When will the Embryo Transfer be Done?
After egg collection, embryos with microinjection followed by fertilization are followed and embryo transfer is planned at the appropriate date. Every day, a large number of data can be obtained, such as the number of cells of embryos, the relationship and proportion of cells with each other, whether there are residues between cells. Meanwhile, the environment where the embryos are kept is very similar to the intrauterine tissue in which it will later be inserted into the uterus and creates as much natural environment as possible.
The main goal in embryo transfer is to transfer the best embryo to the intrauterine tissue. At this point, the question arises as to how many healthy eggs can be obtained in collecting eggs and how many healthy embryos can be obtained after fertilization and division stages pass. If the number of eggs is limited or one or two embryos can be obtained, the transfer decision can be made on the 2nd or 3rd day. Placing these 6-8 cell embryos into their natural environment as soon as possible can create a healthier environment for the embryo from time to time.
Another possibility is the 5th day transfer. The embryo that has reached the 5th day is called a blastocyst and contains more than 120 cells. Even the cells that will form the embryo and placenta within the blastocyst have been identified individually. If the aim is to transfer the best embryo, it will be possible to choose from when there are enough embryos in the hand. After fertilization, the structure of the nuclei of cells, the ratio of cells to each other, the number of cells and the presence of intercellular residues means that the blastocyst presence will be the best implanted at the end of these five days since the limited number of embryos are transferred, the use of the best embryo at hand will increase the success of pregnancy. Implantation success in blastocyst transfer is 70%. This rate varies depending on the quality of the embryo on the 2nd and 3rd days, but it is around 40%.
Another important detail about pregnancy health makes blastocyst transfer meaningful. Whether the embryo is healthy depends on its genetic and metabolic status. The embryo that reaches the 5th day and contains a large number of healthy cells is much less likely to have a genetic abnormality.
In order to overcome the problems related to embryo quality in recurrent pregnancy failures, blastocyst transfer offers a much better solution.
If a frozen embryo will remain after our IVF trial, it will be more convenient to store embryos that have reached the blastocyst stage. Because it is possible to have a higher probability of pregnancy after embryo dissolution and transfer.