Preimplantation Genetic testing (PGD / PGS)
Preimplantation genetic testing is a state of the art procedure used in conjunction with in- vitro fertilization (IVF) to screen embryos for the appropriate number of chromosomes (pre-implantation screening; PGS) or for a specific genetic abnormality such as cystic fibrosis (pre-implantation genetic diagnosis [PGD] testing). These genetic conditions can interfere with embryo implantation, result in pregnancy loss, or in the birth of a child with physical problems, developmental delay or mental retardation.
PGD is performed in conjunction with an in-vitro fertilization cycle where multiple eggs are produced, retrieved from the ovaries and fertilized with sperm in the IVF laboratory. Several days after egg retrieval, cells are removed from each embryo through a procedure called embryo biopsy. These cells are shipped to an outside laboratory and analyzed.
Reproductive Resource Center of Greater Kansas City offers PGD screening for chromosome disorders and single gene defects. Testing may be recommended by your physician when there is a possibility, indicated by your medical history or advanced maternal age, or that your embryos could be affected by a genetic disease. PGD testing can only be performed within the context of an IVF cycle where eggs and sperm, united in the laboratory, develop into embryos.
Potential Indications for PGD
- Inherited genetic disorders
- Recurrent Miscarriage
- Advanced Maternal Age
- Unexplained Infertility
- Unsuccessful IVF Cycles
Genetic testing of the embryo may reduce the potential for adverse pregnancy outcomes for couples “at risk” by enabling us to test the embryos for certain genetic abnormalities before they are chosen for transfer back to the woman. For example: 4 embryos resulted from an IVF cycle and through PGD testing, 2 were identified as genetically abnormal and 2 were normal. Armed with this knowledge, only the normal embryos would be selected for embryo transfer thereby potentially reducing the possibility of miscarriage or birth defects.
It is important to remember that PGS and PGD are considered screening tests. Please, discuss in detail the risks, benefits, and alternatives to this testing option with your physician.