Blastocyst development after assisted reproduction using spermatozoa obtained after testicular stem cell transplantation in mice.

BACKGROUND Since its introduction in 1994, testicular stem cell transplantation (TSCT) has been widely used for research. This technique may also become important for preserving fertility in pre-pubertal cancer patients. Therefore, it is necessary to investigate the safety aspects of reproduction using spermatozoa obtained after TSCT. In this study, preimplantation development of mouse embryos, using spermatozoa obtained after TSCT, was examined. METHODS TSCT-derived spermatozoa were used for IVF and ICSI. Embryos were cultured for five days until they reached blastocyst stage and were evaluated by differential staining. RESULTS IVF revealed significantly lower fertilization and development rates after TSCT-IVF compared to control-IVF. Blastocysts derived from TSCT-IVF had significantly lower inner cell mass numbers (ICMs) and lower ICM/trophectoderm (TE) ratios compared to control-IVF blastocysts. No differences in fertilization and development rates were observed between TSCT-ICSI and control-ICSI, and blastocyst quality in the transplanted group was similar to that of the control blastocysts. CONCLUSION Our study showed that after TSCT-IVF, fertilization and preimplantation development were disturbed and blastocysts showed reduced ICM and ICM/TE ratio. However, after TSCT-ICSI, both fertilization and preimplantation development were normal and blastocyst formation was comparable to control-ICSI.