羊水栓塞是一种罕见及未被完全了解的产科紧急症候。指在分娩过程中，羊水、胎儿细胞、胎发、胎粪、皮屑等物，透过子宫基底的胎盘进入母体血液循环而诱发母体之发炎反应。这作用引致心肺衰歇及凝血异常。此病最早在1941年被描述说明。在母体致死率的列表中羊水栓塞排列第五位。

羊水栓塞十分罕见（机会为8,000至80,000次分娩中出现一次，然于2007年研究给出的数字为20,464次分娩中出现一次）。大部份产科医生在整个执业生涯中可能从未经歴过。亦因此，这种状况的发生过程是很少被了解。一般认为，羊水及胎儿细胞进入母体肺循环（此可能使产妇心肺衰竭而亡）后将发生下列两个阶段。

An amniotic fluid embolism (AFE) is a rare childbirth (obstetric) emergency in which amniotic fluid, fetal cells, hair, or other debris enters the mother's blood stream via the placental bed of the uterus and triggers an allergic-like reaction. This reaction then results in cardiorespiratory (heart and lung) collapse and massive hemorrhaging (coagulopathy). It was first formally characterized in 1941. While it is rare (between 1 in 8000 and 1 in 80,000 deliveries), the high mortality makes it the fifth most common cause of maternal mortality in the world, in some estimates.