[Problems in evaluating male fertility: valuable factors in evaluating male fertility and normal values of seminal parameters].

To determine the valuable factor for evaluating male fertility, a comparative study was done as to various seminal parameters between fertile and infertile groups. The fertile group consists of 57 proven fertile males and the infertile group consists of randomly chosen 67 infertile patients. Seminal parameters assessed were sperm concentration, motility, mean velocity, total sperm output, total motile sperm output, sperm morphology, acrosin activity and sperm penetration rate on zona-free hamster egg penetration assay (SPA). The infertile group was significantly different from the fertile group in every parameter except acrosin activity. However, the range of each parameter in the two groups overlapped each other. The diagnostic rate of each parameter, which is the percentage of an infertile male correctly diagnosed as infertile, was calculated by using 95% specificity threshold value of fertile males. The 95% specificity threshold values of sperm concentration, motility and % normal shaped sperm were 24.9 x 10(6)/ml, 34.9% and 55%, respectively, and they could be acceptable for the normal limit of seminal parameters. The diagnostic rate was highest in penetration rate (72.4%). In other words, penetration rate is the most valuable factor in various parameters for making a distinction between fertile and infertile males. Sperm motility and mean velocity showed the next highest diagnostic rate. On the other hand, sperm concentration showed a poor diagnostic rate (36.8%). In addition, there was no significant correlation between penetration rate and any other seminal parameters. These results suggest that the SPA will be an essential test for evaluating male fertility and penetration rate may be a marker of male fertility in the treatment of male infertility.