The path to parenthood can be filled with both excitement and uncertainty, especially for parents undergoing fertility treatments. Among the many advancements in reproductive health, Pre-Implantation Genetic Testing (PGT) has emerged as a powerful tool that empowers couples with vital information about their embryos. PGT, now makes it possible to identify genetic abnormalities before the implantation. This increases the likelihood of a successful pregnancy and the birth of a healthy baby.
This blog explores what PGT is and why it is important in supporting parents making
informed and confident decisions.
What is Pre-Implantation Genetic Testing?
Pre-Implantation Genetic Testing (PGT), refers to specialized procedure used in conjunction
with In Vitro Fertilization (IVF), to analyze the genetic material of embryos before they are
transferred to the uterus. After retrieval and fertilization, embryos are cultured for several
days prior to proceeding with the next stage of the process.
Few of the cells are biopsied from each embryo and sent for genetic analysis without
causing harm to the embryo.
PGT is categorized into three main types:
- PGT-A (Aneuploidy Screening): It screens for an abnormal number of chromosomes, which can lead to conditions such as Down’s syndrome or result in implantation failures.
- PGT-M (Monogenic Disorder Testing): It identifies specific inherited genetic disorders, including conditions like cystic fibrosis and Tay-Sachs disease.
- PGT-SR (Structural Rearrangement Testing): It screens for structural changes in chromosomes that could lead to miscarriage or congenital abnormalities.
Why is PGT Important in IVF?
For couples who invest emotionally and financially in IVF, it is quite natural to want to maximize the chances of success. PGT plays a vital role here.
Chromosomal abnormalities in embryos are a major cause of IVF failure, often preventing implantation or leading to miscarriage. By using PGT, specialists can identify and select embryos with the best potential for a successful pregnancy, thereby improving implantation rates.
PGT also provides reassurance to prospective parents with a known genetic condition or a
family history of inherited disorders. By minimizing the uncertainty surrounding genetic risks,
it ensures that only normal embryos are selected for transfer.
Key Benefits of PGT for Parents and Babies
PGT offers several advantages for individuals and couples navigating infertility:
1. Higher Success Rates with IVF
The success rate of IVF is significantly improved using PGT by identifying chromosomally normal embryo. Many fertility clinics report higher implantation and live birth rates among patients who undergo PGT.
2. Reduced Risk of Genetic Disorders
PGT-M reduces the likelihood of passing on serious genetic disorders, particularly for
parents with single-gene conditions. The procedure ensures only unaffected embryos
are selected for transfer.
3. Minimized Risk of Miscarriage
PGT-A help reduce the number of miscarriages caused by chromosomal abnormalities. Through this procedure, embryos with the right number of chromosomes are chosen thereby leading to more viable pregnancies.
4. Opportunity for Single Embryo Transfer (SET)
Reducing the risk of multiple gestation, with associated complications by knowing
which embryo has the highest potential, allows for a single, healthy embryo to be
transferred.
5. Emotional and Financial Relief
PGT can save future emotional distress and medical expenses related to miscarriage
or genetic illness even though the procedure adds upfront costs to IVF. For many, the
long-term advantages outweigh the PGT cost.
Who Should Consider PGT?
PGT is not necessary for every IVF patient, but it can be valuable for:
- Women over 35: The risk of chromosomal abnormalities increases with maternal age.
- Couples with a history of pregnancy loss: PGT can help identify viable embryos.
- Individuals with known genetic disorders: PGT-M can ensure these conditions are not passed on.
- Patients with multiple failed IVF cycles: Screening may help uncover underlying chromosomal issues.
- Couples with a family history of genetic conditions: In some cases, such couples can be carriers.
Ethical Considerations and Limitations
While PGT offers clear benefits, it is also important to acknowledge its ethical dimensions and limitations.
Ethical Concerns
Some individuals raise concerns about the ethical implications of embryos selection.
However, it is important to differentiate between the use of PGT to prevent severe
medical conditions and using it for non-medical reasons, raises more complex ethical
questions.
Accuracy and Limitations
PGT can be highly accurate but it never guarantees a baby free of health issues as it
never tests for every possible condition. Moreover, not all embryos survive the biopsy
process, however standardised lab practises coupled with the skills of lab personnel
reduce the risks.
Cost and Accessibility
PGT are expensive procedures and are not usually covered by insurance. This makes it challenging for some couples especially the ones in countries or regions with limited fertility care options.
Latest Advances and Research in PGT
Next-Generation Sequencing (NGS)
NGS is a cutting-edge technology that allows for a more precise and comprehensive
analysis of embryo chromosomes. Unlike older techniques like FISH or CGH
microarray, it significantly helps in identifying chromosomal defects even in poor-
quality embryos. It also provides higher accuracy in identifying aneuploidy.
Non-Invasive Embryo Testing Research
Traditionally, PGT requires a biopsy from the embryo which raises ethical concerns.
However, ongoing research is exploring non-invasive methods by analyzing cell-free
DNA that embryos release into the surrounding culture media. This innovation could
minimize the potential risks to embryos and make the testing safer. Non-invasive
PGT may soon become a game-changer in fertility care.
Ongoing Studies from ACOG, NIH, and Major Fertility Centers
Prestigious institutions like the American College of Obstetricians and Gynecologists (ACOG), the National Institutes of Health (NIH), and top fertility centers are actively conducting long-term studies on PGT outcomes. They investigate into live birth rates, genetic accuracy, and ethical practices to endure further advancements in PGT.
Conclusion
Pre-Implantation Genetic Testing (PGT) offers hope to many couples, by improving IVF
success rates, providing protection against genetic diseases, and offering support during a
delicate journey. While PGT may not be right for everyone, it can be a valuable option for
those facing specific fertility or genetic challenges. This technique turns uncertainty into
clarity, giving families a better chance for a healthy beginning.
