An important advance in Human Reproduction was the development of advanced technologies for the genetic diagnosis of the preimplantation embryo. These studies can be carried out at different stages of embryonic development, although more recently they have been carried out at the Blastocyst stage (day 5/6 of development). At this stage, a biopsy of what will be the trophectoderm is performed. The sample will be studied while the embryo will be cryopreserved until the result is obtained.

PGT-A: studies chromosome aneuploidies
PGT-M: monosomy diseases
PGT-SR: segmental diseases

It involves studying the DNA in the embryonic culture medium to fundamentally determine chromosomal aneuploidies. It is a technology that is developing rapidly and would imply being able to genetically study the embryo before implanting it without having to biopsy.