What is PGT?
Recently, I had the pleasure of joining a panel on preimplantation genetic testing (PGT) with Drs. Klipstein, Hirshfeld-Cytron and a genetic counselor, Zameena Lakhani from the Chicago Coalition for Family Building. It was a fantastic opportunity to discuss the potential and advancements in PGT for those on a fertility journey.
What is Preimplantation Genetic Testing?
Preimplantation genetic testing is a process used in IVF to examine an embryo's genetics before implantation. One of the primary goals is to check the embryo's chromosome count, as a typical cell in the human body contains 46 chromosomes. If an embryo also has 46 chromosomes, it has about a 50-60% chance of resulting in a live birth. However, if there’s an abnormal number, known as aneuploidy, it’s less likely that the embryo will successfully implant or lead to a full-term pregnancy. When aneuploid embryos do implant, they often result in miscarriage.
Why Consider Genetic Testing?
There are several reasons to consider genetic testing for embryos. Some families may have concerns about specific genetic conditions that could be passed down. For example, if one or both parents are carriers of a condition like sickle cell disease, PGT can test embryos for that condition, allowing the parents to decide if they want to move forward with a particular embryo.
Other Types of Genetic Testing
Beyond chromosome count, PGT can detect rare chromosomal rearrangements or structural issues in embryos. Emerging technologies are even allowing us to explore testing for complex conditions influenced by multiple genes and environmental factors, such as heart disease or diabetes. However, testing for these polygenic conditions also raises ethical considerations that are being carefully weighed in the field.
Exciting Advances Ahead
PGT continues to evolve, and there’s a lot to look forward to as technology advances. From improved testing accuracy to new ways to screen for health risks, the future of PGT holds incredible potential for families embarking on the IVF journey.
