Impacts of COVID-19 and SARS-CoV-2 on male reproductive function: a systematic review and meta-analysis protocol

INTRODUCTION: COVID-19 pandemic caused by SARS-CoV-2 has become a global health challenge. SARS-CoV-2 can infect host cells via the ACE2 receptor, which is widely expressed in the corpus cavernosum, testis and male reproductive tract, and participates in erection, spermatogenesis and androgen metabolism. Also, the immune response and persistent fever resulting from COVID-19 may lead to damage of the testicular activity, consequently compromising male fertility. METHODS AND ANALYSIS: PubMed, MEDLINE, EMBASE, Web of Science, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal database, Chinese Biomedical Databases and Wanfang Data will be systematically searched for observational studies (case–control and cohort) published up to March 2021 in English or in Chinese literature on the impacts of COVID-19 and SARS-CoV-2 on male reproductive function. This protocol will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines and Meta-analysis of Observational Studies in Epidemiology. The primary outcome will be semen parameters, and the additional outcomes will include: (a) detection of SARS-COV-2 in semen, (b) male sexual hormones, (c) sperm DNA fragmentation index, (d) erectile function, (e) evaluation of testis and also the male genital tract. Two reviewers will independently extract data from the included studies based on a predesigned data extraction form. The risk of bias of included studies will be evaluated through the Newcastle-Ottawa Scale for observational studies. Review Manager software V.5.3 will be used for statistical analysis. Q statistic and I² test will be performed to assess the heterogeneity among studies. Sensitivity analysis will be used to explore the robustness of pooled effects. We will use the Grading of Recommendations Assessment, Development and Evaluation system to assess the quality of evidence. ETHICS AND DISSEMINATION: Ethical approval is not required and results will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42021245161.