Placental Abruption

(Abruptio Placentae): Placental abruption is the premature detachment of a normally positioned placenta from the wall of the uterus. The placenta may detach incompletely (sometimes just 10 to 20%) or completely. The cause is unknown. Detachment of the placenta occurs in 0.4 to 3.5% of all deliveries. This complication is more common among women who have high blood pressure (including preeclampsia) and among women who use cocaine.

The uterus bleeds from the site where the placenta was attached. The blood may pass through the cervix and out the vagina as an external hemorrhage, or it may be trapped behind the placenta as a concealed hemorrhage. Symptoms depend on the degree of detachment and the amount of blood lost (which may be massive). Symptoms may include sudden continuous or crampy abdominal pain, tenderness when the abdomen is pressed, and shock. Premature detachment of the placenta can lead to widespread clotting inside the blood vessels (disseminated intravascular coagulation), kidney failure, and bleeding into the walls of the uterus, especially in pregnant women who also have preeclampsia. When the placenta detaches, the supply of oxygen and nutrients to the fetus may be reduced.

Doctors suspect premature detachment of the placenta on the basis of symptoms. Ultrasonography can confirm the diagnosis.

Women with premature detachment of the placenta are hospitalized. The usual treatment is bed rest. If symptoms lessen, women are encouraged to walk and may be discharged from the hospital. If bleeding continues or worsens (suggesting that the fetus is not getting enough oxygen) or if the pregnancy is near term, an early delivery is often best for the woman and the baby. If vaginal delivery is not possible, a cesarean section is performed

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