Department of Midwifery, King's College London, London, UK.
Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust, London, UK.
Health Technol Assess. 2017 Nov;21(65):1-176. doi: 10.3310/hta21650.
Epidural analgesia leads to increased risk of instrumental vaginal delivery (IVD). There is debate about whether or not posture in second-stage labour influences the incidence of spontaneous vaginal birth (SVB).
In nulliparous women with epidural analgesia, does a policy of adopting an 'upright position' throughout second-stage labour increase the incidence of SVB compared with a policy of adopting a 'lying-down' position?
Two-arm randomised controlled trial.
Maternity units in England and Wales.
Nulliparous women aged ≥ 16 years, at ≥ 37 weeks' gestation with singleton cephalic presentation and intended SVB, in second-stage labour with an epidural providing effective pain relief.
(1) Upright position to maintain the pelvis in as vertical a plane as possible; and (2) lying-down position to maintain the pelvis in as horizontal a plane as possible.
The primary outcome measure was incidence of SVB. Secondary outcomes included augmentation, interventions to maintain blood pressure, duration of labour, episiotomy, genital tract trauma, post-partum haemorrhage, maternal satisfaction, neonatal metabolic acidosis, 5-minute Apgar score of < 4, resuscitation at birth and admission to neonatal unit. At 1 year for (1) women: urinary or faecal incontinence, dyspareunia and health-related quality of life; (2) for infants: major morbidity. A cost-consequences analysis with a time horizon of 1 year after the birth from a NHS perspective.
Between October 2010 and January 2014, 3236 women were randomised from 41 centres in England and Wales. There was a statistically significant difference in the incidence of SVB between groups, with 35.2% of women achieving a SVB in the upright group, compared with 41.1% in the lying-down group (adjusted risk ratio 0.86, 95% confidence interval 0.78 to 0.94). There was no evidence of differences in most of the secondary maternal or neonatal outcomes, or in long-term outcomes at the 12-month follow-up. No significant overall cost differences were observed between upright and lying-down positions for mothers or their babies.
Measurement of adherence was challenging in this unmasked trial, and adherence could be influenced by midwives' beliefs about the allocated positions. If adherence was poor, this would have diluted the difference between the two groups.
There is clear evidence of the benefit of adopting a lying-down position in second-stage labour in nulliparous women with epidural analgesia, with no apparent disadvantages in either short- or long-term outcomes for mother or baby, and this is cost neutral for the NHS.
Questions remain about whether or not other positions could increase the incidence of SVB further in this group of women. The results also raise questions about the role of maternal position in second-stage labour in women without an epidural.
Current Controlled Trials ISRCTN35706297.
This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in , Vol 21, No. 65. See the NIHR Journals Library website for further project information.
硬膜外镇痛会增加器械性阴道分娩(IVD)的风险。关于第二产程中的体位是否会影响自然阴道分娩(SVB)的发生率存在争议。
在接受硬膜外镇痛的初产妇中,与采用“卧位”相比,采用“直立位”的政策是否会增加 SVB 的发生率?
双臂随机对照试验。
英格兰和威尔士的产科病房。
年龄≥ 16 岁、≥ 37 周妊娠、单胎头位、计划行 SVB、第二产程有硬膜外镇痛且疼痛缓解有效的初产妇。
(1)直立位,使骨盆尽可能保持垂直;(2)卧位,使骨盆尽可能保持水平。
主要结局指标为 SVB 的发生率。次要结局指标包括催产、维持血压的干预措施、产程持续时间、会阴切开术、生殖道创伤、产后出血、产妇满意度、新生儿代谢性酸中毒、5 分钟 Apgar 评分<4、出生时复苏和新生儿病房入院。在 1 年时,(1)女性:尿失禁或粪失禁、性交困难和健康相关生活质量;(2)婴儿:主要发病率。从 NHS 角度进行了具有 1 年时间范围的成本-后果分析。
2010 年 10 月至 2014 年 1 月,英格兰和威尔士的 41 个中心随机抽取了 3236 名女性。两组间 SVB 的发生率存在统计学显著差异,直立组有 35.2%的女性实现了 SVB,卧位组为 41.1%(调整后的风险比 0.86,95%置信区间 0.78 至 0.94)。在大多数次要的产妇或新生儿结局,或在 12 个月随访时的长期结局方面,没有证据表明存在差异。对于母亲或婴儿,直立位和卧位之间没有观察到明显的总体成本差异。
在这项非盲试验中,对依从性的测量具有挑战性,并且助产士对分配体位的信念可能会影响依从性。如果依从性差,这将削弱两组之间的差异。
在接受硬膜外镇痛的初产妇中,第二产程采用卧位有明确的获益,母婴短期和长期结局均无明显不利影响,对 NHS 而言也无成本增加。
关于在这群女性中,其他体位是否可以进一步提高 SVB 的发生率,仍存在疑问。该结果还提出了关于在没有硬膜外镇痛的女性中第二产程中产妇体位作用的问题。
当前对照试验 ISRCTN35706297。
本项目由英国国家卫生研究院卫生技术评估计划资助,将发表在《英国医学杂志》第 21 卷第 65 期。有关该项目的更多信息,请访问英国国家卫生研究院期刊图书馆网站。