Corion Fertility Clinic

Vitrification & Frozen Embryo Transfer


Corion runs a very successful Cryopreservation Program. The success rates achieved are similar to the fresh transfer cycle rates. This has only been possible due the latest method of an ultra-rapid flash-freezing protocol called Vitrification where a very high concentration of cryoprotectant is used. The embryos / oocytes are plunged directly into the liquid Nitrogen. The result is a solid glass-like cell, free of ice crystals. Vitrification cools the cells in an extraordinarily faster speed greater than 15.000º C per minute so that there is no time for ice crystals to be formed, but instead a kind of gel appears leaving the cells undamaged. In the classical freezing method, embryos were slowly cooled at a rate of 0´3º degrees per minute in order to avoid ice crystal formation around & within the cells.

At Corion, we cryopreserve all our embryos & oocytes by Vitrification method only. This is because Vitrification offers improved survival rate of the embryos as well as oocytes as compared to classical slow freezing method. This results in better rates of implantation & pregnancy. To check our success rate of Frozen Embryo Transfers kindly check our webpage on Success Rates

Frozen Embryo Transfer

When planning a Frozen Embryo Transfer (FET), the endometrium of the uterus is prepared through oral medication. The frozen embryos are thawed the day before the planned embryo transfer or on the same day depending on whether it is a Day 3 Embryo or Day 5 Embryo. We also perform Laser Assisted Hatching on thawed embryos just prior to embryo transfer to increase the Implantation Rate. The pregnancy rate of Frozen Embryo Transfers at our clinic is approximately 40-45%. Our clinic runs a successful Cryo-shipper Program and we can help you ship your embryos to us. This facility however, is currently only for shipments within India, as per our DGFT rules. For more information related to Frozen Embryo transfer, you can write an email to us at