Okafor Chigozie G, Eleje George U, Ikechebelu Joseph I, Okafor Chisolum O, Nwosu Betrand O, Okafor Chidinma C, Udigwe Gerald O, Mamah Johnbosco E, Ezema Evaristus C, Ogabido Chukwudi A, Obiagwu Hillary I, Okoro Chukwuemeka C, Njoku Tobechi K, Olisa Chinedu L, Okaforcha Emmanuel I, Okonkwo Ifeanyi O, Okafor Lazarus U, Okoye Kelechi U, Nnabuchi Obinna K, Agbanu Chiemezie M, Eke Ahizechukwu C
Department of Obstetrics and Gynaecology, Nnamdi Azikiwe University Teaching Hospital, Nnewi, Nigeria.
Department of Obstetrics and Gynaecology, Nnamdi Azikiwe University, Awka, Nigeria.
Ultrasound. 2024 Nov 7:1742271X241288156. doi: 10.1177/1742271X241288156.
The inducibility of the cervix for labour induction is usually determined by cervical status evaluation. The Bishop score is historically used to forecast the success of induction of labour, although it is subjective, and not reproducible. However, transvaginal ultrasound measurements of cervical length are rarely used for preinduction cervical assessment. The study compared cervical length measured via transvaginal ultrasound and the modified Bishop score for preinduction cervical assessment at term.
The study involved 72 pregnant, nulliparous women for induction of labour at term. They were randomised into the transvaginal ultrasound group and the modified Bishop score group. The cervix was said to be 'ripe' when the transvaginal ultrasound cervical length (CL) was < 28 mm or the modified Bishop score was ⩾ 6. The cervix was considered 'unripe' when the Bishop score was < 6 or the transvaginal ultrasound was ⩾ 28 mm. Participants with ripe cervices had induction of labour with an oxytocin infusion, while those with unripe cervices had preinduction cervical ripening with misoprostol. The primary outcome measures were the mode of delivery and the total amount of prostaglandins administered for preinduction cervical ripening.
There was no significant difference between the two groups with regard to the mode of delivery ( = 0.795), the total amount of prostaglandins administered for preinduction cervical ripening (105.0 ± 51.04 µg vs 111.90 ± 52.2 µg; = 0.0671), the proportion of women who were administered prostaglandins due to an unfavourable cervix (41.7% vs 55.6%; = 0.812), induction-to-the-active phase of the labour interval (11.00 ± 4.2 hours vs 11.82 ± 4.12 hours; = 0.407) or the induction-delivery interval (20.15 ± 5.7 hours vs 22.66 ± 4.33 hours; = 0.06) in both groups, respectively. Compared with those in the Bishop score group (Bishop score ⩾ 6), the induction-to-active phase of labour intervals (6.47 ± 0.77 hours vs 7.33 ± 1.21 hours, = 0.024) and the induction-to-delivery intervals (14.97 ± 1.0 hours vs 18.39 ± 0.85 hours; = 0.0001) in the transvaginal ultrasound group (cervical length < 28 mm) were significantly shorter, respectively.
Preinduction cervical assessment using transvaginal ultrasound (cervical length < 28 mm) or the modified Bishop score is a successful predictor of the outcome of labour induction A larger multicentre studies are needed to identify optimal cervical length cutoffs and to determine if this could decrease unnecessary prostaglandin use or decrease caesarean section rate.
引产时宫颈的可诱导性通常通过宫颈状况评估来确定。尽管Bishop评分具有主观性且不可重复，但一直以来都被用于预测引产的成功率。然而，经阴道超声测量宫颈长度很少用于引产术前的宫颈评估。本研究比较了经阴道超声测量的宫颈长度和改良Bishop评分在足月引产术前宫颈评估中的应用。
本研究纳入了72例足月妊娠、初产妇且计划引产的女性。她们被随机分为经阴道超声组和改良Bishop评分组。当经阴道超声测量的宫颈长度（CL）<28mm或改良Bishop评分≥6时，宫颈被认为是“成熟的”。当Bishop评分<6或经阴道超声测量≥28mm时，宫颈被认为是“不成熟的”。宫颈成熟的参与者采用缩宫素静脉滴注引产，而宫颈不成熟的参与者则采用米索前列醇进行引产术前的宫颈成熟。主要观察指标为分娩方式和引产术前宫颈成熟所用前列腺素的总量。
两组在分娩方式（P=0.795）、引产术前宫颈成熟所用前列腺素的总量（105.0±51.04μg vs 111.90±52.2μg；P=0.0671）、因宫颈条件不佳而使用前列腺素的女性比例（41.7% vs 55.6%；P=0.812）、引产至活跃期的时间间隔（11.00±4.2小时 vs 11.82±4.12小时；P=0.407）或引产至分娩的时间间隔（20.15±5.7小时 vs 22.66±4.33小时；P=0.06）方面均无显著差异。与Bishop评分组（Bishop评分≥6）相比，经阴道超声组（宫颈长度<28mm）的引产至活跃期的时间间隔（6.47±0.77小时 vs 7.33±1.21小时，P=0.024）和引产至分娩的时间间隔（14.97±1.0小时 vs 18.39±0.85小时；P=0.0001）明显更短。
使用经阴道超声（宫颈长度<28mm）或改良Bishop评分进行引产术前的宫颈评估是引产结局的成功预测指标。需要开展更大规模的多中心研究来确定最佳的宫颈长度临界值，并确定这是否可以减少不必要的前列腺素使用或降低剖宫产率。
