Effect of testicular morphology on embryo development to the blastocyst stage after round spermatid injection

If spermatozoa cannot be found after testiculer sperm extraction (TESE) in patients followed up due to nonobstructive azospermia (NOA) and the patients do not want donor spermatozoa, performance of round spermatid injection (ROSI) with the current technology seems to be the last resort. This retrospective study was conducted to evaluate the effect of testicular morphology on the development of embryos to the blastocyst stage obtained from ROSI. Between September 2019 and March 2020, after TESE and biopsy 29 patients who had only spermatid were taken to study. Tubular appearance, basal membrane appearance, Johnson score, peritubular fibrosis, interstitial fibrosis, and Leydig cell proliferation were pathologically examined. Following egg collection, ROSI was applied to the oocytes using the piezoelectric method. The embryos were monitored until the blastocyst stage. The mean age of the 29 patients was 36.3±5.01 years. Also, 7 patients had not previously undergone TESE, 20 had previously undergone once, and 2 had previously undergone twice. It was observed that having a history of TESE and a high Johnson score increased the likelihood of the embryo remaining in the blastocyst stage (P=0.021 and 0.014, respectively). However, other parameters do not affect the likelihood of blastocyst formation (P>0.05). Low TESE history and high Johnson score were associated with embryo development to the blastocyst stage. If spermatozoa are not found in patients with nonobstructive azoospermia, ROSI performed during initial TESE increases the likelihood of blastocyst formation.