Negative correlation between presence of reactive oxygen species and Sperm Motility Index in whole semen samples of infertile males

Abstract Objective To investigate the relationship between the Sperm Motility Index and the presence of reactive oxygen species in semen. Methods We retrospectively analyzed Sperm Motility Index measured by the Sperm Quality Analyzer and reactive oxygen species levels in 92 semen samples of infertile male patients who visited the Ebina Ladies’ Clinic between September 2011 and June 2012. Using the same semen samples, we also analyzed 8 sperm parameters measured by computer-assisted semen analysis and validated the relationship with the Sperm Motility Index. Results The presence of reactive oxygen species in semen was positive in 19 samples and negative in 73 samples. In the reactive oxygen species-positive group, there was a significant negative correlation between the logarithm of reactive oxygen species level and Sperm Motility Index ( p = 0.039). Conclusions This is the first study to find a significant negative correlation between Sperm Motility Index and reactive oxygen species level. This result indicates that the presence of reactive oxygen species in semen may inhibit the fertilization ability of spermatazoa as measured by the Sperm Motility Index.