Extended Culture and Blastocyst Transfer

After fertilisation, the oocytes are put in a specific culture medium where they can grow. The embryologist can examine the quality of the embryos by watching their growth, symmetry, and fragmentation (and hence the chance of a successful pregnancy). Compared to a day three embryo, culturing blastocysts (day five of embryo development) allows embryologists to choose embryos that are more likely to be euploid (have the correct number of chromosomes) and hence have a better likelihood of clinical pregnancy and live birth.

It happens because the embryos that will become blastocysts show us that they have better potential than the rest to go ahead and give the desired result. The embryologist will choose the best blastocyst for embryo transfer. If there are good-quality embryos left over after the embryo transfer, then we can freeze them if the couple wishes. Each treatment is unique. The embryologists, in collaboration with the doctor, are next to the couple to decide which will be for the case the day of the embryo transfer that will give the best result.