There are various types of Genetic Diagnosis available including Preimplantation Genetic Testing for Aneuploidy (PGT-A). Most individuals have 46 chromosomes. Misdivision following fertilization, or a genetically abnormal egg or sperm, can result in an embryo with too many or too few chromosomes. This incorrect number of chromosomes is called “aneuploidy.” The risk of aneuploidy increases with age and includes chromosomal conditions such as Down and Turner Syndrome as well as trisomy 18 and 13, all of which can lead to miscarriage.
PGT-A is currently the only way to determine if an embryo contains an abnormal number of chromosomes prior to pregnancy. This reduces the chance of having a child with a chromosome abnormality (which often causes birth defects and cognitive disabilities), and increases the chance for success of IVF.
Without PGT-A, embryos are selected for transfer based on their morphology (physical appearance and development). It is important to note that just as you cannot judge a book by its cover’, the overall appearance and development of an embryo is not always associated with its chromosomal content. Therefore, a well-developed embryo may be selected for transfer, but may not result in a pregnancy.
RMI offers testing for common chromosome abnormalities, as well as 24-chromosome microarray, the newest technology with the capability to test the entire chromosome complement of a cell. The purpose of PGT-A for aneuploidy is to increase a couple’s chance for pregnancy, to reduce the risk for miscarriage, and to improve the overall chance of bringing home a healthy baby after in vitro fertilization.