Dietz H P, Lanzarone V, Simpson J M
University of Sydney, Camperdown and Penrith, Australia.
Ultrasound Obstet Gynecol. 2006 Apr;27(4):409-15. doi: 10.1002/uog.2731.
Unplanned operative delivery (vaginal or abdominal) is associated with maternal anxiety, maternal and neonatal morbidity and increased resource use. We aimed to identify potential predictors for emergency operative delivery.
This was a prospective observational study of 202 nulliparous women in a tertiary antenatal unit between 36 and 40 weeks' gestation. The assessment included an interview, a vaginal examination for Bishop score (optional), and a translabial ultrasound examination performed with the woman in a supine position and after voiding to determine cervical length, bladder position on Valsalva, and fetal head engagement. Clinical data were obtained from the institutional obstetric database and patient records.
In the late third trimester, body mass index (P = 0.016), maternal age at due date (P < 0.0001), history of Cesarean section in first-degree relatives (P = 0.009), Bishop score (P = 0.0004), cervical length (P = 0.001), bladder position on Valsalva (P = 0.003) and head engagement (P < 0.0001) were significantly associated with delivery mode. On multivariate logistic regression analysis, the best model for predicting normal vaginal delivery contained maternal age, history of Cesarean section, Bishop score and bladder position on Valsalva and had excellent ability to discriminate between normal vaginal delivery and operative delivery (c = 0.85). The model with the best ability to discriminate between vaginal delivery and Cesarean section contained the same parameters plus body mass index; this model performed even better (c = 0.87).
Identification of women at increased risk of operative delivery appears feasible. A combination of clinical and ultrasound variables yielded a model that is likely to predict delivery mode accurately in up to 87% of cases. Such a model may become useful as an entry criterion for intervention trials in women at low or very high risk of operative delivery.
非计划手术分娩（阴道分娩或剖宫产）与产妇焦虑、母婴发病率增加及资源利用增多相关。我们旨在确定急诊手术分娩的潜在预测因素。
这是一项对202名初产妇进行的前瞻性观察研究，研究对象为妊娠36至40周在三级产前病房的孕妇。评估包括访谈、用于评估Bishop评分的阴道检查（可选）以及在孕妇仰卧位且排尿后进行的经阴唇超声检查，以确定宫颈长度、瓦尔萨尔瓦动作时膀胱位置及胎头入盆情况。临床数据来自机构产科数据库和患者记录。
在妊娠晚期，体重指数（P = 0.016）、预产期时的产妇年龄（P < 0.0001）、一级亲属剖宫产史（P = 0.009）、Bishop评分（P = 0.0004）、宫颈长度（P = 0.001）、瓦尔萨尔瓦动作时膀胱位置（P = 0.003）及胎头入盆情况（P < 0.0001）与分娩方式显著相关。多因素逻辑回归分析显示，预测正常阴道分娩的最佳模型包含产妇年龄、剖宫产史、Bishop评分及瓦尔萨尔瓦动作时膀胱位置，且在区分正常阴道分娩和手术分娩方面具有出色能力（c = 0.85）。区分阴道分娩和剖宫产的最佳能力模型包含相同参数以及体重指数；该模型表现更佳（c = 0.87）。
识别手术分娩风险增加的女性似乎可行。临床和超声变量的组合产生了一个模型，该模型在高达87%的病例中可能准确预测分娩方式。这样的模型可能作为低或极高手术分娩风险女性干预试验的入选标准而发挥作用。
