The role of estrogen receptor-beta gene +1730G/A polymorphisms in recurrent pregnancy loss: A protocol for systematic review and meta-analysis

OBJECTIVE: To identify the role of estrogen receptor-beta (ER-β) gene +1730G/A (rs4986938) polymorphisms in recurrent pregnancy loss (RPL). METHODS: All relevant case-control studies will be systematically searched in multiple databases including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Internet (CNKI), Wanfang and Cqvip. Both pooled odds rations (ORs) and 95% confidence intervals (CIs) will be used to assess the association between ER-β gene +1730G/A polymorphisms and RPL risk. The publication bias will be evaluated using Egger test. RESULTS: ER-β gene +1730G/A variation may be associated with a higher risk of RPL in Caucasian population. CONCLUSIONS: The findings of this meta-analysis will provide high-quality evidence for the association between ER-β gene +1730G/A polymorphisms and RPL, facilitating clinical practice and further scientific studies. OSF REGISTRATION NUMBER: 10.17605/OSF.IO/EW9FB.