Obstetrics and Gynecology Service, Cruces University Hospital, Vizcaya, Spain.
Int J Gynaecol Obstet. 2011 Jan;112(1):48-51. doi: 10.1016/j.ijgo.2010.07.023. Epub 2010 Sep 25.
To determine the factors associated with the success rate of external cephalic version (ECV) for breech presentation at term.
A prospective analysis of 500 ECV maneuvers. The variables maternal age, maternal weight, body mass index, previous cesarean delivery, gestational age, parity, amount of amniotic fluid, placental location, and type of breech were studied using logistic regression analysis.
The success rate of ECV was 52.2% (n=261). The variables significantly associated with success were parity, placental location, amount of amniotic fluid, and type of breech (P<0.05). A parity of 2 had a 3.74-times higher probability of success than nulliparity (95% CI, 2.37-5.90); a posterior placenta increased the success rate by 2.85 times compared with an anterior placenta (95% CI, 1.87-4.36); and double footling breech presentation had a 2.77-times higher success rate compared with a frank breech presentation (95% CI, 1.16-6.62). The area under the ROC curve showed a predictive ability of 73.6% (95% CI, 69.2%-77.9%) for these 3 variables.
Parity, placental location, amount of amniotic fluid, and type of breech presentation were associated with the success rate of ECV.
确定与足月臀位外倒转术（ECV）成功率相关的因素。
对 500 例 ECV 操作进行前瞻性分析。使用逻辑回归分析研究了产妇年龄、体重、体重指数、既往剖宫产史、孕龄、产次、羊水数量、胎盘位置和臀位类型等变量。
ECV 的成功率为 52.2%（n=261）。与成功显著相关的变量是产次、胎盘位置、羊水数量和臀位类型（P<0.05）。产次为 2 的成功概率是初产妇的 3.74 倍（95%CI，2.37-5.90）；后位胎盘的成功率比前位胎盘高 2.85 倍（95%CI，1.87-4.36）；双足先露的成功率比单足先露高 2.77 倍（95%CI，1.16-6.62）。ROC 曲线下面积显示这 3 个变量对 ECV 成功率的预测能力为 73.6%（95%CI，69.2%-77.9%）。
产次、胎盘位置、羊水数量和臀位类型与 ECV 的成功率相关。
