Amniotic fluid embolism is a rare but dangerous obstetric emergency that occurs during labor. It is caused by fetal tissue or other substances in the amniotic fluid entering the maternal circulatory system, causing pulmonary artery obstruction. This article will introduce in detail the causes and pathogenesis of amniotic fluid embolism. The main cause of amniotic fluid embolism is that foreign matter in fetal tissue or amniotic fluid enters the maternal circulatory system. These foreign bodies may be fetal skin cells, hair, clotting substances in the amniotic fluid, or amniotic fluid emboli. Amniotic fluid emboli refers to a mass composed of fetal villi, fetal skin, amniotic fluid pollutants, etc. in the amniotic fluid. They can trigger a series of physiological reactions after entering the maternal circulatory system. Once amniotic fluid emboli enter the maternal circulatory system, they travel through the venous system into the pulmonary arteries. In the pulmonary arteries, amniotic fluid emboli cause pulmonary vasoconstriction and inflammation, leading to pulmonary hypertension and right ventricular failure. At the same time, they will also activate the coagulation system, causing platelet aggregation and thrombosis, further aggravating the obstruction of pulmonary blood vessels. [The most complete and best sound quality in history] 32 sets of 100 must-listen late-pregnancy music for prenatal education for free. Amniotic fluid embolism can also cause systemic inflammatory response syndrome (SIRS). After amniotic fluid emboli enter the maternal circulatory system, they will release a series of inflammatory mediators, such as complement, tissue factor, prostaglandins, etc., leading to the occurrence of systemic inflammatory reactions. These inflammatory mediators activate leukocytes and platelets, leading to systemic intravascular coagulation (DIC) and multiple organ dysfunction syndrome (MODS). In addition to pulmonary artery obstruction caused by amniotic fluid emboli, bacteria in the amniotic fluid may also cause amniotic fluid embolism. During labor, if the cervix, uterine wall, or fetal membranes rupture, bacteria may enter the amniotic fluid. If these bacteria enter the maternal circulatory system, they can cause an infectious and inflammatory response, leading to pulmonary artery obstruction and systemic inflammation. Overall, the pathogenesis of amniotic fluid embolism is complex. It can be caused by amniotic fluid emboli or bacteria in the amniotic fluid, which can cause pulmonary artery obstruction and systemic inflammatory response after entering the maternal circulatory system. For pregnant women, it is very important to understand the causes and pathogenesis of amniotic fluid embolism, which can help early identification and timely treatment, and reduce the severity of the disease and mortality. Future research is needed to further explore the pathogenesis of amniotic fluid embolism in order to develop more effective prevention and treatment strategies.