The freezing procedure can be performed at the stage of fertilized oocytes, embryos and blastocysts.
Embryo cryopreservation/freezing is achieved using cryoprotectant such as propenediol together with a freezing device and by gradual temperature decreases, untill we reach -196° C .
Embryos are stored in liquid nitrogen and can be preserved for a long time.
During thawing the embryo is gradually returned to 37° C and placed in an incubator for observation until the time of embryo transfer.
Our center has achieved a very satisfying recovery rate of about 80% for embryos who have undergone freeze-thaw.