A new method for freezing testicular biopsy sperm: three pregnancies with sperm extracted from cryopreserved sections of seminiferous tubule.

OBJECTIVE

To determine whether spermatozoa, located in the seminiferous tubules obtained by needle puncture testicular biopsy, could be cryopreserved successfully within the tubules and subsequently be used for in oocyte fertilization via intracytoplasmic sperm injection (ICSI) after the spermatozoa were removed from the thawed tubules.

DESIGN

Clinical case series.

SETTING

Private IVF unit.

PATIENT(S): Six azoospermic patients (four obstructive, two maturation arrest).

MAIN OUTCOME MEASURE(S): Survival rate of thawed spermatozoa, fertilization rate of oocytes after ICSI with spermatozoa extracted from thawed tubules and pregnancies.

RESULT(S): All six patients had adequate motile spermatozoa extracted from the thawed tubule sections, and all patients achieved fertilization via ICSI with their partner's eggs. The fertilization rate was 46%, compared with 56% obtained in other previous patient cycles using fresh testicular spermatozoa. Three pregnancies resulted from five ETs.

CONCLUSION(S): Cryopreservation and subsequent thawing of seminiferous tubules proved to be a simple and successful method for storage of testicular spermatozoa, reducing the need for repetitive testicular biopsies and increasing the likelihood of sperm availability on the day of oocyte retrieval.