The<unk>  is a method for diagnosing male infertility due to the inability of the sperm to penetrate the ova. Sperm are mixed with<unk>  eggs that have had the outer membranes removed, and the number of sperm penetrations per egg is measured. The human sperm does not fertilize the<unk>  eggs.  Results suggest that men whose sperm fail the<unk>  are three times less fertile than those whose sperm pass.
Hamster test
Triple test
Glucose tolerance test
Simmonds' test
Unterberger test
ACTH stimulation test
Sweat test
Heaf test