The role of seminal oxidation-reduction potential in male infertility: systematic review and meta-analysis.

This systematic review/meta-analysis was conducted using MEDLINE, CENTRAL, Embase and randomized controlled trial registries up to December 2024. The study evaluated whether seminal oxidation-reduction potential (ORP), as a marker of oxidative stress, differs between fertile men and men with infertility, and whether it is associated with semen quality. Thirteen studies were included in the meta-analysis, showing lower ORP levels in fertile men compared with men with infertility [(weighted mean difference (WMD) -4.07, 95% CI -5.80 to -2.35], and in patients with normal semen parameters compared with patients with at least one abnormal semen parameter (WMD -2.39, 95% CI -4.01 to -0.76). Patients with high ORP levels had a lower sperm concentration (WMD -35.76, 95% CI -52.40 to -19.11), total sperm count (WMD -126.41, 95% CI -208.59 to -44.22), total motility (WMD -8.80, 95% CI -11.17 to -6.44), progressive motility (WMD -7.62, 95% CI -10.74 to -4.49) and percentage of normal morphology (WMD -1.55, 95% CI -1.93 to -1.16); and a higher proportion of immotile spermatozoa (WMD +8.46, 95% CI +1.67 to +15.26) compared with patients with low ORP levels. In conclusion, seminal ORP levels are negatively associated with male fertility, sperm concentration, total sperm count, total and progressive motility, and normal morphology; and positively associated with immotile spermatozoa.