应用经会阴超声测量子宫宫颈前角（ACA）及宫颈长度（CL），研究ACA、CL在预测早产中的应用价值。

选取2018年5月至2019年5月于南京医科大学附属苏州医院产检、孕龄>28周、诊断为先兆早产或存在早产高危因素的孕妇253例。依据妊娠结局，将253例孕妇分为早产组54例，足月产组199例。所有孕妇均行经会阴超声检查，测量ACA与CL，分析早产组与足月产组ACA与CL的差异以及ACA和CL预测早产的效能。

本研究早产组CL平均值为（26.18±4.33）mm，小于足月产组的（31.36±3.33）mm，差异有统计学意义（t=8.63，P<0.05）；早产组的ACA平均值大于足月产组［（117.50±9.61）° vs（102.35±7.59）°］，差异有统计学意义（t=-13.428，P<0.05）。本研究253例孕妇，CL预测早产的ROC曲线下面积为0.811（P<0.05）；最佳界值为25.5 mm；其预测早产的敏感度、特异度、阳性预测值、阴性预测值及准确性分别为97.0%、51.9%、82.3%、88.1%、72.4%。ACA预测早产的ROC曲线下面积为0.921（P<0.05），最佳界值为115.5°，其预测早产的敏感度、特异度、阳性预测值、阴性预测值及准确性分别为83.3%、95.5%、83.3%、95.4%、92.7%。

经会阴超声检查测量ACA及CL在预测早产发生中具有一定的临床应用价值，ACA的预测效能略高于CL。经会阴超声操作简便易行、可重复性高，值得临床推广应用。

To assess the value of the anterior uterocervical angle (ACA) and cervical length (CL) measured by trans-perineum ultrasound in the prediction of premature delivery.

From May 2018 to May 2019, a total of 253 pregnant women at a gestational age of more than 28 weeks who were diagnosed as threatened preterm labor or had high risk factors of preterm labor were selected. According to the pregnancy outcome, the 253 pregnant women were divided into a preterm labor group (54 cases) and a term labor group (199 cases). All pregnant women were examined by trans-perineum ultrasound, and the ACA and CL were measured. The difference in the ACA and CL between the preterm labor group and term labor group was analyzed.

The average value of the CL in the preterm labor group was (26.18±4.33) mm, which was significantly smaller than that in the term labor group (31.36±3.33) mm (t=8.63, P<0.05). The mean value of the ACA in preterm labor group was significantly higher than that in the term labor group [(117.50±9.61)° vs (102.35±7.59)°, t=-13.428, P<0.05]. In the 253 pregnant women, the area under the receiver operating characteristic (ROC) curve of the CL for predicting preterm delivery was 0.811, and the optimal diagnostic threshold was 25.5 mm; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 97.0%, 51.9%, 82.3%, 88.1%, and 72.4%, respectively. The area under the ROC curve of the ACA for predicting preterm delivery was 0.921, and the optimal diagnostic threshold was 115.5°; the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 83.3%, 95.5% , 83.3% , 95.4%, and 92.7%, respectively.

Measuring the ACA and CL by trans-perineum ultrasound has appreciated clinical value in predicting preterm birth, and the ACA is slightly superior to the CL. Since tran-perineum ultrasound is easy to operate and highly repeatable, it is worthy of clinical application.