[Are testes in oligo/azoospermia homogenous or heterogenous?].

We determined whether a single testicular specimen is sufficient to represent qualitatively the spermatogenic process within the testes of azoospermic or severely oligospermic infertile men. In 191 testes of azoospermic patients and in 26 of those with severe oligospermia, fine needle aspirations at 3 different sites of each testis were performed. Aspirated material from each puncture was stained and in each smear all spermatogenic cells, as well as Sertoli cells, were identified. Testes were classified according to the most mature spermatogenic cell type present, or the presence of only Sertoli cells. The homogeneity of the testicular spermatogenic process was then evaluated. There was an overall intratesticular difference between aspirates in 14.1% of azoospermic testes and in 26.9% of severely oligospermic testes with regard to the most mature spermatogenic cell type. When spermatozoa were the most mature cell type, they were detected in all of the 3 aspirates in 71.4% of the testes. In 18.4% or 10.2% of this group of testes they were retrieved in only 1 or 2 of the aspirates, respectively. In testes in which spermatids or spermatocytes were the most mature spermatogenic stage, these cell types were detected in all 3 aspirates in only 36.4% and 68.0%, respectively. In azoospermic patients with full testicular spermatogenesis, the likelihood of retrieving spermatozoa from the testes was 84.3%, 92.7% and 100% in 1, 2 and 3 specimens, respectively. The following conclusions were drawn: There is a wide range of testicular heterogeneity in azoospermia or very severe oligospermia for diagnosing the testicular spermatogenic pattern. In azoospermia, specimens from several testicular sites are required. It is strongly recommended that no assisted fertilization be offered to azoospermic patients unless prior evaluation of the spermatogenic pattern in the seminiferous tubules is determined.