Department of Obstetrics and Gynecology, Kaplan Medical Center, Rehovot, Israel, affiliated to the Hebrew University and Hadassah Faculty of Medicine, Jerusalem, Israel.
Department of Obstetrics and Gynecology, Kaplan Medical Center, Rehovot, Israel, affiliated to the Hebrew University and Hadassah Faculty of Medicine, Jerusalem, Israel.
Am J Obstet Gynecol MFM. 2021 Jan;3(1):100249. doi: 10.1016/j.ajogmf.2020.100249. Epub 2020 Oct 19.
Longer duration of active pushing during labor is associated with a higher rate of operative delivery and an increased risk of maternal and neonatal complications. Although immediate pushing at complete dilatation is associated with lower rates of chorioamnionitis and postpartum hemorrhage, it is also associated with a longer duration of pushing.
This study aimed to evaluate whether fetal head station and position, as assessed by ultrasound at the beginning of the pushing process, can predict the mode of delivery and duration of pushing in nulliparous women.
This prospective observational study included nulliparous women with neuraxial analgesia and complete cervical dilatation. The following sonographic parameters were assessed just before the beginning of the pushing process, at rest, and while pushing during contraction: head position, angle of progression, head-perineum distance, and head-symphysis distance. The change between rest and pushing was designated as delta angle of progression, delta head-perineum distance, and delta head-symphysis distance. The sonographic measurements and fetal head station assessed by vaginal examination were compared between women who had a spontaneous vaginal delivery to those who underwent an operative delivery, and between those who pushed for more or less than 1 hour.
Of the 197 women included in this study, 166 (84.3%) had a spontaneous vaginal delivery, 31 (15.7%) had an operative delivery, 23 (11.6%) had a vacuum delivery, and 8 (4.0%) had a cesarean delivery. Spontaneous vaginal delivery and shorter duration of pushing (less than an hour) were significantly more common with a nonocciput posterior position (10.6% vs 47.3%; P<.005), a wider angle of progression, a shorter head-perineum distance and head-symphysis distance (both during rest and while pushing), and a lower fetal head station as assessed by digital vaginal examination. However, a logistic regression model revealed that only the angle of progression at rest and the delta angle of progression were independently associated with a spontaneous vaginal delivery with an area under the curve of 0.82 (95% confidence interval, 0.76-0.87; P<.0001) and 0.75 (95% confidence interval, 0.67-0.79; P<.0001), respectively.
Ultrasound performed at the beginning of the active second stage of labor can assist in predicting the mode of delivery and duration of pushing and perform better than the traditional digital examination, with the angle of progression at rest and delta angle of progression being the best predictors.
分娩过程中主动用力时间延长与剖宫产率升高及母婴并发症风险增加有关。虽然宫口开全后即刻用力与较低的绒毛膜羊膜炎和产后出血发生率相关，但也与用力时间延长有关。
本研究旨在评估初产妇产程中超声评估的胎头位置和胎位能否预测分娩方式和产程中用力时间。
本前瞻性观察性研究纳入了接受椎管内麻醉且宫口完全扩张的初产妇。在开始用力前、休息时和宫缩时用力时，通过超声评估胎头位置、进展角度、胎头会阴距离和胎头耻骨联合距离。休息时和用力时之间的差值分别定义为进展角度差值、胎头会阴距离差值和胎头耻骨联合距离差值。比较阴道检查评估的胎先露位置和超声测量值与自然分娩产妇和需行剖宫产产妇之间的差异，比较产程中用力时间大于 1 小时和小于 1 小时的产妇之间的差异。
本研究共纳入 197 例产妇，其中 166 例（84.3%）经阴道自然分娩，31 例（15.7%）行剖宫产，23 例（11.6%）行真空吸引分娩，8 例（4.0%）行剖宫产。非枕后位（10.6% vs. 47.3%；P<.005）、进展角度更宽、胎头会阴距离和胎头耻骨联合距离在休息时和用力时更短、经阴道检查时胎先露位置更低与自然分娩和产程中用力时间更短显著相关。然而，逻辑回归模型显示，仅休息时的进展角度和进展角度差值与自然分娩独立相关，曲线下面积分别为 0.82（95%置信区间，0.76-0.87；P<.0001）和 0.75（95%置信区间，0.67-0.79；P<.0001）。
分娩活跃期早期行超声检查可辅助预测分娩方式和产程中用力时间，且优于传统的经阴道检查，其中休息时的进展角度和进展角度差值是最佳预测指标。
