Preimplantation genetic testing (PGT) is a pair of twin procedures that check for genetic defects in embryos created through in vitro fertilisation (IVF) technology. The PGT umbrella is composed of preimplantation genetic screening (PGS) and preimplantation genetic diagnosis(PGD)
PGS is a method that screens embryos of chromosomally normal genetic parents, for structural or numerical chromosomal anomalies.
PGD is performed to trace potential embryonic defects in couples where one or both partners have a known genetic abnormality. The procedure is capable of detecting sex-linked disorders, single gene defects and chromosomal disorders.
PGT works like a sieve, eliminating embryos that carry unfavourable chromosomal properties. It is especially useful for couples who want to prevent existing genetic conditions from being passed on.
Genetic testing is commonly favoured over conventional post-conception diagnostic procedures which often entail difficult decision making surrounding potential pregnancy termination.