Amniotic fluid embolism occurs when some amniotic fluid (the fluid that surrounds the fetus in the uterus) that contains cells or tissue from the fetus enters the woman’s bloodstream and causes a serious reaction in the woman. This reaction can damage the lungs and heart and cause excessive bleeding.
Amniotic fluid embolism is very rare. It usually occurs during late pregnancy but may occur when an abortion is done during the 1st or 2nd trimester.
Risk is increased when
- Delivery is cesarean or forceps are used.
- The woman is older.
- There is more than one fetus in the uterus (multiple births).
- The placenta detaches too soon (placental abruption) or is in the wrong place (placenta previa).
- The woman has had an abdominal injury or a tear in the cervix.
- The uterus ruptures.
- There is too much fluid around the baby (polyhydramnios).
- Labor is artificially started (induced).
The fluid or tissue can cause a serious reaction in the woman. The reaction usually occurs during or shortly after labor and delivery. The woman may have a rapid heart rate, an irregular heart rhythm, low blood pressure, and difficulty breathing. She may stop breathing (respiratory failure), or her heart may stop (cardiac arrest). About 20% of women with amniotic fluid embolism die.
Disseminated intravascular coagulation is a common complication. In this disorder, small blood clots develop throughout the bloodstream, resulting in widespread bleeding with massive loss of blood. Emergency care is required.
Prompt diagnosis and treatment of amniotic fluid embolism are essential. Doctors diagnose this problem based on symptoms, particularly when a woman has the following three symptoms:
- Sudden difficulty breathing
- Low blood pressure
- Widespread, uncontrolled bleeding
Women may be given a transfusion of blood and blood components. Injection of a blood clotting factor (which helps blood clot) may be lifesaving. Women may require assistance with breathing or drugs to help the heart contract.
The baby may be delivered immediately using forceps or a vacuum extractor, or cesarean delivery may be done. Such a delivery does not appear to improve or worsen the woman's outcome. However, it may be lifesaving for the fetus if the fetus is old enough to survive outside the uterus.