For women who experience infertility or recurrent pregnancy loss, chromosomal abnormalities in an embryo may be a contributing factor.
As many as 70% of all embryos created naturally are inferior and do not survive the first months of pregnancy. Many are unable to successfully implant (after undergoing IVF) due to these abnormalities or specific genetic conditions.
Preimplantation genetic testing (an advanced embryo biopsy) speaks directly to these significant statistics and is one of the most important breakthroughs in the history of reproductive medicine.
GENETIC TESTING 101
Performed during an IVF cycle, preimplantation genetic testing allows our physicians and laboratory team to identify genetic or chromosomal defects in an embryo prior to being used in an IVF cycle.
The resulting high-quality, chromosomally-normal embryos that we select will then have the best chance of implanting successfully in the uterus and later developing into a healthy baby.
Boston IVF offers two different types of genetic tests for embryo evaluation: preimplantation genetic screening (PGT-A) and preimplantation genetic diagnosis (PGT-M). These tests were formerly named, preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS).
HOW IT HELPS
- with the help of PGT-A, we can identify the cause of recurrent pregnancy losses or unsuccessful fertility cycles, select the very the best embryos prior to implantation, and increase your IVF success rate.
- with the help of PGT-M, we can establish whether you and your partner are at risk of having a baby with a specific genetic disease and eliminate the chance of passing it on to your children.
- the option of performing PGT-A and PGT-M on the same embryo biopsy is also available and can improve healthy live birth rates.
As women age, a higher proportion of their embryos are genetically abnormal.
This higher rate of genetically abnormal embryos (aneuploidy) is the primary contributor to the increased chance of unsuccessful IVF cycles and recurrent miscarriage in older women.
It is important to note, however, that while aneuploidy is more common as you get older, all pregnancies are at risk for a chromosome abnormality.
WHAT WE KNOW
Chromosome "makeup" is a major contributing factor to experiencing a successful pregnancy.
Transferring embryos without major chromosome abnormalities through preimplantation genetic testing for aneuploidies (PGT-A) increases pregnancy success and promotes the birth of healthy babies. PGT-A was formerly known as PGS, preimplantation genetic screening.
WHAT IS PGT-A?
PGT-A is a laboratory test we offer that helps our doctors identify chromosomal-normal embryos for transfer to the uterus. It reveals chromosomal abnormalities that often lead to unsuccessful fertility cycles and instances of miscarriage.
Testing involves the removal of one or more cells from embryos before they are transferred during IVF, where they are genetically tested in our laboratory. If the cells are found to have an abnormal chromosome number, then the embryo is less likely to implant properly.
PGT-A allows us to screen and select the most viable embryos for embryo transfer. In turn, it leads to higher fertility success rates and reduces the rate of miscarriage and unsuccessful IVF cycles.
WHEN TO CONSIDER PGT-A
- women with age-related infertility
- women experiencing unsuccessful cycles
- women with unexplained IVF failures
- women experiencing multiple miscarriages
- male factor infertility
Benefits Of PGT-A
- increases fertility success rates
- reduces miscarriage rates
- reduces the risk of unsuccessful IVF cycles
- aids in identifying chromosomally normal embryos
- increases the chance of successful embryo implantation
- reduces the need for multiple IVF cycles
- 98% accuracy in detecting major chromosome abnormalities
PGS: FAST FACTS
- approximately 50% of miscarriages occur due to chromosomal abnormalities
- in the case of miscarriages, 68% of embryos are chromosomally abnormal. Embryos that are chromosomally normal are more likely to result in live birth
- some chromosomal abnormalities impair the embryo’s ability to implant in the uterus
- embryos that are chromosomally normal have a better chance of successful implantation
- male factor infertility (including abnormal quantity and quality of sperm) can increase the risk of chromosomal abnormalities in the embryo
- PGT-A can be used to diagnose Down Syndrome
- if you decide to add PGS to your treatment plan, please be sure to discuss it with your Financial Coordinator, as often times there are additional out-of-pocket costs involved
PGT-A & Advanced Age
Yes. As women age, the risk of chromosomal and genetic abnormalities increases. This leads to a lower chance of pregnancy and a higher risk of miscarriage. Abnormal embryos that create a pregnancy may result in a miscarriage or a baby with a chromosome disorder.
If you're close to or over the age of forty, have had multiple miscarriages, or been through several unsuccessful IVF cycles, PGT-A is an extremely accurate test to determine whether your embryos are healthy prior to implantation.
PGT-A Reduces miscarriage
Yes. In IVF cycles that do not include PGT-A, embryos are chosen primarily on their visual quality – which cannot distinguish chromosomally normal embryos from abnormal ones. IVF cycles that do include PGT-A enable the identification of embryos with normal chromosomes and are more likely to result in a pregnancy that leads to a healthy baby.
Preimplantation genetic testing for monogenic/single gene defects (PGT-M) is a genetic test that is performed on an IVF embryo (prior to transfer) that identifies the presence of a specific genetic mutation.
While PGT-M is not necessary for all patients, it is an invaluable service for those who may be carriers of a genetic disease.
The primary benefit of PGT-M is to substantially reduce the risk of passing inherited conditions on to subsequent children. It aides in the identification and diagnosis of genetic abnormalities that may lead to disease during or after a baby's birth.
By avoiding the transfer of affected embryos, patients can ensure that children resulting from IVF are free of the disease.
PGT-M, or preimplantation genetic testing for monogenic/single gene defects was formerly known as PGD, preimplantation genetic diagnosis.
HOW DOES PGT-M WORK?
PGT-M testing occurs after fertilization and before the embryo transfer to the woman's uterus during IVF. It involves obtaining genetic material (a small number of cells) from an embryo and examining its genetic makeup.
From this very small sample, we are able to test and screen embryos for a specific genetic abnormality.
PGT-M: FAST FACTS
- has a 98% accuracy rate in detecting major chromosome abnormalities
- is indicated for couples at higher risk of having a child with a specific single gene disorder
- can now be performed for most known single gene disorders.
- increases pregnancy success and promotes the birth of healthy babies
- if you decide to add PGT-M (formerly PGD) to your treatment plan, please be sure to discuss it with your Financial Coordinator, as often times there are additional out-of-pocket costs involved
WHAT DOES PGT-M SCREEN FOR?
Our collaborating laboratories have extensive experience with PGT-M and have analyzed more than 250 different single gene disorders.
Its purpose is to aide in the identification and diagnosis of genetic abnormalities that may lead to disease during or after your baby's birth. It reduces the chances of conceiving a child with a genetic factor and increases your chance of carrying and delivering a healthy baby.
PGT-M can identify many genetic disorders, including:
- Cystic Fibrosis
- Fragile-X syndrome
- Spinal Muscular Atrophy
- Huntington's disease
- Autosomal dominant polycystic kidney disease
- Becker's muscular dystrophy
- Beta thalassemia
- Charcot-Marie-Tooth disease 1A
- Muscular dystrophy
- Familiar amyloid polyneuropathy
- Hemophilia A (F8)
- Hemophilia B (F9)
- Multiple endocrine neoplasia, type 2A
- Myotonic dystrophy (Steinert's disease)
- RhD incompatability
- Spinal muscular atrophy