PGS & PGD
A Guide to PGS/PGD at RAD
What is Pre-Implantation Genetic testing?
Traditionally, the embryo selection process for an IVF cycle is based solely on an embryo’s phenotype (the physical appearance). However a physically normal embryo is not necessarily an indication of the genotype (the genetic composition). Because an embryo that appears healthy can contain genetic mutations or chromosomal abnormalities, pre-implantation genetic screening and testing can provide insight into the genetic and chromosomal health of the embryo. At RAD we offer both Pre-Implantation Genetic Diagnosis (PGD), and Pre-implantation Genetic Screening (PGS). These tests can greatly enhance the outcomes of embryo selection for an IVF cycle and increase the chances of a healthy pregnancy. Determining whether or not to pursue testing depends on a variety of factors, and is both a personal and medical decision.
What is PGD?
Pre-Implantation Genetic Diagnosis is performed on cell(s) that are atraumatically removed from an embryo 5 or 6 days after fertilization to test for a particular inherited genetic disease. These tests provide our IVF experts with the unique and specific genetic make-up of each embryo, allowing our team to choose the embryo with the lowest risk of genetic mutations and greatest chance for a healthy pregnancy.
When to consider PGD?
Couples who are carriers of inherited genetic diseases can consider PGD testing to increase the chances of a healthy embryo selection. PGD tests for diseases such as
- Sickle cell anemia
- Huntington’s disease
- Cystic Fibrosis
What if I don’t know if I am a carrier?
As part of RAD’s routine initial patient work up, you will be tested for certain genetic mutations, in order to enact an appropriate line of care. If either partner is a carrier for a specific genetic mutation, PGD offers the most appropriate solutions to identify those embryos that lack the particular genetic disease mutation.
What is PGS?
Pre-Implantation Genetic Screening (PGS), also known as “Aneuploidy Screening,” tests biopsied cells for any chromosomal abnormalities within the embryo. Our IVF lab experts look at the embryo’s chromosomal “copy number” for any indications of irregularities. Sometimes an embryo may have an extra chromosome – such as the case with Trisomy 21 or Down’s Syndrome. This condition is called an aneuploidy. When a chromosome is missing, it is called a “monosomy.” When there is an extra chromosome, this is termed “trisomy.”
When to consider PGS:
Patients who have experienced the following might consider PGS:
- Recurrent spontaneous loss of pregnancy
- Previous pregnancy loss
- Multiple failed IVF Cycles
- Advanced maternal age
- Male factor infertility
Can I have both PGD and PGS testing performed?
Yes, patients whose embryos undergo PGD testing can also undergo PGS testing to further ensure the health of their embryos. PGD testing can eliminate any embryos that pose a risk for inherited genetic diseases. PGS testing can then be utilized to determine if any of the “healthy” PGD tested embryos show signs of any chromosomal abnormalities or copy number irregularities.
Why PGS and PGD at RAD is Unique:
At RAD we utilize a unique and highly technical method of PGS and PGD testing. Traditionally, many fertility laboratories perform testing on day 3 of the embryo formation because it allows for an easier extraction of the cells. However this poses some risk, such as injury to surrounding cells, or the extraction of a cell that does not provide a complete picture of the genetic composition of the embryo. At RAD, we perform a more technically challenging test by extracting the cells on the 5th day of development. Not only does this allow us to analyze multiple cells, providing a more precise measurement of the genetic components of the embryo, but it also lowers the risk of embryo damage. This sensitive testing provides patients with a greater chance for a successful pregnancy and sets RAD apart as an advanced center in fertility technologies.
