The levels of fructose, acid phosphatase, citric acid, zinc, maltase, testosterone, prostaglandin E, putrescine, spermidine and spermine were compared in ejaculates collected by masturbation and after coitus in the same individuals. Coitus was associated with a significantly larger semen volume and increased concentrations and total amounts of prostaglandin E and polyamines in the ejaculate. In contrast, the concentrations of the conventional glandular parameters remained relatively unaffected, although a slight dilution of the seminal vesicle contribution to the ejaculate occurred after coitus. In the majority of cases, ejaculates provided by masturbation were significantly enriched in spermatozoa, but the total contributions under both conditions remained the same. It is concluded that the assessment of semen quality in male individuals using the conventional parameters of accessory gland function can be made with ejaculates provided by masturbation or coitus.