Placenta abruptio is the separation of the placenta (the organ that nourishes the fetus) from its attachment to the uterus wall before the baby is delivered.
Premature separation of placenta; Ablatio placentae; Abruptio placentae; Placental abruption
Causes, incidence, and risk factors
The exact cause of a placental abruption may be hard to determine.
Direct causes are rare, but include:
- Injury to the belly area (abdomen) from a fall, hit to the abdomen, or automobile accident
- Sudden loss of uterine volume (can occur with rapid loss of amniotic fluid or after a first twin is delivered)
Risk factors include:
- Blood clotting disorders (thrombophilias)
- Cigarette smoking
- Cocaine use
- Drinking more than 14 alcoholic drinks per week during pregnancy
- High blood pressure during pregnancy (about half of placental abruptions that lead to the baby's death are linked to high blood pressure)
- History of placenta abruptio
- Increased uterine distention (may occur with multiple pregnancies or very large volume of amniotic fluid)
- Large number of past deliveries
- Older mother
- Premature rupture of membranes (the bag of water breaks before 37 weeks into the pregnancy)
- Uterine fibroids
Placental abruption, which includes any amount of placental separation before delivery, occurs in about 1 out of 150 deliveries. The severe form, which can cause the baby to die, occurs only in about 1 out of 800 to 1,600 deliveries.
- Abdominal pain
- Back pain
- Frequent uterine contractions
- Uterine contractions with no relaxation in between
- Vaginal bleeding
Signs and tests
Tests may include:
- Abdominal ultrasound
- Complete blood count
- Fetal monitoring
- Fibrinogen level
- Partial thromboplastin time
- Pelvic exam
- Platelet count
- Prothrombin time
- Vaginal ultrasound
Treatment may include fluids through a vein (IV) and blood transfusions. The mother will be carefully monitored for symptoms of shock. The unborn baby will be watched for signs of distress, which includes an abnormal heart rate.
An emergency cesarean section may be needed. If the baby is very premature and there is only a small placental separation, the mother may be kept in the hospital for close observation. She may be released after several days if the condition does not get worse and any bleeding stops.
If the fetus is developed enough, vaginal delivery may be done if it is safe for the mother and child. Otherwise, a cesarean section will be done.
The mother does not usually die of this condition. But any of the following increases the risk of death for both the mother and baby:
- Closed cervix
- Delayed diagnosis and treatment of placental abruption
- Excessive blood loss, leading to shock
- Hidden (concealed) uterine bleeding in pregnancy
- No labor
Fetal distress occurs early in the condition in about half of all cases. Infants who live have a 40-50% chance of complications, which range from mild to severe.
Excess blood loss can lead to shock and possible death of the mother or baby. If bleeding occurs after the delivery and blood loss cannot be controlled in other ways, the mother may need a hysterectomy (removal of the uterus).
Calling your health care provider
Call your health care provider right away if:
- You are in an auto accident, even if the accident is minor.
- You fall and hit your abdomen.
- You have vaginal bleeding during pregnancy.
See your health care provider right away, call your local emergency number (such as 911), or go to the emergency room if you have vaginal bleeding and severe abdominal pain or contractions during your pregnancy. Placental abruption can quickly become an emergency condition that threatens the life of both the mother and baby.
Do not drink any alcohol, such as beer and wine. Do not smoke or use recreational drugs during pregnancy. Get early and regular prenatal care.
Recognizing and managing conditions in the mother such as diabetes and high blood pressure also decrease the risk of placental abruption.
Francois KE, Foley MR. Antepartum and postpartum hemorrhage. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics - Normal and Problem Pregnancies. 6th ed. Philadelphia, PA: Elsevier Saunders; 2007:chap 19.
Houry DE, Salhi BA. Acute complications of pregnancy. In: Marx J, Hockberger RS, Walls RM, et al, eds. Rosenâ€™s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, PA: Elsevier Mosby; 2009:chap 176.
Cunningham FG, Leveno KL, Bloom SL, et al. Obstetrical hemorrhage. In: Cunningham FG, Leveno KL, Bloom SL, et al., eds. Williams Obstetrics. 23rd ed. New York, NY: McGraw-Hill; 2010:chap 35.