Effect of ejaculation on prostate-specific antigen levels in normal men.

While several manipulations such as digital rectal examination and cystoscopy have been shown to increase prostate-specific antigen (PSA) levels, lack of ejaculation for a period of time has been implicated as a cause of decreased serum PSA concentrations. However, the effect of ejaculation on the serum PSA concentration is not clear. This work determined the effect of ejaculation on serum PSA levels in normal men. Blood samples of 19 healthy subjects were taken before and 5 consecutive days after ejaculation. One subject was withdrawn from the study because of ejaculation during sleep, since another ejaculation was prohibited during the study. The mean PSA levels of the men before and 5 consecutive days after ejaculation were 0.79, 0.72, 0.63, 1.01, 0.71, and 0.74 ng/ml--not statistically significantly different. We conclude that ejaculation does not seem to affect the serum PSA concentration.