早产是指在妊娠足月(满37周)前发动分娩而将胎儿娩出。每年全世界大约有1300万早产儿出生,大部分出生在发展中国家。早产儿存活率低、各种并发症发生率高,其救治及并发症的长期治疗大大加重了发展中国家的医疗和经济负担。因此,对于分娩动因与早产的研究目前受到世界围生界的广 Premature delivery refers to the delivery of the fetus before the full term of pregnancy (37 weeks). Approximately 13 million premature babies are born each year in the world, most of them born in developing countries. Premature babies have low survival rates and high rates of complications, and long-term treatment of their complications and complications have exacerbated the medical and financial burden in developing countries. Therefore, the study of childbirth mothers and premature birth is currently widely accepted by the world’s perinatal community