Time-to-Ejaculation and the Quality of Semen Produced by Masturbation at a Clinic

ObjectivesTo investigate the association between the length of time-to-ejaculation and semen parameters.MethodsEjaculates from 142 men under infertility assessment were analyzed according to the World Health Organization guidelines. Seminal neutral α-glucosidase (NAG), prostate-specific antigen (PSA), zinc, and fructose were also measured. Three groups according to the length of the time-to-ejaculation were defined: G<10 (<10 minutes), G10–15 (10 to 15 minutes), and G>15 (greater than 15 minutes).ResultsTime to ejaculation showed negative significant correlation with sperm concentration (rho = −0.20, P = 0.02), total sperm count (rho = −0.20, P = 0.04), NAG (rho = −0.20, P = 0.01), and fructose (rho = −0.30, P = 0.02), respectively. No significant correlations existed among the time-to-ejaculation and age, sexual abstinence, semen volume, sperm motility, PSA, and zinc. There were negative significant associations among time-to-ejaculation and sperm concentration (β = −3.0; P = 0.004), total sperm count (β = −10; P = 0.02), total count of progressive motility (β = −7.0; P = 0.02), and fructose (β = −0.30; P = 0.02), respectively. No significant associations existed among the time-to-ejaculation and semen volume, motility grades, NAG, PSA, and zinc. G<10 was characterized by higher sperm concentration, total sperm count, and total count of progressive motility compared with G10–15 (mean difference = 33 × 106/mL; P = 0.01), (mean difference = 96 × 106/ejaculate; P = 0.50), (mean difference = 77 × 106/ejaculate; P = 0.02), respectively, and G>15 (mean difference = 50 × 106/mL; P = 0.01), (mean difference = 176 × 106/ejaculate; P = 0.02), (mean difference = 110 × 106/ejaculate; P = 0.03), respectively. Fructose was significantly higher in G<10 compared with G>15 (mean difference = 5.0 mmol/L; P = 0.03).ConclusionsThe time-to-ejaculation length was associated with semen parameters. These results might reflect the negative effect of acute stress during semen collection via masturbation at a clinic on semen parameters.