Ruptured Hemorrhagic Corpus Luteum Cyst in an Undescended Ovary: A Rare Cause of Acute Abdomen

Abstract Background Undescended ovaries are typically detected during infertility evaluations and are frequently associated with uterine malformations. Ruptured hemorrhagic corpus luteum cyst of an undescended ovary is an unusual cause of acute abdomen in an adolescent. Case A 15-year-old girl presented with right lower quadrant pain, nausea, and vomiting, and transabdominal sonography and magnetic resonance imaging of the pelvis showed a 10 cm × 5 cm sized cystic mass at the level of the pelvic brim, anterior to the psoas muscle suggestive of a retroperitoneal hemorrhagic cyst. At surgery, the uterus and left adnexa appeared normal, but the right ovary was not visible within the pelvic cavity, and the right pelvic retroperitoneum was distended. After opening the retroperitoneum and aspirating blood clots, the undescended ovary with a ruptured cyst was visualized within the retroperitoneum. Right ovarian wedge resection was performed and the right ovary was repositioned in the pelvic cavity. Summary and Conclusion Rupture of a corpus luteum cyst in an undescended ovary should be included in the differential diagnosis of acute abdomen in adolescents.