Rizzo Giuseppe, Aiello Elisa, Bosi Costanza, D'Antonio Francesco, Arduini Domenico
Department of Obstetrics and Gynecology, University of Rome Tor Vergata, Rome, Italy.
Women's and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway.
Acta Obstet Gynecol Scand. 2017 Aug;96(8):1006-1011. doi: 10.1111/aogs.13162. Epub 2017 May 30.
The aim of this study was to ascertain whether combined ultrasound assessment of fetal head circumference (HC) and maternal subpubic angle (SPA) prior to the onset of labor may predict the likelihood of an unplanned operative delivery (UOD) in nulliparous women at term.
Prospective cohort study of singleton pregnancies in cephalic presentation. Pregnancies experiencing UOD secondary to fetal distress were excluded. HC was assessed transabdominally and SPA values were obtained from a reconstructed coronal plane on three-dimensional (3D) ultrasound performed translabially at 36-38 weeks of gestation. Maternal characteristics, HC expressed as multiple of median, and SPA were compared according to the mode of delivery. Logistic regression and receiver operating characteristics curve analyses were used to analyze the data.
597 pregnancies were included in the study. Spontaneous vaginal delivery occurred in 70.2% of the cases and UOD was required in 29.8%. There was no difference in pregnancy characteristics and birthweight between women who had a spontaneous vaginal birth compared with UOD. The HC multiple of median was larger (1.00 ± 0.02 vs. 1.03 ± 0.02, p ≤ 0.0001), whereas SPA was narrower in the UOD group (124.02 ± 13.64 vs. 102.61 ± 16.13, p ≤ 0.0001). At logistic regression, SPA (OR 0.91, 95% CI 0.89-0.93), HC multiple of median (OR 1.13, 95% CI 1.09-1.17) and maternal height (OR 0.95, 95% CI 0.92-0.99) were independently associated with UOD. When combined, the diagnostic accuracy of a predictive model integrating HC, SPA and maternal height was highly predictive of UOD with an area under the curve of 0.904 (95% CI 0.88-0.93).
Ultrasound assessment of fetal HC and maternal SPA after 36 weeks of gestation can identify a subset of women at higher risk of UOD during labor, for whom early planned delivery might be beneficial.
本研究的目的是确定在临产前联合超声评估胎儿头围（HC）和母体耻骨下角（SPA）是否可以预测足月初产妇计划外手术分娩（UOD）的可能性。
对头位单胎妊娠进行前瞻性队列研究。排除因胎儿窘迫导致UOD的妊娠。在妊娠36 - 38周时经腹评估HC，并通过经阴唇三维（3D）超声重建冠状面获得SPA值。根据分娩方式比较产妇特征、以中位数倍数表示的HC和SPA。采用逻辑回归和受试者工作特征曲线分析来分析数据。
本研究纳入597例妊娠。70.2%的病例为自然阴道分娩，29.8%需要UOD。自然阴道分娩的妇女与UOD的妇女在妊娠特征和出生体重方面没有差异。UOD组的HC中位数倍数更大（1.00±0.02对1.03±0.02，p≤0.0001），而SPA更窄（124.02±13.64对102.61±16.13，p≤0.0001）。在逻辑回归中，SPA（比值比0.91，95%可信区间0.89 - 0.93）、HC中位数倍数（比值比1.13，95%可信区间1.09 - 1.17）和产妇身高（比值比0.95，95%可信区间0.92 - 0.99）与UOD独立相关。当联合使用时，整合HC、SPA和产妇身高的预测模型的诊断准确性对UOD具有高度预测性，曲线下面积为0.904（95%可信区间0.88 - 0.93）。
妊娠36周后超声评估胎儿HC和母体SPA可以识别分娩期间UOD风险较高的一部分妇女，对她们进行早期计划分娩可能有益。
