Placental Abruption
The medical term for separation of the placenta from the uterus is placental abruption 1, 2.
Definition and Clinical Context
Placental abruption is defined as the premature separation of the implanted placenta from the uterine decidua before delivery of the fetus 1, 2, 3.
This condition represents a complete or partial detachment of the placenta from the uterine wall while the fetus remains in the uterine cavity 4, 5.
The separation results from rupture of maternal decidual arteries, causing dissection at the decidual-placental interface 5.
Clinical Presentation
Classic manifestations include vaginal bleeding, abdominal pain, uterine contractions, and abnormal fetal heart rate patterns 1, 2.
The clinical picture varies widely—from asymptomatic cases diagnosed only by placental inspection after delivery to massive abruption causing fetal death and severe maternal morbidity 5.
Diagnosis is always clinical, as ultrasound has significant limitations in detecting placental abruption 6, 1.
Epidemiology
Placental abruption occurs in 0.4% to 1.2% of all pregnancies, with nearly half occurring at term gestations 1, 2.
The overall prevalence rate is approximately 9.6 per 1,000 births 3.
Severity Classification
Severe abruption is defined as abruption accompanied by maternal complications (disseminated intravascular coagulation, hypovolemic shock, blood transfusion, hysterectomy, renal failure), fetal complications (nonreassuring fetal status, intrauterine growth restriction, fetal death), or neonatal complications (neonatal death, preterm delivery, small for gestational age) 3.
Two-thirds of abruption cases qualify as severe based on these criteria 3.
Severe abruption carries a 4.29-fold increased risk of serious maternal complications compared to non-abruption cases 3.