A diagnostically challenging case of interstitial ectopic pregnancy with multiple myomas

Abstract

  Interstitial ectopic pregnancy is rare but the frequency is increasing. It is important to diagnose and treat at an early stage to avoid massive hemorrhage due to rupture. We report a diagnostically challenging case of interstitial ectopic pregnancy associated with multiple myomas. A 34-year-old woman (gravida 0) was referred to our hospital because of possible ectopic pregnancy. She was pregnant by artificial insemination on the 36th day of her last menstrual period; however, a gestational sac (GS) was not seen in the uterine cavity and the serum human chorionic gonadotropin (hCG) level was 2,993 mIU/ml. Laparoscopic surgery was performed the same day. Intraoperative examination revealed that the uterus was enlarged by multiple myomas; the bilateral adnexa were normal in appearance. Villi were not observed intraperitoneally. Intrauterine curettage was performed, but only decidual tissue was histopathologically confirmed. Serum hCG increased to 2,555 mIU/ml 10 days after surgery, but a GS was still not observed. Enhanced computed tomography was performed because the pregnancy status was uncertain. An enhanced cystic mass was observed, suggesting a right interstitial ectopic pregnancy. Repeat laparoscopic surgery was performed. After local injection of vasopressin into the right fundus, the uterine wall was incised and villus-like tissue was confirmed in the interstitial portion of the right tube. We removed villi as much as possible and sutured the myometrium. Villi were confirmed histopathologically. Serum hCG promptly decreased and the postoperative course was uneventful.