PGT

Preimplantation Genetic Testing (PGT) is an advanced reproductive technology designed to enhance the success of In Vitro Fertilization (IVF) by screening embryos for genetic abnormalities before they are implanted in the uterus. By identifying healthy embryos that are free from specific genetic defects or chromosomal imbalances, PGT significantly improves the chances of a successful pregnancy and reduces the likelihood of passing on inherited genetic conditions to the next generation. This process offers couples not only a higher probability of achieving a healthy pregnancy but also peace of mind about the genetic health of their future child.

PGT is a breakthrough in fertility care because it addresses one of the primary reasons for IVF failures—genetic abnormalities in embryos. Even with a successful fertilization process, many embryos may carry chromosomal or genetic defects that lead to miscarriage, failed implantation, or developmental problems later in pregnancy. Through PGT, fertility specialists can carefully select embryos that are most likely to result in a healthy, viable pregnancy, giving couples an enhanced chance of achieving their goal of becoming parents.

To address different concerns. The three main types of PGT are:

• PGT-A (Preimplantation Genetic Testing for Aneuploidy):
  PGT-A is designed to detect aneuploidies, or abnormalities in the number of chromosomes. A healthy embryo typically contains 23 pairs of chromosomes. However, an embryo with too few or too many chromosomes can lead to conditions such as Down syndrome (trisomy 21), Turner syndrome, or Edwards syndrome (trisomy 18). By identifying embryos with the correct number of chromosomes, PGT-A reduces the risk of chromosomal disorders and increases the chances of successful implantation and a healthy pregnancy.
• PGT-M (Preimplantation Genetic Testing for Monogenic Disorders):
  PGT-M focuses on screening embryos for specific inherited single-gene disorders, such as cystic fibrosis, Tay-Sachs disease, Huntington’s disease, and sickle cell anemia. Couples who are carriers of a genetic mutation, or those with a family history of certain genetic diseases, can benefit greatly from PGT-M, as it ensures that only embryos without these inherited conditions are considered for transfer.
• PGT-SR (Preimplantation Genetic Testing for Structural Rearrangements):
  PGT-SR is used to detect chromosomal structural rearrangements, such as translocations (when parts of chromosomes exchange places) and inversions (where sections of a chromosome are reversed). These rearrangements can lead to miscarriage, failed implantation, or developmental issues. PGT-SR ensures that embryos with normal chromosome structures are selected for transfer, improving the chances of a healthy pregnancy.

PGT is a valuable option for many couples undergoing fertility treatments, particularly those who are at higher risk for genetic abnormalities. Some situations where PGT may be highly beneficial include:

1. Advanced Maternal Age:
   Women over the age of 35 are more likely to produce eggs with chromosomal abnormalities. PGT can help identify embryos with normal chromosomal structures, reducing the risk of miscarriage and improving the success rate of IVF.
2. Recurrent Pregnancy Loss:
   Couples who have experienced multiple miscarriages may benefit from PGT, as chromosomal abnormalities are a common cause of miscarriage. By selecting healthy embryos, the likelihood of a successful pregnancy increases.
3. Previous IVF Failures:
   For couples who have gone through IVF cycles without success, PGT may offer a solution. Screening embryos for genetic abnormalities before transfer can help increase the chances of a successful outcome.
4. Known Genetic Disorders in the Family:
   If either partner carries a known genetic mutation or if there is a history of genetic disorders in the family, PGT-M can help ensure that embryos are free from those specific genetic conditions.
5. Balanced Translocation Carriers:
   Couples where one or both partners have a balanced chromosomal translocation (a rearrangement of genetic material) may produce embryos with unbalanced translocations, leading to miscarriage or failed IVF attempts. PGT-SR can identify embryos with balanced chromosomal structures for transfer.

The use of PGT in IVF offers several significant advantages, including:

• Improved Pregnancy Success Rates:
  By selecting only genetically healthy embryos, PGT enhances the chances of successful implantation, reducing the need for multiple IVF cycles and increasing the overall success rates of achieving a healthy pregnancy.
• Reduced Risk of Genetic Disorders:
  PGT helps minimize the risk of passing on inherited genetic disorders, giving couples with a family history of certain conditions the peace of mind that they can have a healthy baby free from those disorders.
• Decreased Risk of Miscarriage:
  Since chromosomal abnormalities are a common cause of miscarriage, selecting chromosomally normal embryos through PGT reduces the likelihood of pregnancy loss.
• More Informed Decisions:
  PGT provides couples with detailed information about their embryos, allowing them to make informed decisions about their fertility treatment and family planning.
• Potential for Single Embryo Transfer (SET):
  With the ability to select the healthiest embryos, PGT increases the chances of success with single embryo transfer, reducing the risks associated with multiple pregnancies, such as premature birth or low birth weight.

PGT is an integrated part of the IVF process, involving several key stages:

1. IVF and Embryo Development:
   The process begins with IVF, where eggs are retrieved from the ovaries and fertilized with sperm in the lab. The resulting embryos are cultured for 5–6 days, reaching the blastocyst stage.
2. Embryo Biopsy:
   Once the embryos reach the blastocyst stage, a few cells from each embryo are carefully biopsied. This process is non-invasive to the embryo itself and does not harm its development.
3. Genetic Testing in the Laboratory:
   The biopsied cells are then sent to a specialized genetic laboratory, where they are tested for chromosomal abnormalities or specific genetic mutations based on the type of PGT being performed (PGT-A, PGT-M, or PGT-SR).
4. Selection of Healthy Embryos:
   After the genetic testing is complete, the results are reviewed, and only the healthiest embryos, free from genetic or chromosomal defects, are selected for transfer.
5. Embryo Transfer:
   Once a healthy embryo is selected, it is transferred to the uterus during the IVF process. If successful, the embryo will implant and develop into a healthy pregnancy.
6. Cryopreservation of Remaining Embryos:
   Any additional healthy embryos that are not transferred during the current cycle can be cryopreserved (frozen) for future use.

Deciding to undergo PGT is a deeply personal decision that depends on various factors, including your medical history, genetic background, and fertility goals. Consulting with your fertility specialist will help you determine whether PGT is the right path for you. By identifying and selecting the healthiest embryos for transfer, PGT can not only increase the chances of a successful pregnancy but also provide reassurance that your future child is less likely to be affected by genetic disorders.