causes of postpartum hemorrhage uterine atony, placental factors, soft birth canal laceration and coagulation disorders, etc., of which the most common uterine atony, accounting for 70% to 90%, other factors lead to postpartum hemorrhage