Preventing Placental Abruption

Placental abruption is the term for when part or all of the placenta separates unexpectedly from the uterus after the 20th week of pregnancy. Severe placental abruption is a major risk factor for stillbirth or preterm delivery.

It is also known as premature separation of the placenta, ablatio placentae, abruptio placentae or placenta abruption. The condition occurs in 1 percent of all pregnancies, most commonly in the third trimester.

Signs of placental abruption may include vaginal bleeding, tenderness or pain in the abdomen and frequent contractions. All vaginal bleeding in the second or third trimester should merit a call to a healthcare practitioner. Placental abruption does not always cause vaginal bleeding, however, so you should always call if you suspect you may be experiencing placental abruption. (Better to err on the side of caution when in doubt.)

Trauma to the abdomen in late pregnancy and infections in the uterus can cause placental abruption, but the condition can also occur without warning. Known risk factors for abruption of the placenta include:

• Smoking
• Using cocaine during pregnancy
• Being over 35 years of age
• Having a multiple pregnancy
• High blood pressure
• Having a blood clotting disorder like antiphospholipid syndrome
• Placental abruption in a previous pregnancy
• Premature rupture of membranes

In most cases of placental abruption, the placenta is only partially separated from the uterus rather than being entirely separate. When a larger percentage of the placenta is separated, the risk is higher than when the separation involves only a small part of the placenta. Odds of stillbirth go up drastically in placental abruption cases where more than 50 percent of the placenta is separated.

When a woman has symptoms of placental abruption, the healthcare practitioner will usually do a physical exam and an ultrasound. If doctors suspect serious abruption of the placenta, the usual treatment is to deliver the baby — by C-section in some cases.

Unfortunately, delivery does not always mean the baby survives. If a severe abruption happens before the baby is viable, such as before 24 weeks of pregnancy, doctors may not be able to save the baby at all. Mothers who have suffered a severe placental abruption may experience heavy blood loss, and babies who survive delivery may face complications from prematurity and oxygen deprivation.

When the placental abruption is less severe and is not posing an immediate risk to the mother or the baby, doctors may hospitalize the mother and keep her on bed rest with close monitoring. This can increase the odds that the baby will survive without serious health complications.

Sometimes the bleeding will stop and the woman will be able to return home for the remainder of the pregnancy, but some may need to remain in the hospital. If doctors expect the baby to be delivered between 24 and 34 weeks, they may prescribe steroids to help the baby's lungs mature more quickly to improve odds for survival.

Women who have had placental abruption in a past pregnancy may be considered high-risk in all future pregnancies, given that the condition recurs 10 percent of the time.