Purpose: Sperm retrieved by testicular sperm extraction is routinely used to attempt pregnancy by in vitro fertilization-intracytoplasmic sperm injection. We evaluated the efficacy of cryopreserving testicular sperm collected by testicular sperm extraction at diagnostic biopsy.
Materials and methods: A total of 73 men with obstructive and 42 with nonobstructive azoospermia underwent testicular sperm extraction at diagnostic biopsy. Sperm was retrieved and cryopreserved in all cases of obstruction and in 15 of nonobstructive azoospermia cases. Before freezing we determined sperm count, motility, morphology and viability, and after thawing we assessed sperm motility and viability. In 17 couples a total of 20 cycles of in vitro fertilization-intracytoplasmic sperm injection were performed and fertilization, cleavage and pregnancy rates were determined in cases of obstruction and nonobstruction.
Results: Sperm count and morphology were lower in the testicular biopsies of men with nonobstructive versus obstructive azoospermia. Motility was low or absent in all testicular sperm extraction specimens. Importantly, pre-freeze (63%) and post-thaw (31%) viability was the same in both patient groups. After in vitro fertilization-intracytoplasmic sperm injection using frozen and thawed testicular sperm the fertilization, cleavage, implantation and clinical pregnancy rates were 60, 86, 16 and 50%, respectively. Using cryopreserved sperm we observed no differences in outcome of any in vitro fertilization-intracytoplasmic sperm injection procedure in patients with obstructive versus nonobstructive azoospermia.
Conclusions: Cryopreservation of testicular sperm provides enough good quality sperm after thawing to result in excellent in vitro fertilization-intracytoplasmic sperm injection outcomes. Cryopreservation does not adversely affect intracytoplasmic sperm injection outcomes, including pregnancy rate. Therefore, we recommend routine testicular sperm extraction and cryopreservation of sperm at testicular biopsy.