Pre-Implantation Genetic Testing (PGT)

Pre-Implantation Genetic Testing is done in conjunction with an IVF cycle to ensure only genetically normal embryos will be selected to transfer into the uterus for implantation. With PGT, one or two cells are taken from the embryo on Day 3 or 5 and assessed for chromosomal defects that may lead to miscarriages or genetic disorders. This embryo screening technique has many benefits, including:

• Boost the success rates of pregnancy and live birth with IVF treatment
• Reduce the rate of miscarriage
• Reduce the risk of the embryo inheriting a genetic disease
• Only normal embryos will be transferred to the mother’s womb

There are 2 types of genetic tests which are used to identify genetic flaws in embryos, which are Pre-Implantation Genetic Testing for Aneuploidy (PGT-A) and Pre-Implantation Genetic Testing for Monogenic Diseases (PGT-M).

Pre-Implantation Genetic Testing for Aneuploidy, previously known as Pre-implantation Genetic Screening (PGS). PGT-A works as to identify embryos with the correct number of chromosomes which is 46 chromosomes. The benefit of doing this testing is to improve IVF implantation rates and reduce miscarriage rates. This testing is highly recommended for the couples:
•Are of advanced maternal age (above 37)
•Couples with history of recurrent pregnancy loss
•Couples with repeated IVF failure
•Male partner with severe male factor infertility

PGT-A could test diseases such as Down Syndrome (Trisomy 21), Patau Syndrome (Trisomy 13), Edward Syndrome (Trisomy 18), Turner Syndrome (XO), Klinefelter Syndrome (XXY), Triple X syndrome (XXX), Jacob’s Syndrome (XYY).

PGT-A is a routine procedure readily available in TMC Fertility for all patients.

Pre-Implantation Genetic Testing for Monogenic Diseases also previously known as Pre-Implantation Genetic Diagnosis (PGD). This testing is done to identify embryos with genes for specific diseases. By doing this testing, parents could reduce risks of passing on an inherited condition. We recommend this testing for the couples who have a family history of genetic diseases who worry about passing it on their offspring such as thalassaemia, Marfan syndrome, Huntington disease, cystic fibrosis, sickle cells disease, Haemophilia. PGT-M requires personalised test.

As PGT-M is a test tailor made to look for specific genetic disorders running in a family, and it requires pre-work out. PGT-M can also be run in conjunction with HLA typing.

PGT using the latest High Resolution Next Generation Sequencing technology

The High Resolution-Next Generation Sequencing (Hr-NGS) is the most advanced pre-implantation screening to date, with each sample given an additional molecular code to eliminate the possibility of errors. The DNA collected from the embryo is tested directly, without the use of lights or markers as with earlier PGT screenings.

The Hr-NGS tests all 24 chromosomes with a single cell from the embryo, and contains information that indicates not just the condition of the embryo but the potential health risks of the child decades down the line. Hr-NGS is expected to change the world of genetics in time to come, offering uncannily accurate predictions of a person’s health conditions even before birth, fully embodying its name as a screening of the ‘next generation’.