EMBRYO VITRIFICATION ON DAY2 AT 4-CELL STAGE USING CRYOLOOP DEVICE: OUR EXPERIENCE.

Vitrification of human embryos using cryoprotectants was established as the method for human embryo cryopreservation. Vitrification using cryotop container kit was advocated by Kuwayama et al as a simple and rapid method of cryopreservation. Vitrification has proved to be a better choice in comparison to slow freezing with higher survival rates of cleavage stage embryos. Embryo vitrificationcan be done at the day2, day3 or day5 at 4-cell, 8-cell and blastocyst stages respectively. Embryo vitrification on day 2 at 4- cell stage using cryoloop device is a practical and proven method of cryostorage of human embryos in an ART programme.