The survival rate was 69% for thawed zygotes. Any patient, no matter the amount of time between embryo freezing and thawing, can expect nearly the same potential for success as they experienced with the fresh IVF cycle that the frozen embryos came from. Women 35 years and younger have over a 60 percent chance of pregnancy per transfer If poor quality embryos were frozen, the survival rate after thawing also because the pregnancy rate would be expected to be lower. A second vital factor is that the number of embryos that were transferred. Take the example of a couple who produce four good quality embryos. The most important part about this technique is that the benefit of being able to thaw and transfer back fewer embryos compared to the “slow-freeze” process that was traditionally used, as the embryos frozen via vitrification have higher survival rates through the freeze and unfreeze method. Next Generation freezing method in which we freeze ALL embryos. more than 95th of embryos frozen using this method can survive and cleave after thawing at a later date and one blastocyst will be transferred. For women aged 30–34 using their own eggs, the birth rate per embryo transfer performed was 32.8% for fresh cycles and 27.5% for frozen/thaw cycles. for women aged over 44, it was 2.3% and 6.5% respectively.