Pre-implantation Genetic Testing (PGT) is a method to diagnose chromosomal or single gene abnormalities so that embryos affected can be identified and excluded from being transferred in the uterus, so that only non-affected embryos are allowed to establish a pregnancy.

The female partner of the couple undergoing PGT needs to have ovarian stimulation and egg collection as done in the classical IVF. The collected eggs then are injected with single spermatozoa so that embryos are formed.

Once embryos are available, they are allowed to grow to the blastocyst stage at which point they contain a big number of cells. A biopsy of the blastocyst under the microscope is done and cells are sent for genetic investigation that include the Pre-implantation Genetic Diagnosis (PGD) also known as PGT M/SR and the Pre-implantation Genetic Screening (PGS) also known as PGT A.