Unexplained prelabor uterine rupture in a term primigravida

Uterine rupture is a catastrophic obstetric complication. The main risk factor is a scarred uterus, usually secondary to a previous cesarean delivery. Uterine rupture in a primigravid woman is a very rare event.

A 33-year-old primigravida presented at term with severe abdominal pain, signs of hemodynamic instability, and fetal bradycardia. She was not in labor, and the fetal heart tones disappeared before a cesarean could be performed. After a failed attempt at induction, exploratory laparotomy was performed for worsening maternal hemodynamic status. A complete rupture of the posterior uterine wall was found with a well-grown fetus free in the abdominal cavity. The uterus was repaired in two layers, and the patient did well postoperatively.

We report the rare occurrence of a spontaneous uterine rupture in a nonlaboring primigravid with no known risk factors. The differential diagnosis of this presentation includes concealed placental abruption, subhepatic hematoma with or without liver rupture, splenic rupture, rupture of the broad ligament, and rupture of a uterine vein. Although uterine rupture occurs more commonly in the multiparous population, it cannot be assumed that the primigravid uterus is immune to rupture.