Longitudinal study of semen quality of unexposed workers: seminal plasma characteristics.
Schrader-SM; Breitenstein-M; Turner-TW; Simon-SD
Comparative Spermatology 20 Years After 1991 Jan; 75:905-908
A study of longitudinal changes in seminal plasma composition of unexposed workers was conducted. Monthly semen samples were collected by masturbation from 45 men, 25 to 35 years old, for 9 months (mo). None had ever had a fertility problem or been exposed to known reproductive toxicants. Semen volumes were measured. The plasma was separated off and analyzed for pH, osmolality, glycerylphosphorylcholine (GPC), fructose, and zinc. Analysis of the data showed that between subject variability accounted for more than 50% of the variance for volume, osmolality, and fructose and zinc concentrations. Within subject variability explained more than 60% of the variance in pH and GPC concentration. The authors conclude that the fructose and zinc concentrations show a high level of repeatability, both having intraclass correlations (Rls) above 70%. This means that a single measurement of zinc or fructose concentration would provide a good representation of a subject's mean level of these parameters. Several measurements of GPC may be needed in order to obtain a true representation of an individual's true mean level. The Rls of the remaining parameters lie somewhere between these extremes.
Epidemiology; Reproductive-system; Body-fluids; Biochemical-indicators; Chemical-composition; Humans
Comparative Spermatology 20 Years After