Amniotic Fluid Embolism

Amniotic fluid embolism (AFE) is a rare complication of pregnancy often resulting in catastrophic maternal and fetal outcomes. Given the rarity of this condition, there is a wide variation in reported incidence of amniotic fluid embolism. The pathophysiology of AFE is not completely understood. It is thought to be the result of a breach of the maternal-fetal barrier resulting in an abnormal maternal proinflammatory response. AFE presents as a sudden onset of hypoxia, hypotension, and coagulopathy during labor and delivery or in the immediate postpartum period. Abnormalities in the fetal heart tracing are almost always present. Risk factors often include advanced maternal age, induction of labor, cesarean delivery, operative vaginal delivery, placenta previa, and placental abruption. The diagnosis of amniotic fluid embolism is made based on clinical presentation. There are no laboratory tests that confirm the diagnosis of AFE; however, serum tryptase levels, complement levels, zinc coproporphyrin, and serum sialyl Tn (STn) may support the diagnosis. Management of women with AES is supportive and most often requires admission to an intensive care unit. Although maternal morbidity and mortality remain high, advances in medical technology and improvements in obstetrical critical care and early diagnosis of AFE have improved outcomes