Which is more successful “Day 3” or “Day 5” Embryo transfers?
An embryo begins its growth as a single cell, and then divides every 12-24 hours. By Day 3, it is about 4-8 cells, and it is referred to as a multicell embryo. During the early growth of the multicell embryo, all of the energy and chemicals required for cell division come from the mother’s egg. By Day 5, the embryo, now called a blastocyst, is about 70-100 cells.
In-vitro techniques are routinely transferred to the uterus on day 2 or 3 when they are at the 4–8-cell stage. The implantation rates of these embryos are disappointingly low and range between 10 and 20%. The standard treatment is to transfer more than one embryo into the uterus to obtain a reasonable pregnancy rate. This results in a high order of multiple pregnancies and twins with increased pregnancy complications such as abortion and premature deliveries.
It has been suggested that transferring embryos at the blastocyst stage instead of selection at an earlier stage without knowing their developmental capability might enhance the implantation rate by a better embryo selection, thereby reducing the need to transfer more embryos. Under current culture conditions, embryo developmental arrest occurs around the 8-cell stage and formation of the blastocyst is uncommon.
We Aashakiran IVF always want happy faces of our patients with successful results. So, we also prefer day 5 blastocyst transfers to increase the chances of pregnancy. This will decrease the chances of multiple pregnancies. This is the one of the reason we have highest success rate.