Pre-implantation genetic testing, or PGT, is of mainly three different types, and includes the following:

• Pre-implantation genetic testing for aneuploidy (PGT-A)
  This screening test focuses on screening the embryos for certain chromosomal abnormalities known as aneuploidy. PGT-A helps in the identification of chromosomally normal embryos, which increases the chances of successful implantation. It also reduces the risk of miscarriages.
  
  
• Pre-implantation genetic testing for monogenic disorders (PGT-M)
  Pre-implantation genetic testing for monogenic disorders is used during in vitro fertilization (IVF) to screen embryos for specific genetic conditions or disorders before they are implanted into the uterus. The screening process is performed when a patient has an increased risk for a specific genetic condition in their embryos.
  
  
• Pre-implantation genetic testing for structural rearrangements (PGT-SR)
  This screening is done when a patient or their partner has a rearrangement of their chromosomes, like a translocation or inversion. These disorders are caused by mutations or abnormalities in a single gene and can lead to various inherited conditions, such as cystic fibrosis and sickle cell anaemia.