Endometriosis-related spontaneous hemoperitoneum in the early second trimester: A case report

Objective: To present a rare case of endometriosis-related spontaneous hemoperitoneum in pregnancy (SHiP) with atypical subacute symptoms, which is likely to be mistaken as an infectious disease initially. Case report: A 35-year-old primigravid woman presented with diffuse lower abdominal pain and signs of peritoneal irritation for five days at 18 weeks’ gestation, and the initial diagnosis was acute peritonitis. An abrupt deterioration with maternal shock and stillbirth of fetus was found in spite of close observation in emergent department. Emergent laparotomy was performed for delay-appeared hemoperitoneum. Bleeding from decidualized endometriotic tissue over posterior uterine surface was found, and hemostasis was achieved with uterine preservation. The patient recovered smoothly. Conclusion: SHiP is a serious obstetric complication of endometriosis with diagnostic difficulty. Its initial presentation may mimic infectious disease, so close monitoring for possible abrupt deterioration is crucial. Early detection and timely management are the key to avoid adverse pregnancy outcomes.