Male Factor Infertility and Risk of Multiple Sclerosis (MS): A Systematic Review and Meta-Analysis

Objective: Multiple sclerosis is an autoimmune disease of central nervous system (CNS). There are a few articles studying the risk factors of developing MS in men. Male infertility can stem from a range of etiological factors such as genetics or environment. In the context of MS, research suggests a potential link, possibly due to shared immunological and inflammatory mechanisms. Therefore, we designed this study to evaluate the relationship between male infertility and MS development. Materials and methods: We systematically searched PubMed, Embase, Scopus, web of science, Google scholar and gray literature including references of the references as well as conference papers which were published up to June 2021. The search strategy in PubMed was ("Infertility, Male"[Mesh] OR [Male Infertility] OR [Sterility, Male] OR [Male Sterility] OR [Subfertility, Male] OR [Male Subfertility] OR [Sub-Fertility, Male] OR [Male Sub-Fertility] OR [Sub Fertility, Male]) AND ("Multiple Sclerosis"[Mesh] OR [Sclerosis, Multiple] OR [Sclerosis, disseminated] OR [Disseminated Sclerosis] OR [MS] OR [Multiple Sclerosis, Acute Fulminating]) AND ("Testicular Diseases"[Mesh] OR [Disease, Testicular] OR [Diseases, Testicular] OR [Testicular Disease]) AND ("Multiple Sclerosis"[Mesh] OR [Sclerosis, Multiple] OR [Sclerosis, disseminated] OR [Disseminated Sclerosis] OR [Multiple Sclerosis, Acute Fulminating] OR [MS]). Results: The literature search revealed 197 articles, after deleting duplicates 109 remained. For the meta-analysis, 3 studies were included. Totally, 2090 MS cases as well as 3895562 healthy subjects were enrolled. One hundred and fourteen infertile men were in MS group and 139716 infertile men were in controls. The pooled OR for male factor infertility and odds of developing MS was1.87 (95% CI: 0.89-3.94) (I2=86.1%, P=0.001). Conclusion: The results of this systematic review and meta-analysis show that there is no relationship between male factor infertility and risk of MS.