What is an Amniotic Fluid Embolism?

An amniotic fluid embolism is a very rare medical problem that can become life-threatening to a pregnant woman and her fetus. Complications occur when amniotic fluid or stray fetal cells escape the placenta and enter circulation in the mother’s bloodstream. Her immune system treats the foreign substance as a pathogen, releasing histamines and other chemicals that elicit an allergic response. As a result, the mother can suffer lung failure, heart failure, and brain damage that can ultimately lead to death without emergency medical care.

Doctors have not identified any clear causes, risk factors, or early warning signs of amniotic fluid embolism. Since the condition is so rare, there have not been many major research projects dedicated to uncovering potential causes. It appears that women over the age of thirty are at a slightly increased risk, as are patients who have allergies. An amniotic fluid embolism usually develops shortly before, during, or after labor, though it is possible to experience problems as early as the second trimester of pregnancy.

The immune system response to an amniotic fluid embolism is similar to what happens when a person has a severe allergy attack. A woman goes into anaphylactic shock as histamines cause inflammation of the airways, heart, and vital blood vessels. One of the first signs of an amniotic fluid embolism is extreme, sudden shortness of breath that may precede a collapsed lung. As the heart becomes more involved, dangerously low blood pressure and cardiac failure become likely. Heavy internal bleeding, seizures, coma, and fetal distress may also occur.

Immediate medical attention is needed whenever a patient shows symptoms of an amniotic fluid embolism. The main goal is to stabilize breathing and heart rate with oxygen therapy, cardiopulmonary resuscitation, medications, and intravenous fluids. Anti-inflammatory drugs and antihistamines may be given as well. Labor is induced right away via cesarean section to free the infant from the womb and treat him or her according to symptoms. A majority of babies are able to recover, though only about 20 to 40 percent of mothers survive even with expert care.

Women who are able to make it through the acute phase of an amniotic fluid embolism typically require long-term care and monitoring to combat various complications. Lung and heart problems may persist for several days or weeks, and any neurological damage suffered is often permanent. Survivors need to attend regular health checkups to make sure problems do not arise in the future.