Maternal complications and cesarean section without indication: systematic review and meta-analysis

ABSTRACT OBJECTIVE The objective of this study was to determine the risks of severe acute maternal complications associated with cesarean section without medical indication. METHODS A systematic review was carried out with meta-analysis. The literature search was performed systematically, in multiple stages, in the PubMed, Lilacs, and Web of Science databases using the following descriptors: (postpartum period) and (cesarean section or natural childbirth) and ((morbidity or mortality) or (postpartum hemorrhage) or (puerperal infection) or (surgical infection) or (puerperal disorders)). The protocol of the study was registered at PROSPERO as CRD42016032933. A total of 1,328 articles were found; after selection, eight publications that met the study objective and inclusion criteria were selected, with information on 1,051,543 individuals. RESULTS The results obtained in the meta-analyses indicate that women with cesarean section have a higher chance of maternal death (OR = 3.10, 95%CI 1.92–5.00) and postpartum infection (OR = 2.83, 95%CI, 1.585.06), but they have a lower chance of hemorrhage (OR = 0.52, 95%CI 0.48–0.57). For the blood transfusion outcome, the group effect was not associated with the type of delivery (95%CI 0.88–2.81). CONCLUSIONS The quality of evidence was considered low for hemorrhage and blood transfusion and moderate for postpartum infection and maternal death. Thus, cesarean sections should be performed with caution and safety, especially when its benefits outweigh the risks of a surgical procedure.

摘要
研究目的：本研究旨在明确无医学指征剖宫产（cesarean section）相关的严重急性孕产妇并发症风险。
研究方法：本研究采用系统评价结合荟萃分析的研究设计。通过多阶段系统检索PubMed、Lilacs及Web of Science数据库，检索式采用如下主题词组合：（产后期）且（剖宫产或自然分娩）且（发病或死亡）或（产后出血）或（产褥感染）或（手术部位感染）或（产褥期疾病）。本研究方案已在PROSPERO平台注册，注册号为CRD42016032933。最终共检索到1328篇文献，经筛选后纳入符合研究目的与纳入标准的8项研究，涉及研究对象共计1051543名。
研究结果：荟萃分析结果显示，剖宫产产妇的孕产妇死亡风险（比值比OR=3.10，95%置信区间CI：1.92~5.00）与产后感染风险（OR=2.83，95%CI：1.58~5.06）均显著升高，但产后出血风险更低（OR=0.52，95%CI：0.48~0.57）。针对输血结局，组间效应与分娩方式无显著关联（95%CI：0.88~2.81）。
研究结论：本研究证据质量分级为：产后出血与输血相关证据质量较低，产褥感染与孕产妇死亡相关证据质量中等。因此，剖宫产手术应秉持谨慎与安全原则开展，尤其当手术收益大于外科操作本身风险时。