title: Time-to-ejaculation and the quality of semen produced by masturbation at a clinic.
abstract: OBJECTIVE
  To investigate the association between the length of time-to-ejaculation and semen parameters.
  
  
  METHODS
  Ejaculates from 142 men under infertility assessment were analyzed according to the World Health Organization guidelines. Seminal neutral alpha-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), G(10-15) (10 to 15 minutes), and G(>15) (greater than 15 minutes).
  
  
  RESULTS
  Time 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 (beta = -3.0; P = 0.004), total sperm count (beta = -10; P = 0.02), total count of progressive motility (beta = -7.0; P = 0.02), and fructose (beta = -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 G(10-15) (mean difference = 33 x 10(6)/mL; P = 0.01), (mean difference = 96 x 10(6)/ejaculate; P = 0.50), (mean difference = 77 x 10(6)/ejaculate; P = 0.02), respectively, and G(>15) (mean difference = 50 x 10(6)/mL; P = 0.01), (mean difference = 176 x 10(6)/ejaculate; P = 0.02), (mean difference = 110 x 10(6)/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).
  
  
  CONCLUSIONS
  The 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.
authors: Centre of Reproductive Medicine, Scanian Andrology Centre, Malmö University Hospital, Lund University, Malmö, Sweden. saad.elzanaty@med.lu.se
authors: Saad
authors: S
authors: Elzanaty
mesh_terms: D000328:Adult; D004542:Ejaculation; D006801:Humans; D008297:Male; D008418:Masturbation; D008875:Middle Aged; D013076:Sperm Count; D013081:Sperm Motility; D013997:Time Factors