Objective

This study aimed to assess the efficacy of sonographic assessment of fetal occiput position before operative vaginal delivery to decrease the number of failed operative vaginal deliveries.

Data Sources

The search was conducted in MEDLINE, Embase, Web of Science, Scopus, ClinicalTrial.gov, Ovid, and Cochrane Library as electronic databases from the inception of each database to April 2021. No restrictions for language or geographic location were applied.

Study Eligibility Criteria

Selection criteria included randomized controlled trails of pregnant women randomized to either sonographic or clinical digital diagnosis of fetal occiput position during the second stage of labor before operative vaginal delivery.

Methods

The primary outcome was failed operative vaginal delivery, defined as a failed fetal operative vaginal delivery (vacuum or forceps) extraction requiring a cesarean delivery or forceps after failed vacuum. The summary measures were reported as relative risks or as mean differences with 95% confidence intervals using the random effects model of DerSimonian and Laird. An I² (Higgins I²) >0% was used to identify heterogeneity.

Results

A total of 4 randomized controlled trials including 1007 women with singleton, term, cephalic fetuses randomized to either the sonographic (n=484) or clinical digital (n=523) diagnosis of occiput position during the second stage of labor before operative vaginal delivery were included. Before operative vaginal delivery, fetal occiput position was diagnosed as anterior in 63.5% of the sonographic diagnosis group vs 69.5% in the clinical digital diagnosis group (P=.04). There was no significant difference in the rate of failed operative vaginal deliveries between the sonographic and clinical diagnosis of occiput position groups (9.9% vs 8.2%; relative risk, 1.14; 95% confidence interval, 0.77–1.68). Women randomized to sonographic diagnosis of occiput position had a significantly lower rate of occiput position discordance between the evaluation before operative vaginal delivery and the at birth evaluation when compared with those randomized to the clinical diagnosis group (2.3% vs 17.7%; relative risk, 0.16; 95% confidence interval, 0.04–0.74; P=.02). There were no significant differences in any of the other secondary obstetrical and perinatal outcomes assessed.

Conclusion

Sonographic knowledge of occiput position before operative vaginal delivery does not seem to have an effect on the incidence of failed operative vaginal deliveries despite better sonographic accuracy in the occiput position diagnosis when compared with clinical assessment. Future studies should evaluate how a more accurate sonographic diagnosis of occiput position or other parameters can lead to a safer and more effective operative vaginal delivery technique.

中文翻译：

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枕骨位置的超声知识以减少阴道手术失败：随机对照试验的系统评价和荟萃分析

客观的

本研究旨在评估在阴道手术分娩前对胎儿枕骨位置进行超声评估以减少阴道手术分娩失败次数的效果。

数据源

从每个数据库开始到 2021 年 4 月，搜索是在 MEDLINE、Embase、Web of Science、Scopus、ClinicalTrial.gov、Ovid 和 Cochrane 图书馆作为电子数据库进行的。没有应用语言或地理位置的限制。

学习资格标准

选择标准包括在手术阴道分娩前的第二产程期间随机分配到胎儿枕骨位置的超声或临床数字诊断的孕妇的随机对照试验。

方法

主要结局是阴道手术分娩失败，定义为胎儿阴道分娩（真空或产钳）失败，在真空失败后需要剖宫产或产钳。使用 DerSimonian 和 Laird 的随机效应模型将汇总测量报告为相对风险或具有 95% 置信区间的平均差异。I ² (Higgins I ² ) >0% 用于识别异质性。

结果

共有 4 项随机对照试验，包括 1007 名单胎、足月、头胎的女性，在阴道分娩前第二产程期间随机接受超声（n = 484）或临床数字（n = 523）枕位诊断。包括。手术阴道分娩前，超声诊断组63.5%的胎儿枕位被诊断为前位，临床数字诊断组为69.5%（P=.04)。枕位组的超声诊断和临床诊断的阴道分娩失败率没有显着差异（9.9% vs 8.2%；相对风险，1.14；95% 置信区间，0.77-1.68）。与随机分配到临床诊断组的女性相比，随机接受枕位超声诊断的女性在阴道分娩前评估和出生时评估之间的枕位不一致率显着降低（2.3% vs 17.7%；相对风险，0.16 ; 95% 置信区间, 0.04–0.74; P =.02)。评估的任何其他次要产科和围产期结局均无显着差异。

结论

尽管与临床评估相比，枕位诊断的超声准确性更高，但阴道分娩前枕位的超声知识似乎对阴道分娩失败的发生率没有影响。未来的研究应该评估更准确的枕骨位置或其他参数的超声诊断如何导致更安全和更有效的阴道分娩技术。