精子からみた問題点 - とくに精液検査の正常値と妊孕力の評価に関する検討 -

Abstract

妊孕力を有する正常男性群57名と不妊男性群67名について, 種々の精子パラメータを比較した.濃度, 運動率, 総数, 総運動数, 平均運動速度, 正常形態率および透明帯除去ハムスター卵を用いた侵入試験(SPA)における侵入率は, 両群間に有意差を認めた.しかし両群の各パラメータの測定値が両群の鑑別にすべて有用というわけではない.正常値の各パラメータの95%特異性閾値における不妊診断率の比較では, 侵入率が72.4%で最も良好で, ついで運動率, 平均運動速度の順に良好であったが, 濃度の不妊診断率は36.8%と低かった.SPAは妊孕力を最もよく反映し, 不妊治療上, 有力なマーカーとなりうる.また正常群の95%特異性閾値は, 精子濃度24.9×106/ml, 精子運動率34.9%, 正常形態精子率55%で, これらを正常限界値と考える

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.