Shakya S, Shrestha A
Department of Obstetrics and Gynecology, Dhulikhel Hospital, Kathmandu University Hospital, Kathmandu University School of Medical Sciences, Dhulikhel, Kavre, Nepal.
Kathmandu Univ Med J (KUMJ). 2024 Apr-Jun;22(86):202-209.
Background Induction is one of the most common interventions in obstetrics practice, accounting for 1.4-35%. Cervical favorability is crucial for successful induction. The Bishop score is simple and assesses preinduction cervical favorability based on five components. However, it has high inter- and intra-observer variability. Alternative objective methods are transvaginal ultrasound parameters (e.g., cervical length, width, and funneling). Objective To assess and compare the predictive value of transvaginal ultrasound and bishop score for vaginal delivery. In addition, the time interval from induction to delivery in women undergoing induction of labor. Method This prospective cross-sectional study included 342 pregnant women, in whom induction of labor was performed at 38-42 weeks of gestation. Cervical length, funneling, and width from transvaginal sonography and bishop scores by digital examination are assessed prior to induction in high-risk cases according to standard protocol. Result In our study, both transvaginal cervical length and bishop score showed similar predictors of successful labor induction, i.e., vaginal delivery. The ROC curve for cervical length showed an optimal cut-off value of ≤ 32 mm, corresponding to a sensitivity of 64.2% and a specificity of 60.0%, whereas the optimal cut-off value for Bishop score was ≥ 5, with a sensitivity of 65.1% and a specificity of 62.0%. However, cervical width and the presence of cervical funneling did not correlate. Both cervical length and Bishop score had a significant correlation as predictors of successful induction, with an OR of 0.93 (95% CI 0.91-0.96), an AOR of 0.96 (955 CI 0.9-0.99), and an OR of 1.41 (95% CI 1.2-1.6) and an AOR 1.2 (95% CI 1.1-1.5), respectively. Conclusion Cervical length and bishop score are both good and equally predict of successful induction of labor.
引产是产科实践中最常见的干预措施之一，占比1.4%-35%。宫颈成熟度对引产成功至关重要。 Bishop评分简单，基于五个组成部分评估引产前置宫颈成熟度。然而，其观察者间和观察者内的变异性较高。替代的客观方法是经阴道超声参数（如宫颈长度、宽度和漏斗形成）。目的：评估并比较经阴道超声和Bishop评分对阴道分娩的预测价值。此外，还要研究引产妇女从引产到分娩的时间间隔。方法：这项前瞻性横断面研究纳入了342名孕妇，她们在妊娠38-42周时进行引产。根据标准方案，在高危病例引产之前，通过经阴道超声检查评估宫颈长度、漏斗形成和宽度，并通过指诊评估Bishop评分。结果：在我们的研究中，经阴道宫颈长度和Bishop评分均显示出相似的引产成功预测指标，即阴道分娩。宫颈长度的ROC曲线显示最佳截断值≤32mm，对应灵敏度为64.2%，特异度为60.0%，而Bishop评分的最佳截断值≥5，灵敏度为65.1%，特异度为62.0%。然而，宫颈宽度与宫颈漏斗形成并无关联。宫颈长度和Bishop评分作为引产成功的预测指标均具有显著相关性，其比值比分别为0.93（95%可信区间0.91-0.96）、校正比值比为0.96（95%可信区间0.9-0.99），以及比值比为1.41（95%可信区间1.2-1.6）和校正比值比为1.2（95%可信区间1.1-1.5）。结论：宫颈长度和Bishop评分都是引产成功的良好且同等的预测指标。
