India welcomed its first In Vitro Fertilization (IVF) child Kanupriya Agarwal in the year 1978. Since then, IVF treatment has given hope to millions of childless Indian couples. It is a treatment that aids in the conception of a child and a method to treat infertility or genetic abnormalities. Even though IVF is the most effective method of assisted reproductive technology, the chances of having children are still dependent on many factors. A single IVF cycle lasts about two to three weeks and involves several steps. In addition to that, the treatment requires multiple cycles, and is both time-consuming and expensive.
Even though IVF is a very effective procedure, there is a chance that it will fail due to chromosomal defects in the embryos, such as missing, extra or irregular portion of chromosomal DNA. According to various studies, IVF tests have a success rate of 20-35 per cent per cycle. At the same time, with each IVF subsequent cycle, the chances of conceiving decrease. Genetic tests can assist you in having a best chance of success.
Genetic tests examine your DNA, the chemical database that contains instructions for your body’s functioning, to see if there are any modifications or abnormalities in your genes that could lead to an illness or a disease. Preimplantation Genetic Testing-Aneuploidy (PGT-A) is one genetic test that can help reduce the number of IVF cycles and increase the pregnancy rate to 73%.
What is Preimplantation Genetic Testing-Aneuploidy (PGT-A)?
PGT-A is an advanced technique for detecting chromosomal defects in IVF embryos (IVF). The test examines embryos before transfer. It involves removing one or more cells from an embryo to test for numerical chromosomal abnormalities. This screening method facilitates the selective transfer of embryos that have a normal number of chromosomes. This test reduces the likelihood of a future child having certain chromosomal disorders, reduces the chances of miscarriage and assists in a healthy pregnancy.
Here are a few conditions that PGT-A can detect:
- Down Syndrome
- Edwards Syndrome
- Patau Syndrome
- Turner Syndrome
- Klinefelter Syndrome
- Other trisomies and monosomies that increase the risk of implantation failure and miscarriage
- Segmental Gain and Losses (>20Mb) in chromosomes which can lead to abnormalities in the embryo
Clinical experts use this method to select embryos that do not carry chromosomal abnormalities and have a higher chance of successful IVF implantation and pregnancy. Sonam and Kunal’s case can be a study in its success. During their first pregnancy which was a normal conception, their child was diagnosed with Turner’s syndrome, which was detected on PGT testing, but in their second pregnancy, the child turned out to be normal. For another couple, PGT testing revealed that out of 15 embryos only two were normal. Therefore, with the advanced technology of PGT testing in IVF, they were able to avoid multiple embryo transfer failures. In addition, they achieved a healthy and happy pregnancy in their first attempt of embryo transfer.
Why do experts recommend PGT-A?
- Reduces the number of IVF cycles required to achieve a successful pregnancy
- Increases success rate for single embryo transfer
- Reduces the likelihood of miscarriage due to Aneuploidies
- Increases reproductive success rates in women above 35 years
Who needs PGT-A testing?
- Patients at any age who have repeated implantation failure or recurrent pregnancy loss while undergoing IVF
- Women over 35 years old undergoing IVF
- Couples with recurrent miscarriages
- Positive history of chromosomal abnormalities in the family
- Diagnosed carriers of chromosomal aberrations
- If PGT-M is being planned
Most individuals are still unaware of the significance and relevance of PGT-A. It is therefore imperative to raise awareness regarding the importance of PGT-A during IVF and educate people about how this test can help have a healthy pregnancy.
PGT – M
Genes play a critical role in our bodies and in how they function. Every gene occupies a specific location on the chromosome and directs the production of proteins, which determine the structure and function of the body. It implies that your genes are responsible for all the characteristics we inherit. These instructions can sometimes shift, resulting in a variation or gene change. It can also have a negative impact on the person’s health and cause diseases in future generations. Genetic tests like PGT-M help in detecting such disorders. Genetic testing is conducted in families where a child is affected by a specific disorder. In IVF, PGT-M can be recommended to select embryos without diseases caused by genetic variations.
The following points describe the kind of people who should get tested:
- Couples with a child with specific genetic mutation
- Couples in whom carrier screening or exome sequencing has detected a common deleterious variation which can cause a serious disease in their offspring
PGT technology has brought happiness into many lives and is a new ray of hope ensuring healthy outcomes for patients undergoing IVF treatment and helping to identify genetic abnormalities.
Authors Dr Rashmi Yogish is from Khushi Fertility Clinic and IVF centre) and Dr Priya Kadam is from MedGenome Labs. Views are personal.