Results: The main causes were retained placenta and membranes,endometritis and decidualitis,infection,dehiscence and hemorrhage of caesarean incision,sub involution of uterus.

• 结果:主要病因依次为胎盘、胎膜残留,子宫内膜炎和(或)蜕膜炎,剖宫产术的子宫切口感染、裂开出血以及子宫复旧不良等。