大場 智洋, 長谷川 潤一, 新垣 達也, 仲村 将光, 松岡 隆, 市塚 清健, 関沢 明彦

Tomohiro OBA, Junichi HASEGAWA, Tatsuya ARAKAKI, Masamitsu NAKAMURA, Ryu MATSUOKA, Kiyotake ICHIDUKA, Akihiko SEKIZAWA

昭和大学産婦人科学講座

Department of Obstetrics and Gynecology, Showa University School of Medicine

キーワード : corneal position of uterus, placental abruption, uterine contraction

妊娠28週に卵管角部の子宮破裂を生じた1例を報告する．30歳，0回経妊，子宮手術の既往はない．妊娠26週2日，頻回な子宮収縮と性器出血を認め当科紹介になった．左側腹部に軟な腫瘤を触知した．経腹超音波検査で，腫瘤は，子宮卵管角から突出しており，中には胎盤が折りたたまれたように存在した．胎盤と子宮筋層にecho free spaceはなかった．左卵管角部の切迫子宮破裂を疑った．妊娠27週3日，超音波検査で胎盤辺縁に39×24 mm大，網状のlow echo areaを認め，胎盤辺縁血腫と診断した．妊娠28週1日，子宮収縮が頻回となり，腫瘤に圧痛を認め，超音波検査では胎盤辺縁のlow echo areaは2ヵ所あり68×19 mmと93×36 mm大と拡大していた．胎児心拍数陣痛図では，prolonged decelerationを認めた．子宮破裂，胎盤早期剥離を疑い，緊急帝王切開術を施行した．術中出血量1,065 g，出生児体重1,173 g，Apgar score（1/5分値）8/9点，臍帯動脈血pH 7.231であった．子宮左卵管角は6×7 cmに膨隆しており，子宮筋層は菲薄，断裂していた．卵管角の胎盤付着による子宮破裂と診断した．卵管角部を楔状に切除し，子宮筋層を3層縫合した．既往歴や妊娠の経過から子宮破裂の危険性が低い症例であっても，胎盤位置の異常によっては，子宮破裂に至ることもあり，その危険性を念頭に置くことが重要である．

We herein report a case with uterine corneal rupture that occurred at 28 weeks of gestation. The patient was a 30-year-old primigravida without any history of uterine surgery. She had undergone regular pregnancy check-ups from the first trimester, and a normally located gestational sac had been confirmed by ultrasound at 8 weeks of gestation. She was admitted to our hospital for uterine contractions and genital bleeding at 26 weeks of gestation. On admission, a soft mass was felt by palpation at the left lateral region of the abdomen. An ultrasound examination revealed that the mass protruded from the uterine corneal position and had folded placenta in the mass. Threatened uterine rupture was suspected. At 27 weeks’ gestation, a reticular low echo area (39×24 mm) at the margin of the placenta was visualized. Along with frequent uterine contractions and tenderness of the mass at 28 weeks’ gestation, the low echo area increased at the margin of the placenta. Prolonged deceleration was also observed. A diagnosis of uterine rupture and placental abruption was made, and an emergency cesarean section was performed. The blood loss during the operation was 1065 g. A 1173 g healthy neonate was born with an Apgar score (1/5 min) of 8/9. The bulging lesion at the left corneal position was observed, and the myometrium was noted to be thin and ruptured. Similar to the antenatal diagnosis, a uterine rupture from the corneal position of the placenta was diagnosed. Wedge resection of the ruptured uterus at the corneal position was performed using three-layered sutures. Uterine rupture may occur when the placenta is located abnormally, even in cases at low risk for uterine rupture without a past history or perinatal characteristics.