Review Question - QID 218511

This patient with a history of cocaine use who presents with sudden onset painful antepartum hemorrhage, a hypertonic uterus, and signs of fetal distress (late decelerations on fetal heart rate monitoring) most likely has placental abruption.

Placental abruption is partial or complete placental detachment before delivery of the fetus. Risk factors for placental abruption include maternal smoking, cocaine use, hypertensive disorders, and uterine structural abnormalities. The rupture of maternal vessels in the decidua basalis leads to bleeding into the decidual-placental interface, causing placental separation from the uterine wall. Signs and symptoms of placental abruption include painful vaginal bleeding in the third trimester, a gravid and hypertonic uterus, uterine tenderness, fetal distress, and vital signs consistent with severe bleeding. Diagnosis is clinical, though a transvaginal ultrasound can be used to help rule out other causes of vaginal bleeding. Treatment for placental abruption ranges from expectant management with continuous fetal monitoring to vaginal or cesarean delivery depending on fetal and maternal hemodynamic status.

Downes et al. review outcomes associated with placental abruption. The authors found that abruption was associated with an increased risk of cesarean delivery, postpartum hemorrhage, preterm birth, perinatal mortality, and cerebral palsy. The authors recommended further study on the optimal mode of delivery in the setting of abruption.

Incorrect Answers:
Answer 1: A cervical polyp is a growth on the cervical canal that is usually asymptomatic. Cervical polyps can be a cause of antenatal vaginal bleeding; however, it is generally painless and not associated with a hypertonic uterus.

Answer 3: Placenta previa is a condition in which the placenta overlies the neck of the uterus. Placenta previa can cause painless antepartum hemorrhage before rupture of membranes. Placenta previa is unlikely in this patient with a hypertonic uterus and painful vaginal bleeding.

Answer 4: Uterine rupture is a spontaneous tearing of the uterus that can occur during late pregnancy or labor and lead to the expulsion of the fetus. Uterine rupture usually presents with signs of hypotension with or without frank vaginal bleeding, a hypotonic uterus, sudden onset abdominal pain, and loss of fetal station. Uterine rupture is less likely in this patient without a history of prior cesarean deliveries and a firm uterus.

Answer 5: Vasa previa is a condition in which fetal vessels are located near the internal os of the cervix. Vasa previa can cause painless antepartum hemorrhage after rupture of membranes. Placenta previa is unlikely in this patient with painful vaginal bleeding.

Bullet Summary:
Placental abruption presents with vaginal bleeding, abdominal pain, and a hypertonic and tender uterus.