Comparison of semen quality in older and younger men attending an andrology clinic

The effects of age on semen quality were analysed in patients referred to an andrology outpatient clinic in a retrospective study covering a period of 3 years. Semen analyses of older men (n = 66; > or = 50 years; median: 53) were compared with those of young patients (n = 134; 21-25 years; median 24). The duration of sexual abstinence was longer among older patients (median: 5.5 vs. 5.0 days; + 10%, P < 0.05). Even after adjustment for duration of sexual abstinence, progressive motility (- 27%, P < 0.01), percentage of morphologically normal spermatozoa (- 44%, P < 0.01) and semen volume (- 29%, P < 0.0005) were significantly lower in older than in younger men. Impaired sperm morphology was mainly attributed to abnormal staining of flagella (+ 50%, P < 0.05) and an increased portion of coiled or bent tails (+ 44%, P = 0.001) indicating epididymal dysfunction. Total sperm count and sperm concentration were unaffected by age. Age-dependent changes in accessory gland function, as indicated by fructose concentration (- 27%, P < 0.05), was correlated with lower semen volume. Moreover, serum testosterone levels were significantly reduced in the group of older men (median: 3.0 vs. 3.6 ng ml-1; -17%, P < 0.005).