Reproductive capacity of round spermatids compared with mature spermatozoain a population of azoospermic men

The present study aims to evaluate the injection of testicular round sperma tids from patients with complete failure of spermiogenesis compared with th at of mature epididymal and testicular spermatozoa, Over a period of 8 mont hs, 188 azoospermic patients were evaluated with a view to their inclusion in our intracytoplasmic sperm injection (ICSI) programme. All patients had had a previous testicular biopsy; 38 had pure obstructive azoospermia, whil e 150 had non-obstructive azoospermia, Mature spermatozoa were found in 93 patients, whereas spermatozoa were entirely absent, with a predominance of round spermatids in 87, In eight patients, spermatids could not be found an d therefore their cycles were cancelled. There was an early appearance of t he two pronuclei stage in the round spermatid group compared with the matur e spermatozoa group of patients (10.2 and 16 h respectively). The fertiliza tion rate was also significantly lower (P = 0.00001) in the round spermatid group. The numbers of embryos developed and of embryo transfers in the rou nd spermatid injection group were significantly lower compared with the mat ure spermatozoa injection group (P = 0.05 and 0.0001 respectively). No preg nancies resulted from round spermatid injection, while 18 pregnancies were achieved from the injection of mature spermatozoa, In conclusion, injection of round spermatids from patients with complete failure of spermiogenesis resulted in a significantly lower fertilization rate and a higher developme ntal arrest compared with injection of mature spermatozoa, With no pregnanc ies achieved, one may question the unusual variability of reported success rates and stress the need for further research in order to improve the outc ome of this novel technique.