At What Age Threshold does the Decline in Semen Parameters Begin?

OBJECTIVE  To analyse changes in semen parameters according to different age groups in men presenting to an infertility clinic, and determine the age threshold for decline in semen quality. STUDY DESIGN Observational study. PLACE AND DURATION OF STUDY Andrology Laboratory, Department of Urology, Kahramanmaras Sutcu Imam University, Turkey, from January 2018 to December 2019. METHODOLOGY Semen analysis records of infertile men, who were referred to Andrology Laboratory, were retrospectively evaluated. The age groups were categorised as 20-29, 30-34, 35-39, 40-44, and 45-55 years. Each group was completed to 100 semen samples retrospectively and sequentially without any preferences. The differences of semen parameters between age groups were analysed with the one-way ANOVA test. Linear relationship was checked by ANOVA. RESULTS The mean age of 500 patients was 37.18 ± 8.11 years. While no linear relationship was observed in semen volume, concentration, and total sperm count with age (p=0.133, p=0.290 and p=0.261, respectively). A linear decline was observed in progressive motility, vitality, and morphology parameters with advancing age (all, p<0.001). In linear contrast analysis according to the 20-29 age group; significant decline in progressive sperm motility, morphology, and vitality started and continued in the 35-39 age group (all, p<0.001). CONCLUSION With advancing age, a significant linear decrease in sperm motility, morphology and vitality was observed in infertile men. This significant decline in sperm motility, morphology and vitality continues at age 35 and over. Therefore, infertile men who plan to postpone paternity should consider the age factor. Key Words: Aging, infertility, Paternal age, Semen analysis, Sperm.