Description

Preimplantation genetic testing, also known as embryo biopsy, is used to identify chromosomal or genetic defects in embryos prior to an in vitro fertilization (IVF) cycle. Genetic defects are a primary cause of both the failure of an embryo to implant and subsequent miscarriage after successful implantation. There are two types of genetic tests available for embryo evaluation: Preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS). PGD is used to diagnose a specific, single genetic defect that is known to be carried by one or both parents. This can be because the parent has that defect, such as muscular dystrophy, or because it is present in one of their families’ histories. If PGD identifies an embryo with that genetic defect that risks a child with that disease, the embryo is not selected for implantation in the uterus, and a non-affected embryo is used instead.