Poor outcome with round spermatid injection in azoospermic patients with maturation arrest

Objective: To compare the outcome of intracytoplasmic sperm injection (ICSI ) and round spermatid injection (ROSI), both obtained by testicular sperm e xtraction (TESE), and to compare the results of fresh versus frozen ROSI. Design: Retrospective study. Setting: An IVF unit at a university hospital Patient(s): Eighteen infertile couples with nonobstructive azoospermia. Intervention(s): TESE with ROSI or ICSI of mature spermatozoa into metaphas e II oocytes was performed. The resulting embryos were transferred to femal e partners. The spare round spermatids were frozen. Main Outcome Measure(s): Fertilization and cleavage rates, embryo quality, and clinical pregnancy rates. Result(s): Seventeen ROSI cycles and six ICSI cycles were compared. Fertili zation rate following ROSI (44.9%) was significantly lower than with ICSI ( 69%). A significantly higher rate of cleavage arrest occurred following ROS I (40.8%) as compared to ICSI (8.2%). The morphology of embryos resulting f rom ROSI was significantly pool-rr. No pregnancies were achieved following ROSI as compared to a 50% clinical pregnancy rate in the ICSI group. The fe rtilization and cleavage rates following ROSI with fresh versus frozen-thaw ed spermatids were comparable. Conclusion(s): In azoospermic patients with maturation arrest at the stage of round spermatids the efficiency of ROSI appears to be extremely poor. Th e role of ROSI in the treatment of nonobstructive azoospermia should be ree valuated. (Fertil Steril(R) 2000;74:443-9. (C) 2000 by American Society for Reproductive Medicine.).