PGT-A
Embryonic Genetic Testing Testing the cells of embryos created through IVF allows parents to identify genetic abnormalities or conditions before transfer into the womb. Known as Preimplantation Genetic Testing, PGT is an embryonic procedure done in unison with IVF where a tissue biopsy of a developing embryo is taken and tested for genetic abnormalities. Blastocysts stage embryos are biopsied, usually removing 5-10 cells. The tissue is sent to a third-party genetics lab for analysis. In addition to embryo grading, PGT can help improve your chances of selecting a healthy embryo for transfer, and ultimately, live birth. Carriers of certain genetic diseases are usually healthy individuals and may have no family history of genetic diseases. Most people do not know they are carriers until they have a child born with the disease. In addition to embryo grading, PGT can help improve your chances of selecting a healthy embryo for transfer, and ultimately, live birth.
PGT-M
PGT-SR
AKA PGS
AKA PGD
AKA PGD
Recommended for
All IVF Patients (particularly if female is +35) and those looking to choose the sex of their child
Patients at high-risk of having a child with a specific genetic disease
Patients with a chromosomal rearrangement
Goal
Increase chances of achieving a succesfull pregnancy or having a child of a particular sex
Reduce risk of passing an inherit condition
Screens for specific unbalanced chromosom rearrangements
Genetic test type
Screens for chromosome abnormalities and sex chromosomes
Screens for a specific single gene disorder
Typically no, pending case review
Requires personalized preparation?
No
Yes
Typically no, pending case review
PGT-A: PREIMPLANTATION GENETIC TESTING FOR ANEUPLOIDES Formerly known as PGS (preimplantation genetic screening), PGT-A gives information about the number of chromosomes within IVF embryos. Those with normal results have higher odds of achieving a successful pregnancy. It may also be used to choose the sex of the anticipated child. PGT-A may be added in conjunction with an IVF treatment cycle – the only adjustment from a patient perspective is that the embryos must be frozen to await the test results, requiring a Frozen Embryo Transfer (FET) as opposed to a fresh transfer, which doesn’t impact success rates whatsoever. After receiving the test results and discussing them with you, we choose an embryo and thaw it for your FET.
Potential PGT-A Results There are three potential results that can come from each embryo tested with PGT-A: Euploid (normal), Mosiac (mixed – some cells tested are normal, some are abnormal), and Aneuploid (all cells tested are abnormal). Aneuploidy & Age While everyone is at risk of producing aneuploid embryos, the risk gets higher as women age. Aneuploid embryos are associated with increased implantation failure, miscarriage, and lower live birth results.
PREIMPLANTATION GENETIC TESTING PGT is broken into three main testing categories: •
Preimplantation genetic testing for aneuploidies (PGT-A)
•
Monogenic/single gene defects (PGT-M)
•
Chromosomal structural rearrangements (PGT-SR)
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