Investigating the association between caesarean section (SC) and childhood asthma has shown contradictory results in different studies. The present study was conducted to determine the association between SC and childhood asthma. The present study was conducted based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. All the steps of the study were conducted independently by two reviewers from the inception until February 1, 2019. In case of disagreement, the third reviewer resolved it. We searched international online databases, including Scopus, Cochrane Library, PubMed/Medline, Embase, Web of Science (ISI), Science Direct, and Google scholar. The results of studies were combined using random effects model, and heterogeneity was measured through I2 index and Cochran’s Q test. Comprehensive Meta-Analysis Software was used for meta-analysis. The significance level of all tests was considered to be P < 0.05. The heterogeneity rate was high (I2 = 67.31%, P < 0.001) in 37 studies. The results showed that SC increased the risk of childhood asthma (RR (relative risk) = 1.20 [95% CI 1.15–1.25, P < 0.001]). The association between emergency and elective SC and childhood asthma was significant with RR of 1.18 (95% CI 1.07–1.29, P < 0.001) in 13 studies and 1.23 (95% CI 1.20–1.26, P < 0.001) in 13 studies, respectively. The subgroup analysis for RR of childhood asthma in SC indicated that study design (P = 0.306), prospective/retrospective studies (P = 0.470), quality of studies (P = 0.514), continent (P = 0.757), age of diagnosis (P = 0.283) and year of publication (P = 0.185) were not effective in the heterogeneity of studies. Sensitivity analysis by removing one study at a time indicated that the overall estimate is robust. According to the meta-analysis, SC (overall, elective, and emergency) increased the risk of childhood asthma. Therefore, it is hoped that developing clinical guidelines and implementing appropriate management plans would diminish the risk of asthma.

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剖宫产与儿童哮喘之间的关联：更新的系统评价和荟萃分析

调查剖宫产 (SC) 与儿童哮喘之间的关联在不同的研究中显示出相互矛盾的结果。本研究旨在确定 SC 与儿童哮喘之间的关联。本研究是根据系统评价和荟萃分析 (PRISMA) 指南的首选报告项目进行的。从开始到2019年2月1日，研究的所有步骤均由两名审稿人独立进行。如有分歧，由第三名审稿人解决。我们搜索了国际在线数据库，包括 Scopus、Cochrane 图书馆、PubMed/Medline、Embase、Web of Science (ISI)、Science Direct 和 Google 学者。研究结果采用随机效应模型进行组合，异质性通过I2指数和Cochran Q检验进行测量。综合荟萃分析软件用于荟萃分析。所有测试的显着性水平被认为是P <0.05。37 项研究的异质性很高（I2 = 67.31%，P < 0.001）。结果表明，SC 增加了儿童哮喘的风险（RR（相对风险）= 1.20 [95% CI 1.15–1.25，P < 0.001]）。急诊和择期 SC 与儿童哮喘之间的相关性显着，13 项研究的 RR 为 1.18（95% CI 1.07-1.29，P < 0.001），13 项研究的 RR 分别为 1.23（95% CI 1.20-1.26，P < 0.001） . SC儿童哮喘RR的亚组分析表明，研究设计（P = 0.306）、前瞻性/回顾性研究（P = 0.470）、研究质量（P = 0.514）、大陆（P = 0.757）、诊断年龄（ P = 0.283）和出版年份（P = 0。185）对研究的异质性无效。通过一次删除一项研究进行的敏感性分析表明，总体估计是稳健的。根据荟萃分析，SC（总体、选择性和紧急）增加了儿童哮喘的风险。因此，希望制定临床指南和实施适当的管理计划能够降低哮喘的风险。