Liu Y, et al. - This study sought to select biomarkers that could assess sperm quality. Researchers examined semen samples in 172 fertile males; multivariate logistic regression analysis revealed that the levels of COX1 (17.5 ng/ml) in seminal plasma may represent a useful biomarker for sperm quality. Investigation showed that the values of parameters related to sperm quality varied significantly between COX1 level ≥ 17.5 ng/ml group and COX1 level < 17.5 ng/ml group. Additional investigation of two consecutive semen samples from 48 participants showed that the first semen samples had a higher sperm concentration and a larger proportion of spermatozoa displaying progressive motility, a lower rate of sperm DNA fragmentation and a lower proportion of spermatozoa undergoing the acrosome reaction spontaneously; identical outcomes were seen for the second semen samples. The results demonstrated that COX1 could be utilized as an indicator of sperm status and may be effective for distinguishing better quality spermatozoa for artificial insemination.