NHS Lothian Department of Obstetrics and Gynaecology, Simpson's Centre for Reproductive Health, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom.
Tommy's Centre for Maternal and Fetal Health, MRC Centre for Reproductive Health, University of Edinburgh Queen's Medical Research Institute, Edinburgh, United Kingdom.
PLoS Med. 2018 Jan 23;15(1):e1002494. doi: 10.1371/journal.pmed.1002494. eCollection 2018 Jan.
Cesarean birth rates continue to rise worldwide with recent (2016) reported rates of 24.5% in Western Europe, 32% in North America, and 41% in South America. The objective of this systematic review is to describe the long-term risks and benefits of cesarean delivery for mother, baby, and subsequent pregnancies. The primary maternal outcome was pelvic floor dysfunction, the primary baby outcome was asthma, and the primary subsequent pregnancy outcome was perinatal death.
Medline, Embase, Cochrane, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases were systematically searched for published studies in human subjects (last search 25 May 2017), supplemented by manual searches. Included studies were randomized controlled trials (RCTs) and large (more than 1,000 participants) prospective cohort studies with greater than or equal to one-year follow-up comparing outcomes of women delivering by cesarean delivery and by vaginal delivery. Two assessors screened 30,327 abstracts. Studies were graded for risk of bias by two assessors using the Scottish Intercollegiate Guideline Network (SIGN) Methodology Checklist and the Risk of Bias Assessment tool for Non-Randomized Studies. Results were pooled in fixed effects meta-analyses or in random effects models when significant heterogeneity was present (I2 ≥ 40%). One RCT and 79 cohort studies (all from high income countries) were included, involving 29,928,274 participants. Compared to vaginal delivery, cesarean delivery was associated with decreased risk of urinary incontinence, odds ratio (OR) 0.56 (95% CI 0.47 to 0.66; n = 58,900; 8 studies) and pelvic organ prolapse (OR 0.29, 0.17 to 0.51; n = 39,208; 2 studies). Children delivered by cesarean delivery had increased risk of asthma up to the age of 12 years (OR 1.21, 1.11 to 1.32; n = 887,960; 13 studies) and obesity up to the age of 5 years (OR 1.59, 1.33 to 1.90; n = 64,113; 6 studies). Pregnancy after cesarean delivery was associated with increased risk of miscarriage (OR 1.17, 1.03 to 1.32; n = 151,412; 4 studies) and stillbirth (OR 1.27, 1.15 to 1.40; n = 703,562; 8 studies), but not perinatal mortality (OR 1.11, 0.89 to 1.39; n = 91,429; 2 studies). Pregnancy following cesarean delivery was associated with increased risk of placenta previa (OR 1.74, 1.62 to 1.87; n = 7,101,692; 10 studies), placenta accreta (OR 2.95, 1.32 to 6.60; n = 705,108; 3 studies), and placental abruption (OR 1.38, 1.27 to 1.49; n = 5,667,160; 6 studies). This is a comprehensive review adhering to a registered protocol, and guidelines for the Meta-analysis of Observational Studies in Epidemiology were followed, but it is based on predominantly observational data, and in some meta-analyses, between-study heterogeneity is high; therefore, causation cannot be inferred and the results should be interpreted with caution.
When compared with vaginal delivery, cesarean delivery is associated with a reduced rate of urinary incontinence and pelvic organ prolapse, but this should be weighed against the association with increased risks for fertility, future pregnancy, and long-term childhood outcomes. This information could be valuable in counselling women on mode of delivery.
剖宫产率在全球范围内持续上升，最近（2016 年）报道的西欧、北美和南美洲的剖宫产率分别为 24.5%、32%和 41%。本系统评价的目的是描述剖宫产对母婴和后续妊娠的长期风险和益处。主要的产妇结局是盆底功能障碍，主要的婴儿结局是哮喘，主要的后续妊娠结局是围产儿死亡。
系统地检索了 Medline、Embase、Cochrane 和 Cumulative Index to Nursing and Allied Health Literature（CINAHL）数据库中发表的人类受试者研究（最后一次检索 2017 年 5 月 25 日），并辅以手动检索。纳入的研究为随机对照试验（RCT）和大型（超过 1000 名参与者）前瞻性队列研究，随访时间超过 1 年，比较了阴道分娩和剖宫产分娩的妇女的结局。两名评估员筛选了 30327 份摘要。两名评估员使用苏格兰校际指南网络（SIGN）方法检查表和非随机研究的偏倚风险评估工具对研究进行了风险评估。当存在显著异质性（I2≥40%）时，结果在固定效应荟萃分析或随机效应模型中进行汇总。纳入了一项 RCT 和 79 项队列研究（均来自高收入国家），共涉及 29928274 名参与者。与阴道分娩相比，剖宫产与尿失禁风险降低相关，比值比（OR）0.56（95%CI 0.47 至 0.66；n=58900；8 项研究）和盆腔器官脱垂（OR 0.29，0.17 至 0.51；n=39208；2 项研究）。剖宫产分娩的儿童在 12 岁前患哮喘的风险增加（OR 1.21，1.11 至 1.32；n=887960；13 项研究）和 5 岁前肥胖的风险增加（OR 1.59，1.33 至 1.90；n=64113；6 项研究）。剖宫产术后妊娠与流产（OR 1.17，1.03 至 1.32；n=151412；4 项研究）和死胎（OR 1.27，1.15 至 1.40；n=703562；8 项研究）的风险增加有关，但与围产期死亡率无关（OR 1.11，0.89 至 1.39；n=91429；2 项研究）。剖宫产术后妊娠与前置胎盘（OR 1.74，1.62 至 1.87；n=7101692；10 项研究）、胎盘植入（OR 2.95，1.32 至 6.60；n=705108；3 项研究）和胎盘早剥（OR 1.38，1.27 至 1.49；n=5667160；6 项研究）的风险增加有关。这是一项全面的综述，遵循已注册的方案，并遵循观察性研究荟萃分析的指南，但它主要基于观察性数据，在一些荟萃分析中，研究之间的异质性很高；因此，不能推断因果关系，结果应谨慎解释。
与阴道分娩相比，剖宫产与尿失禁和盆腔器官脱垂发生率降低相关，但这应与生育力、未来妊娠和长期儿童结局增加的风险相权衡。这些信息在为妇女提供分娩方式咨询时可能很有价值。
