How does freezing affect sperm?

Between 50% to 80% of sperm die in the freezing process. Sperm survival varies a great deal from individual to individual and from ejaculate to ejaculate. We prepare a test thaw vial containing a small amount of semen from each stored ejaculate. A week after freezing, we thaw this vial and take a sperm count to determine the sperm survival rate for that ejaculate. (You can call us for test thaw results a week after your initial appointment).