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.
Signs and tests
Tests may include:
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.
If the fetus is developed enough, vaginal delivery may be done if it is safe for the mother and child. Otherwise, a cesarean section may be done.
The mother does not usually die from this condition. However, all of the following increase the risk for death in 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 may lead to shock and possible death in 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 if you are in an auto accident, even if the accident is minor.
Call your doctor right away if you have 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 are pregnant and 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.
Avoid drinking, smoking, or using 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. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2007:chap 18.
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: Mosby Elsevier; 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.
Reviewed By: Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.