Mimura Takashi, Hasegawa Junichi, Nakamura Masamitsu, Matsuoka Ryu, Ichizuka Kiyotake, Sekizawa Akihiko, Okai Takashi
Department of Obstetrics and Gynecology, Showa University School of Medicine, Tokyo, Japan.
J Obstet Gynaecol Res. 2011 Jul;37(7):830-5. doi: 10.1111/j.1447-0756.2010.01446.x. Epub 2011 Mar 31.
To investigate the association between the amount of bleeding during a cesarean section and the effacement of the uterine cervix in patients with placenta previa.
This study reviewed 115 singleton pregnancies with placenta previa. In cases of placenta previa, the thickness of the uterine muscle and cervical length were retrospectively measured and compared with the amount of bleeding during the cesarean section.
No correlation was found between the amount of bleeding during the cesarean operation and the thickness of the uterine isthmus. There was a significantly negative correlation between the amount of bleeding and cervical length (r = -0.344, P < 0.001). The threshold cervical length associated with massive bleeding (>2500 mL) was 25 mm, based on an ROC curve. The relative risk for massive bleeding in cases with a short cervical length (<25 mm) was 7.2 (95% CI, 2.3-22.3) in comparison to cases with a long cervical length.
This study demonstrated that a short cervical length in cases with placenta previa was associated with massive bleeding during the operation. Short cervical length seems to be one of the warning signs for massive bleeding during the operation for placenta previa.
探讨前置胎盘患者剖宫产术中出血量与宫颈消退之间的关联。
本研究回顾了115例单胎前置胎盘妊娠病例。对于前置胎盘病例，回顾性测量子宫肌层厚度和宫颈长度，并与剖宫产术中出血量进行比较。
剖宫产术中出血量与子宫峡部厚度之间未发现相关性。出血量与宫颈长度之间存在显著负相关（r = -0.344，P < 0.001）。根据ROC曲线，与大量出血（>2500 mL）相关的宫颈长度阈值为25 mm。宫颈长度短（<25 mm）的病例发生大量出血的相对风险是宫颈长度长的病例的7.2倍（95%可信区间，2.3 - 22.3）。
本研究表明，前置胎盘病例中宫颈长度短与术中大量出血有关。宫颈长度短似乎是前置胎盘手术中大量出血的警示信号之一。
