Abruptio placentae is defined as the premature separation of the placenta from the uterus. Patients with abruptio placentae typically present with bleeding, uterine contractions, and fetal distress. A significant cause of third-trimester bleeding associated with both fetal and maternal morbidity and mortality, abruptio placentae must be considered whenever bleeding is encountered in the second half of pregnancy.
Placental abruption seen after delivery.
Hemorrhage into the decidua basalis occurs as the placenta separates from the uterus. Vaginal bleeding usually follows, although the presence of a concealed hemorrhage in which the blood pools behind the placenta is possible.
If the bleeding continues, fetal and maternal distress may develop. Fetal and maternal death may occur if appropriate interventions are not undertaken. The primary cause of placental abruption is usually unknown, but multiple risk factors have been identified.1,2
The frequency of abruptio placentae in the United States is approximately 1%, and a severe abruption leading to fetal death occurs in 0.12% of pregnancies (1:830).
Maternal or fetal mortality or morbidity may occur.
If an abruption occurs, the risk of perinatal mortality is reported as 119 per 1,000 people in the United States, but this can depend on the extent of the abruption and the gestational age of the fetus.3 This rate is higher in patients with a significant smoking history. Fetal morbidity is caused by the insult of the abruption itself and by issues related to prematurity when early delivery is required to alleviate maternal or fetal distress.
Currently, placental abruption is responsible for approximately 6% of maternal deaths. Maternal and fetal complications include issues related to (1) cesarean delivery, (2) hemorrhage/coagulopathy, and (3) prematurity, described as follows:
* Cesarean delivery: Cesarean delivery is often necessary if the...