Preimplantation Genetic Diagnosis (PGD) is an advanced genetic testing procedure used during In Vitro Fertilization (IVF) to identify genetic or chromosomal abnormalities in embryos before they are transferred to the uterus.

During the IVF process, once the embryos reach a certain stage of development, a few cells are carefully removed from each embryo. These cells are then tested for specific genetic conditions such as cystic fibrosis, thalassemia, sickle cell anemia, or chromosomal disorders like Down syndrome. Only healthy embryos without the identified conditions are selected for implantation.