Coexistence of Ovarian Endometrioma and Ovarian Pregnancy: A Case Report.

Both ovarian pregnancy and endometrioma can rupture and cause life-threatening hemoperitoneum. However, little is known about their coexistence. We report the case of a 34-year-old Japanese woman with a life-threatening hemoperitoneum in the first trimester coexisting with ovarian endometrioma and ovarian pregnancy. The patient was hospitalized in our department for acute hypogastric pain and massive hemoperitoneum during pregnancy. She had a history of miscarriage at eight weeks of gestation one year prior. Her serum beta-human chorionic gonadotropin (hCG) level was >2,000 mIU/mL. Also, a transvaginal ultrasound showed an empty uterus, an intact right ovary, an inhomogeneous left ovary, and a massive hemoperitoneum. An exploratory laparoscopy revealed a rupture of the left ovarian endometrioma, a left corpus luteal cyst, and intraperitoneal bleeding of approximately 1,200 mL. However, no ectopic lesions were observed. Microscopic examination revealed an endometriotic cyst with decidual changes in the stroma, a corpus luteal cyst, and chorionic villi with hemorrhage. Serum beta-hCG levels became negative on the 27th postoperative day. The postoperative course was uneventful. This case shows that, in addition to the differential diagnosis of ovarian pregnancy from ovarian endometrioma, clinicians should consider the coexistence of both conditions.