Chapter 7 Human Epididymal and Testicular Sperm Cryopreservation

Since the advent of intracytoplasmic sperm injection (ICSI) in the early 1990s, surgical techniques to recover samples from the epididymis and testis directly have been used to benefit patients suffering from obstructive and nonobstructive azoospermia. Various studies have demonstrated comparable fertilization, ongoing pregnancy, and implantation rates when fresh and frozen-thawed epididymal sperms were used for ICSI [1]. Injection of fresh and frozen testicular sperms into mature oocytes resulted in similar fertilization rates in cases of obstructive azoospermia. However, in cases of nonobstructive azoospermia, the outcome depends upon the degree of impairment of spermatogenesis, criteria for sperm freezing, and patient selection [2].