BACKGROUND Since the placenta also has a sex, fetal sex-specific differences in the occurrence of placenta-mediated complications could exist. OBJECTIVE To determine the association of fetal sex with multiple maternal pregnancy complications. SEARCH STRATEGY Six electronic databases Ovid MEDLINE, EMBASE, Cochrane Central, Web-of-Science, PubMed, and Google Scholar were systematically searched to identify eligible studies. Reference lists of the included studies and contact with experts were also used for identification of studies. SELECTION CRITERIA Observational studies that assessed fetal sex and the presence of maternal pregnancy complications within singleton pregnancies. DATA COLLECTION AND ANALYSES Data were extracted by 2 independent reviewers using a predesigned data collection form. MAIN RESULTS From 6522 original references, 74 studies were selected, including over 12,5 million women. Male fetal sex was associated with term pre-eclampsia (pooled OR 1.07 [95%CI 1.06 to 1.09]) and gestational diabetes (pooled OR 1.04 [1.02 to 1.07]). All other pregnancy complications (i.e., gestational hypertension, total pre-eclampsia, eclampsia, placental abruption, and post-partum hemorrhage) tended to be associated with male fetal sex, except for preterm pre-eclampsia, which was more associated with female fetal sex. Overall quality of the included studies was good. Between-study heterogeneity was high due to differences in study population and outcome definition. CONCLUSION This meta-analysis suggests that the occurrence of pregnancy complications differ according to fetal sex with a higher cardiovascular and metabolic load for the mother in the presence of a male fetus. FUNDING None.

中文翻译：

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胎儿性别和孕产妇结局：系统评价和荟萃分析。

背景技术由于胎盘也具有性别，因此在胎盘介导的并发症发生中可能存在胎儿性别特异性差异。目的确定胎儿性别与多种孕产妇妊娠并发症的关系。搜索策略对六个电子数据库Ovid MEDLINE，EMBASE，Cochrane Central，科学网络，PubMed和Google Scholar进行了系统搜索，以鉴定合格的研究。所包括研究的参考清单以及与专家的联系也被用于鉴定研究。选择标准观察性研究评估了单胎妊娠中的胎儿性别和母体妊娠并发症的存在。数据收集和分析数据是由2位独立的审阅者使用预先设计的数据收集表提取的。主要结果从6522篇原始参考文献中，选择了74项研究，包括1,250万妇女。男性胎儿性别与足月先兆子痫（合并OR 1.07 [95％CI 1.06至1.09]）和妊娠糖尿病（合并OR 1.04 [1.02 1.07]）相关。除早产先兆子痫外，其他所有妊娠并发症（即妊娠高血压，子痫前期，子痫，胎盘早剥和产后出血）均与男性胎儿有关，而早产先兆子痫与女性胎儿有关。 。纳入研究的总体质量良好。由于研究人群和结果定义的差异，研究之间的异质性很高。结论这项荟萃分析表明，在胎儿存在性别的情况下，妊娠并发症的发生因胎儿而异，而在男性胎儿的情况下，母亲的心血管和代谢负荷较高。