BACKGROUND: Spontaneous rupture of uterine surface varicose veins is rare but may become a serious complication of pregnancy. CASE: A 40-year-old woman, gravida 2, para 0-0-1-0, presented with worsening generalized abdominal pain after occasional nausea, vomiting and diarrhea over the previous 2 days. After a 4-hour observation period, sudden onset of severe, prolonged fetal heart rate decelerations was recognized along with frequent uterine contractions. Emergency cesarean section was performed under a tentative diagnosis of placental abruption. A live, female infant weighing 1,730 g was delivered and had Apgar scores of 5 and 9 at 1 and 5 minutes, respectively. Intraoperatively, approximately 500 mL of hemoperitoneum was present, and multiple bleeding sites from varicose veins on the posterior uterine surface were detected. Because the maternal vital signs became unstable and hemostasis was difficult, hysterectomy was performed and blood transfusion administered. CONCLUSION: Although very rare, hemoperitoneum should be included in the differential diagnosis when a pregnant woman experiences acute-onset, severe abdominal pain, even without an episode of abdominal trauma.