What can be observed two days after in Vitro Fertilisation?

Forty-eight hours after IVF, the first embryos can be observed. As in people, no two of them are alike. Each embryo has its own features and, at this stage, it can already be divided into 2, 3, 4 or 5 cells. Not all embryos show the same quality even in the same cycle.

We can consider that a good embryo is the one that on the second day has 4 cells of equal size, with fragmentation percentages not higher than 10-15%.

However, there are embryos that suddenly, the second or third day make one of their cells disappear, for example, going from four to three cells and then continue dividing themselves, as if nothing had happened. Until now, this fact was considered anomalous, but a study by Institut Marquès has shown that embryos that have reabsorbed some of their own cells and then continue to divide up to blastocyst (the early stage of embryonic development, which appears between the 5th and 6th day after fertilisation) have the same rate of implantation, evolving pregnancy and of healthy born child.

Presented at the ESHRE

The study, developed at Institut Marquès and presented at the Congress of the European Society of Human Reproduction and Embriology (ESHRE), has shown that embryos have the capacity to self-repair from their second day of life.

This discovery has been possible thanks to the Embryoscope, an embryo incubator that incorporates a video camera that records their development. In IVF fertilisation treatments, embryos are classified according to guidelines based on their appearance and how they develop. In this way, those that are considered with a better prognosis are transferred to the patient for implantation and further evolution.