Oocyte penetration and acrosome reactions of human sperms. II: Correlation with other seminal parameters

Washed sperm suspensions of fertile men and men consulting for infertility were evaluated for their ability to penetrate zona-free hamster eggs and for their ability to exhibit an acrosome reaction in vitro. Furthermore, the swelling of the spermatozoa under hypoosmotic conditions as indication of their membrane integrity was determined. In the group of fertile men and in the group of patients with normal spermiogram, significantly more acrosome reactions were observed than in the group of infertile men with abnormal spermiogram parameters (p less than 0.05). This difference was still more significant when men with a positive hamster penetration test (H.O.P. test) and men with a negative H.O.P. test were compared (p less than 0.005). However, within the groups the level of acrosome reactions after incubation appeared to be highly variable. In a second series of experiments, working with semen obtained during our in vitro fertilization program, we found that the fertilization of human ova does not seem to be dependent on a strong progress of the acrosome reaction. Finally, swelling of the spermatozoa in a hypoosmotic medium was weakly correlated (r = 0.70, p less than 0.01; n = 73) with trypan blue exclusion. No significant correlations with other semen parameters, hamster ova test included, were found.