Embryo Development
The expected action of the embryo is to progress, increasing the number of cells every day. Embryos, which initially develop slowly and then accelerate or initially develop rapidly and then decelerate, mean that they have lost the quality.
They should develop in a standard speed and continuously. Some embryos may completely stop their development (arrest) and may restart dividing 1 day and 2 days later. But these embryos also do not have the desired structure. At the same time, the cells in the embryo (blastomer) should be equal to each other and clear. Curly, cauliflower-like structures in the embryo impair the quality.
It is normal for embryos to stop development a little, develop slowly or even stop during post-fertilization controls. Therefore, the number of embryos with a healthy progress will decrease day by day as long as they are kept in the laboratory.
First, those with bad quality and then those with moderate quality are started to be eliminated. Thus, the embryos with best quality developed for that month remain at the end.
That is why the chance of pregnancy is higher in the 5th, 6th day embryo transfer, called blastocyst transfer. But proceeding until the 5th day would not make sense in a woman with 2-3 oocytes. Because when the embryos are eliminated, an embryo to be transferred may not be left.
