First report in Uruguay on vitrification of embryos as a real alternative to slow freezing
Keywords:
CRYOPRESERVATION, VITRIFICATIONAbstract
Introduction: vitrification is a cryopreservation technique that forms part of the so called "fast" cryopreservation techniques. Compared to traditional slow freezing processes, vitrification enables the total elimination of both intracellular and extracellular crystal formation.
It allows for placing the cells directly on the cryoprotector and submersing them in liquid nitrogen. Its application around the world has exponentially grown and the technique may be applied both to ovocytes and embryos at all stages.
Objectives: to carry out a review of the vitrification technique, the first one to be conducted in Uruguay, and to present the two-year experience at the Ibero-American Center for Assisted Reproduction.
Method: we included 17 patients in our study, the embryos of which have been vitrified and unvitrified. We used the commercial Cryotop method with the Kitazato vitrification solutions.
Results: with an average of 2,71 (±0,69) vitrified embryos per patients, global embryo survival rate after vitrification was 93,4%. With an average of 2,41 (±0,62) embryos transferred , the final pregnancy rate was 47,1%. The average age of patients who succeeded in getting pregnant is lower (average 30,0 ±2,51) than those who fail to get pregnant.
Conclusions: vitrification as a cryopreservation method appears to be a promising technique and seems to be a good substitute for show freezing technique, due to its high-success rates, its reliability and execution speed, with replicable results.
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