Abstract: Postpartum Hemorrhage is the leading cause of maternal death in China. We aimed to summarize the progress in the researches of antenatal, intrapartum and postpartum risk factors of Postpartum Hemorrhage, as well as the development of early warning assessment tools of Postpartum Hemorrhage. It is expected to provide information for further relevant clinical studies.

Key words: Postpartum Hemorrhage; risk factors; early warning assessment