Testicular sperm extraction: impact of testicular histology on outcome, number of biopsies to be performed and optimal time for repetition

Testicular sperm extraction (TESE) may not always be successful in patients with non-obstructive azoospermia, as they only have minute foci of active spermatogenesis from which a tiny number of spermatozoa can be extracted. T he aim of this study was to find the percentile incidence of successful TES E in non-obstructive azoospermia patients in relation to various histopatho logical patterns and the number of performed biopsies, and to determine the optimal time needed for repetition. A total of 216 patients underwent bila teral testicular biopsy taking a single piece from each testis for sperm re trieval and pathological evaluation. In another 100 patients, the same proc edure was done but taking multiple samples (maximum four samples/testis), S permatozoa were successfully retrieved from 37.5 and 49% of patients who su pplied single and multiple samples respectively, TESE was significantly hig her when multiple samples were taken in all histopathological groups except for Sertoli cell-only syndrome, tubular sclerosis and Klinefelter's patter n, Twenty-seven patients underwent repeated TESE for ICSI between 1 and 24 months from the first procedure; all of them had easy sperm retrieval durin g the first procedure. Although sperm retrieval was successful in 75 and 94 .7% of patients who underwent the second attempt, before and after 3 months respectively, a second TESE was usually more difficult and necessitated mu ltiple sampling.