Yukari Nagao,1,2 Kazuhiro Osato,2,3 Michiko Kubo,2 Takuya Kawamura,2 Tomoaki Ikeda,3 Takaharu Yamawaki2 1Department of Obstetrics and Gynecology, Japanese Red Cross Nagoya Daiichi Hospital, Aichi, 2Department of Obstetrics and Gynecology, Japanese Red Cross Ise Hospital, Mie, 3Department of Obstetrics and Gynecology, School of Medicine, Mie University, Mie, Japan Abstract: Uterine rupture rarely occurs during pregnancy, but it is a critical situation if so. It is already known that a history of uterine surgeries, such as cesarean section or myomectomy, is a risk factor for uterine rupture. Currently, the laparoscopic adenomyomectomy is a widely performed procedure, but associated risks have not been defined. We observed a case of spontaneous uterine rupture in a patient during the 35th week of gestation, after a laparoscopic adenomyomectomy. A 42-year-old, gravida 2, para 0 woman became pregnant after a laparoscopic adenomyomectomy and her pregnancy was conventional. At a scheduled date in the 35th week of gestation, after combined spinal epidural anesthesia and frequent uterine contractions, a weak pain suddenly ensued. After 13 minutes of uterine contractions, vaginal bleeding was evident. A cesarean section was performed, and the uterine rupture was found in the scar. After a laparoscopic adenomyomectomy, a pregnant uterus can easily rupture by rather weak and short uterine contractions, and is characterized by vaginal bleeding. When uterine bleeding is observed in pregnant women that have a history of adenomyomectomy, one should consider uterine rupture. Keywords: uterine rupture, pregnancy, laparoscopic adenomyomectomy, uterine contraction, vaginal bleeding