Semen quality and infertility status can be identified through measures of oxidation-reduction potential.

Standard analyses for evaluating semen quality require technical expertise and are interpretive in nature. Oxidative stress (OS) alters many of the semen parameters; thus, a measure of OS could be an indicator of semen quality. Static oxidation-reduction potential (sORP) is a universal measure of OS traditionally used in environmental applications but is increasingly used in biomedical studies. sORP was measured to determine how well it associates with semen quality and if it differentiates semen from infertile patients and fertile donors. All study participants (Infertile, n = 365 and Fertile, n = 50) underwent standard semen analyses, and sORP was measured in unprocessed semen. In infertile patients, sORP increased with decreased total sperm number, motility and morphology. sORP values were higher in samples with abnormal quality (low number, motility and/or normal morphology) compared with those of normal quality. Infertile patients had higher sOPR values compared to fertile donors. A sORP cut-off value of 1.38 mV/106  sperm/ml can differentiate normal from abnormal semen samples, while a cut-off value of 1.41 mV/106 sperm/ml, can differentiate between infertile and fertile semen samples. In conclusion, sORP provides a quick and unbiased indicator of semen quality that can be a beneficial addition to semen analysis to determine semen quality and fertility status.