Genetic Testing (PGT)
Preimplantation Genetic Testing (PGT) helps identify embryos that have recognizable chromosomal abnormalities prior to transfer to the uterus. PGT can be used for patients of all ages who have unexplained fertility, severe male factor, advanced maternal age and several failed IVF cycles with poor quality embryos. This procedure benefits families who have a known history of certain genetic abnormalities.
DIRM now offers blastocyst biopsy with next-generation sequencing (NGS) to IVF patients. NGS is a new technique that tests embryos for aneuploidy, an abnormal number (not 2) of all 22 chromosomes + sex chromosomes (X or Y). Our highly-trained embryologists can remove or biopsy several cells from a day 5 embryo (blastocyst) for genetic testing.
A blastocyst is comprised of hundreds of cells that have differentiated into an inner cell mass (which will develop into the fetus) and the trophectoderm (which will develop into the placenta). During blastocyst biopsy, a small hole is made in the zona pellucida (the shell surrounding the embryo) and several cells are removed from the trophectoderm for testing. The unharmed biopsied blastocysts are then returned to the incubator.
On the fifth day of embryo development, a single cell is taken from an embryo through an opening made in the shell of the embryo through assisted hatching. The DNA from that single cell is then analyzed for any chromosomal abnormalities.
The major advantage of blastocyst biopsy compared to conventional day 3 embryo biopsy is that more cells are analyzed, and therefore, the testing is thought to be more accurate. Secondly, trophectoderm cells (future placenta) are biopsied and a smaller fraction of the total embryo is biopsied. In addition, many scientists believe that blastocyst biopsy is less stressful than conventional embryo biopsy on day 3 where 1 cell out 8 is removed from the embryo.
A disadvantage of blastocyst biopsy is that not all embryos will develop to the blastocyst stage by day 5 of culture. Therefore, patients who have poor embryo quality and development may not have any embryos to test or ultimately to transfer.
Once received by the genetics laboratory; the analysis usually takes 48-72 hours to complete. The entire process and reporting requires approximately 10-14 days.
You will discuss the results with Dr. Russell at your cycle review consultation. This information will determine your next steps; move forward with Frozen Embryo Transfer (FET) cycle, repeat IVF Stimulation to bank additional embryos, or look into alternative options such as Third Party Reproduction.
PGT for chromosomal aneuploidy (PGT-A, also known as PGS)
This test identifies embryos with the correct number of chromosomes to improve the chances of a successful pregnancy.
When an embryo has extra or missing chromosomes, that’s a condition known as aneuploidy. Most aneuploid embryos do not result in a healthy live birth: many lead to spontaneous miscarriage, some fail to implant in the uterus, and some result in a baby with birth defects, intellectual disability, and/or other health problems. Aneuploidy occurs across all age groups, but after a woman reaches age 35, the proportion of aneuploid embryos increases rapidly.
Who is PGT-A for?
- Women over the age of 35
- Women who have had 1 or more miscarriages
- Women who have been through unsuccessful IVF cycles before
- Women who have had a previous pregnancy with whole chromosome abnormality
- Couples challenged by male factor infertility
- Couples who want to reduce the chance of having twins or other multiple births
- Couples interested in learning the sex of their embryo
PGT-A: One step closer to a healthy pregnancy
When you are going through treatment for infertility, you want to plan for success. That’s why so many families make preimplantation genetic testing for aneuploidy (PGT-A, also known as PGS) a standard part of their IVF treatment plan. Invitae Preimplantation Genetic Testing for Aneuploidy (PGT-A) is advanced testing that can help you find the path to pregnancy.
An important part of IVF
PGT-A is a way of identifying embryos with the correct amount of chromosome material to improve your chances of a successful pregnancy.
When an embryo has extra or missing chromosomes or chromosome segments, that’s a condition known as aneuploidy. Most aneuploid embryos do not result in a healthy live birth: many lead to spontaneous miscarriage, some fail to implant in the uterus, and some result in a baby with birth defects, intellectual disability, and/or other health problems. Aneuploidy occurs across all age groups, but after a woman reaches age 35, the proportion of aneuploid embryos increases rapidly.
PGT for structural chromosome rearrangements/translocations (PGT-SR)
This test evaluates embryos for unbalanced structural chromosome rearrangements (translocations). It is useful when a chromosomal translocation has previously been identified in the family.
Invitae’s PGT-SR also screens for chromosomal aneuploidy.
PGT-SR cases are accepted on a case-by-case basis. A referral form and documentation of the known translocation (karyotype) must be submitted, reviewed, and approved by the Invitae Clinical Team to determine eligibility prior to testing.