Preimplantation genetic testing (PGS or PGT-A) allows the chromosomal content of embryos to be determined before they are transferred to the mother’s uterus, without negatively affecting their development or implantation capacity. Couples must necessarily undergo an in vitro fertilisation (IVF) cycle to generate embryos and be able to perform genetic analysis during their development in vivo. In order to carry out this analysis, an embryo biopsy must be performed, which consists of removing a few cells from the embryo. The result obtained from these cells is extrapolated to the rest of the embryo. Embryos free of chromosomal alterations will be transferred to the mother’s uterus. The clinical pregnancy rate in PGS or PGT-A cycles is around 70-80%.
