Amniotic Fluid Embolism

What is an Amniotic Fluid Embolism?

Amniotic fluid embolism develops when the amniotic fluid that normally surrounds a baby within the womb during pregnancy ends up entering the mother’s bloodstream. It can also occur when other fetal material, including fetal cells, enter the mother’s bloodstream during pregnancy.

Although rare, this is a serious condition. It is more likely to occur either during the delivery of a baby or immediately following delivery. Prompt treatment will be necessary to prevent complications that could be life-threatening.

Risk factors for amniotic fluid embolism include: advanced maternal age, cesarean delivery, medically induced labor, and placenta problems.

What are the Symptoms of an Amniotic Fluid Embolism?

Symptoms of amniotic fluid embolism will develop rapidly and suddenly.

Symptoms include

  • Pulmonary edema, which is excessive fluid within the lungs
  • Shortness of breath or low blood pressure that occurs suddenly
  • Cardiovascular collapse, which is the sudden inability of the heart to pump blood effectively
  • Altered mental states, such as anxiety
  • A rapid heart rate or a disturbance in the heart rate’s rhythm
  • Chills
  • Seizures
  • Disseminated intravascular coagulopathy, which involves blood clotting problems that are life-threatening
  • Coma
  • Abnormalities in fetal heart rate, or fetal distress that could include a slow heart rate
  • Bleeding from intravenous or incision sites, or from the uterus

Amniotic Fluid Embolism Causes

The actual cause of this condition is not fully understood. One theory as to what causes Amniotic Fluid Embolism (also known as AFE) is some sort of traumatic breakdown of the placental barrier. This trauma may then cause a response in the mother’s circulatory system as fetal antigens enter it. That response may include abnormal clotting or excessive bleeding (coagulopathy), which then could travel to the mother’s vital organs, potentially leading to catastrophic organ failure in the mother and less often, in the infant. Up to 50% of women who develop this condition die from complications caused by it (in developed countries), and up to 20% of all maternal deaths in these countries can be linked to AFE.

How is an Amniotic Fluid Embolism Treated?

Rapid treatment is necessary in order to resolve low blood pressure and low blood oxygen levels associated with amniotic fluid embolism.

Emergency treatment could include the insertion of a breathing tube for more oxygen, the administration of medications to support or improve heart function and decrease any pressure caused by the fluid in the lungs and heart, and the placement of a catheter to provide medications or fluids. Transfusions might also be necessary to combat uncontrollable bleeding.

Amniotic Fluid Embolism Prevention

Prevention of Amniotic Fluid Embolism is difficult since so little is understood about its causes. However, by linking prevention to some of the common conditions that seem to lead to this condition, prevention may be possible. In studies (often post mortem) of women who have had AFE, there are a few prenatal conditions that seem to be present often. Conditions such as preeclampsia, hypoxia, hypotension, any sort of placental abnormality, caesarean section births, polyhydramnios (excessive amniotic fluid) and pregnancy over the age of 35 are all conditions that in limited research seem more likely to result in AFE in the mother.

Controlling those variables in these conditions and early diagnosis of these conditions so they can be carefully monitored may prevent the ultimate breakdown of the placental barrier and the inflammatory response that it can cause in the mother. Other than vigilant prenatal care, careful examinations and diagnosis of the health of the mother, particularly if she is over 35 or has had an AFE episode previously, there is really no effective protocol to prevent Amniotic Fluid Embolism from occurring.

Last Reviewed:
September 12, 2016
Last Updated:
November 07, 2017