Amniotic Fluid Embolism (AFE): A Rare Complication of Childbirth

Though access to the internet puts a wealth of childbirthing knowledge at our fingertips, rare complications are often overlooked in favor of addressing more commonly encountered obstacles. One such complication is Amniotic Fluid Embolism (AFE) — a severe allergic reaction that occurs in 1/40,000 deliveries in the United States (Cleveland Clinic, 2022). The infrequency of such complications, paired with a notable lack of research in the field of reproductive health, means that an increased importance falls on the individual awareness of pregnant women. Though researching complications like AFE can be understandably frightening, preparedness means giving yourself the option to discuss your fears with your healthcare provider and create a care plan. Doing so allows your caregivers, family, and most importantly, yourself the opportunity to be prepared to the best of your ability. 

What is Amniotic Fluid Embolism (AFE)?

Amniotic fluid is the nutrient-rich substance that surrounds a fetus during its development in the womb. It is common for some of this fluid to enter the mother’s bloodstream during, before, and after birth with no adverse effects. However, in 1 per every 40,000 births, the entrance of amniotic fluid into the bloodstream triggers a severe and life-threatening allergic reaction that requires immediate emergency intervention (Cleveland Clinic, 2022). AFE can also be triggered during an amniocentesis or a D&E procedure, though birth is the most common trigger for the condition (Amniotic Fluid Embolism Foundation, 2025).

Symptoms and Complications

AFE is an unpredictable complication of childbirth, with symptoms that can mimic those of uterine rupture, placental abruption, and eclampsia. Though symptoms arise rapidly, some common ones include difficulty breathing, fetal distress, agitation, and chills. Commonly resulting complications are heart and lung failure, stroke, brain damage, excessive bleeding from the vagina/C-section incision, or death (AFE Foundation, Cleveland Clinic). It is important to note that the symptoms and complications listed above are not all of those possible, and more information can be found on the cited websites. Complications to the fetus are dependent on when an AFE occurs — if a baby is delivered after AFE has already begun, the baby risks neurological impairment due to decreased oxygen intake (Cleveland Clinic, 2022). 

Risk Factors

As AFE is a rare condition with rapid onset, it is considerably difficult to predict what factors could lead to a higher risk of developing AFE. Current research names the following things as risk factors: geriatric pregnancy (ages 35 and above), expecting multiple children, preeclampsia/eclampsia, or the presence of too much amniotic fluid, also known as polyhydraminos (Kaur et. al). As always, this list is not extensive and the linked sources should be consulted for more detailed information. 

Diagnosis, Treatment, and Prognosis

The rapid progression of AFE means that physicians cannot rely on specific tests to reach a diagnosis. Diagnosis is made especially difficult by the fact that symptoms are often similar across other, equally severe medical complications. According to the Cleveland Clinic, AFE is classified in two stages: Phases I and II. Phase I is characterized by rapid respiratory failure and cardiac arrest. This is the phase with the lowest survival rate. Phase II (or the hemorrhagic phase) is characterized by massive bleeding from the uterus or location of a C-section incision. If AFE is identified, treatment consists of many things, possibly including immediate delivery of the baby, steroids to assist BP or heart rhythm, and/or a hysterectomy. As AFE is underresearched at this time, the tentative survival rate hovers around 40% (Cleveland Clinic, 2022). Long term effects for survivors appear to have both physical and psychological manifestations, such as permanent heart damage, kidney problems, or adverse effects to memory or word recall (Cleveland Clinic, 2022).