Uterine Rupture and Subsequent Uterine Artery Pseudoaneurysm Following Second‐Trimester Medical Abortion With Vaginal Gemeprost in an Unscarred Uterus: A Case Report

A 44‐year‐old Japanese woman with no history of uterine surgery or trauma was admitted for pregnancy termination at 20 weeks due to a fetal abnormality. A vaginal gemeprost pessary was administered into the posterior fornix under prescribed doses. During the second day of treatment, she developed hemorrhagic shock from a uterine rupture (UR) in the lower myometrial segment, with the uterovesical serosa remaining intact. She required massive transfusion therapy and a hysterectomy and was initially recovering. However, 3 days postoperation, she exhibited significant abdominal bleeding due to rupture of a uterine artery pseudoaneurysm (UAP), which required hemostatic surgery. This novel case highlights the risk of UR during second‐trimester medical abortion (STMA) with gemeprost, even in unscarred uteri. Detection of cervical displacement via vaginal examination may lead to the diagnosis of UR. Laparotomy should be performed following cardiovascular collapse, even if an ultrasonography could not reveal intraperitoneal bleeding. Additionally, the varied anatomical damage to the uterus can result in complicating the conventional surgical approach and contributing to the formation of a pseudoaneurysm. Such extraordinary cases are best managed by experienced clinicians and skilled surgical teams.