Abstract
Mobile phone use has become ubiquitous in modern life, raising public concern over its potential effects on male reproductive health. While several observational studies have reported associations between prolonged phone use and decreased sperm quality or testosterone levels, these findings remain inconclusive due to residual confounding, reverse causation, and inconsistent exposure measurement. We conducted a two-sample Mendelian randomization (MR) analysis using genetic variants associated with mobile phone usage duration to investigate its causal effects on male fertility. Inverse variance weighting (IVW) was employed as the primary analytical method. Genetic predisposition to longer mobile phone use was not associated with levels of sex hormone-binding globulin (SHBG), total testosterone, or the risk of abnormal sperm parameters, erectile dysfunction, or testicular dysfunction. These null findings were consistent across all MR methods and sensitivity analyses. Our findings suggest that mobile phone use is unlikely to have a direct causal impact on male reproductive hormones or sexual function. Future research incorporating precise exposure measurements and mechanistic evaluations is warranted.