Abstract
BACKGROUND: Sleep quality has been increasingly recognized as an important determinant of overall health, yet its influence on male fertility remains underexplored. This study investigated the association between male sleep quality and reproductive outcomes, including semen characteristics, hormone profiles, and partner pregnancy success, in infertile couples. RESULTS: A total of 727 male partners from infertile couples were evaluated between October 2023 and February 2025. Sleep quality was assessed using Pittsburgh Sleep Quality Index and categorized as good or poor. Poor sleep quality was reported in 75.1 percent of participants. Men with poor sleep quality showed significantly lower sperm concentration (β = -1.39, 95% confidence interval = -2.11 to -0.67, p < 0.001), reduced progressive motility (β = -1.25, 95% confidence interval = -1.61 to -0.88, p < 0.001), and decreased total motility compared with those reporting good sleep. No significant associations were observed between sleep quality and hormone concentrations, including follicle-stimulating hormone, luteinizing hormone, estradiol, prolactin, and testosterone. Poor male sleep quality was also linked to a lower probability of achieving clinical pregnancy (odds ratio = 4.67, 95% confidence interval = 3.08 to 7.09, p < 0.0001). CONCLUSIONS: Poor male sleep quality is associated with impaired semen quality and reduced chances of pregnancy in couples with infertility. These findings highlight the potential value of improving sleep as a modifiable factor to enhance male reproductive health and fertility outcomes.