Received October 10, 2012
Accepted November 28, 2012

To evaluate the effects of re-vitrification of embryos, we studied the feasibility, development and blastocyst formation in mouse embryos after 3 successive vitrifications in stages 2, 4 and 8 cells, respectively. We used the RapidWarmTM and RapidVitTM Cleave kits from Vitrolife ®, with the CryoLoopTM technique. The survival rates, cleavage rates and blastocyst formation rates of mouse embryos that were vitrified three times, were compared with the rates of mouse embryos that were frozen only once, and with the information reported in the literature. The final survival, cleavage and blastocyst formation rates obtained were: 97.5%, 100% and 88.89%, respectively in the re-vitrified embryos. The results suggest that the re-vitrification of embryos is a safe technique that can be done without affecting the survival, cleavage and development to blastocysts.