World-Class Embryo Testing

Preimplantation Genetic Testing (PGT) is the screening of an embryo for chromosomal and genetic abnormalities and disorders. During IVF, a few cells from the embryo’s outer ridge (that later develop into the placenta) can be carefully removed. This is usually conducted on Day 5 or 6 of development when the embryos have reached what’s called the “blastocyst” stage. After the biopsy is safely performed, the embryos are then frozen while the sampled cells are analyzed for chromosomal or genetic issues.

There are three types of genetic abnormalities: 

• PGT-A identifies aneuploidy, the term used to describe any embryo with either too many or too few chromosomes (or large extra or missing pieces of chromosomes). One form of aneuploidy causes Down syndrome, and other chromosomal changes may cause up to 60% of miscarriages or prevent pregnancy altogether.
• PGT-M tests for monogenic, or single gene disorders, such as Cystic Fibrosis, Huntington’s disease, muscular dystrophy, and hemophilia – detection that is especially important for people who know their families carry the defective gene.
• PGT-SR looks for structural rearrangements, when a parent is known to carry a chromosome change such as a translocation or inversion. These can cause extra or missing chromosomal material in embryos.

In short, yes! Embryo testing via PGT can decrease your chance of miscarriage by detecting chromosomal abnormalities - a common cause of miscarriage. Studies have shown dramatic decreases in miscarriage rates in IVF when PGT-A is performed as part of the process.

Because PGT-M and PGT-SR look at specific genetic markers, the benefit of those tests is that a fertility team can avoid an unwanted disorder. A baby can be born without the specific genetic condition or chromosome rearrangement seen in family members.

Because PGT-A leads to fewer miscarriages, it can be combined with another procedure called Elective Single Embryo transfer (e-SET), so that a single embryo can be transferred during IVF. 

Physicians suggest e-SET with the knowledge that they are transferring the most chromosomally fit embryo, therefore eliminating the need to transfer multiple, unscreened embryos with the hope that one will be healthy enough to create a successful pregnancy and a healthy baby.

In short, with PGT-A, you and your medical team can be more confident about the success of a single embryo transfer.

Overall, embryo testing is considered safe with no known increase in the associated risk of birth defects or genetic disorders. The biopsied cells are removed from the outer ridge of the embryo that ultimately becomes the placenta (not the fetus), which limits the risks.

Also, these same cells can be used for PGT-A, PGT-M, and PTG-SR. That said, there is always a slight chance that removing the cells from the trophectoderm could damage or disrupt the embryo. The risk of this is said to be less than 1%.

At Illume Fertility, your doctor, genetic counselor, and medical support team will discuss all options with you and help you choose the path most likely to result in a healthy baby.