reactive oxygen species (ros) level in seminal plasma of infertile men and healthy donors

background: reactive oxygen species (ros) are a group of free radicals that in excessive amounts have negative influence on sperm quality and function. objective: we compared ros levels in seminal plasma of infertile men with this level in healthy donors. we also determined the ros level in semen of infertile men according to the etiology of infertility, and also the effect of smoking on its level. materials and methods: in total, 63 infertile patients and 63 healthy donors as control were selected. complete physical examination, semen analysis, scrotal sonography and hormone assay were done for all patients. azoospermic patients were excluded from the study. ros level in semen was measured by chemiluminescence assay in both groups. patients also were divided in two groups according to the etiology of infertility. results: the mean age of normal subjects and infertile men were 30.78±3.73 years and 31.43±6.60 years respectively. the mean ros level in normal men was 180.05 rlu (relative light unit), while this was 1852.04 rlu in infertile patients, which is significantly higher in case group (p=0.000). fifty patients had varicocele and in 13 patients no specific etiology was found. the mean ros level in varicocele patients was 2215.42 rlu and in unknown group was 454.44 rlu (p=0.048). conclusion: our study showed that the level of ros in seminal fluid of infertile men is significantly higher than fertile donors and also in infertile patients with varicocele it is higher than patients with unknown cause.