ABSTRACT
Cryopreservation of testicular spermatozoa remains a commonly used and vital technique in assisted reproduction. There are several reasons for this, many of which relate to the unique treatment dilemmas posed by patients with NOA. First, the chance of unsuccessful sperm retrieval in a patient with NOA is approximately 30% (4). Obviously, an unsuccessful biopsy makes the effort undertaken by the couple to coordinate ovarian hyperstimulation and oocyte retrieval completely wasted. However, there is no way to predict the likelihood of this occurrence. Cryopreservation allows the couple to time oocyte retrieval to their convenience and only in the event of successful testis sperm extraction. Second, without cryopreservation, the couple is forced to undergo repeated testis biopsies for each desired cycle of IVF-ICSI. This assumes that couples will need repeated cycles due to: (i) failure of attempted cycles and (ii) desire for multiple children. Both these occurrences are common; if patients with NOA were required to undergo fresh testis biopsy every time they planned to undergo an IVF-ICSI cycle, there would be a far higher likelihood of failure at each cycle (again a 30% risk of unsuccessful biopsy). In addition, there is signifi cant injury to the testis incurred with each sperm extraction (5). This injury is compounded by the fact that both androgen production and spermatogenesis are often already impaired in the patient with NOA. Taken together, these reasons help illustrate why cryopreservation of testicular sperm is so crucially important to patients with NOA.
