Michelle Emblenton, a biochemist at inviTRA, tells us if the process for embryo transfer is the same whether the embryos are fresh or vitrified:
Is it the same process for fresh and frozen embryos? Basically, the embryo transfer process is the same. The differences are in the preparation. If undergoing a fresh embryo transfer, you will have had your ovarian stimulation and an egg retrieval surgery (which has required a lot more hormonal medication to get to that stage). Following fertilization, the eggs are cultured before programming the embryo transfer.
While the embryos are being developed and cultured, your endometrium will be being prepared for the embryo transfer to be successful. If you are using frozen embryos, perhaps from a previous IVF cycle, you do not need to undergo all the ovarian stimulation and egg retrieval procedure. In fact, the only hormonal medication you will need are the estrogens and progesterone required to prepare your endometrium to be receptive. When your endometrium is ready and the embryos are thored and ready, the embryo transfer will take place. The number of embryos that will be transferred in a fresh embryo transfer or a frozen embryo transfer do not depend on whether they are fresh or frozen, but actually on the quality of the embryos themselves, the age of the recipient woman and any other factors involved with previous IVF treatments or the reasons for infertility itself.
