PGT and IVF Success: What Does the Research Show?
Preimplantation genetic testing (PGT) is an add-on to IVF that screens embryos for genetic or chromosomal issues before transfer. While PGT can help select embryos with a higher chance of implantation, it does not guarantee pregnancy or live birth. Success rates depend on many factors, including maternal age, embryo quality, and the specific genetic condition being tested.
In Thailand, many fertility centers offer PGT-A (aneuploidy screening), PGT-M (monogenic disorders), and PGT-SR (structural rearrangements). However, published success rates vary widely, and not all clinics report outcomes consistently. This guide explains what PGT can and cannot do, and how to evaluate success rates when comparing clinics.
At a Glance: Key Points About PGT Success
- PGT-A screens for chromosomal abnormalities; it may reduce miscarriage risk but does not improve overall live birth rates for all patients.
- PGT-M is used to avoid specific inherited diseases; success depends on the accuracy of the genetic test and embryo quality.
- PGT-SR helps identify embryos with balanced chromosomal rearrangements; live birth rates vary by rearrangement type.
- Success rates are influenced by maternal age, number of embryos, and laboratory quality.
- No test can guarantee a healthy baby; PGT is a tool, not a promise.
What Is PGT and How Does It Work?
PGT involves taking a few cells from a day-5 or day-6 embryo (blastocyst) and analyzing them for genetic or chromosomal issues. The embryo is then frozen while the results are pending. Only embryos that appear normal are considered for transfer.
There are three main types:
- PGT-A (aneuploidy screening): checks for extra or missing chromosomes, which are common causes of implantation failure and miscarriage.
- PGT-M (monogenic disorders): tests for specific single-gene diseases, such as cystic fibrosis or thalassemia.
- PGT-SR (structural rearrangements): detects unbalanced chromosomal rearrangements, which can lead to miscarriage or birth defects.
Each type has its own limitations. For example, PGT-A cannot detect all chromosomal abnormalities, and PGT-M requires a customized test for each family’s mutation.
Success Rates: What Do They Mean?
Success rates are usually reported as live birth per embryo transfer or per cycle. However, these numbers can be misleading if you don’t know the denominator. For instance, a clinic may report high success rates per transfer but exclude cycles where no embryos were available for transfer.
When comparing clinics, ask for:
- Live birth rate per started cycle (includes all cycles, even those that don’t reach transfer)
- Live birth rate per embryo transfer (only cycles with a transfer)
- Miscarriage rate after PGT
- Number of cycles performed (larger numbers are more reliable)
Also consider the patient population. A clinic that treats younger patients will naturally have higher success rates. Ask for age-stratified data if possible.
Factors That Influence PGT Success in Thailand
Several factors affect your chances of success with PGT in Thailand:
- Maternal age: Younger women typically produce more chromosomally normal embryos.
- Number of embryos: The more embryos you have, the higher the chance of finding a normal one.
- Embryo quality: Even a genetically normal embryo may not implant if it is of poor quality.
- Laboratory standards: The accuracy of PGT depends on the lab’s experience and technology.
- Genetic condition: For PGT-M, the test must be highly accurate for your specific mutation.
These factors are not unique to Thailand, but they are important to discuss with your clinic.
How to Interpret Clinic-Reported Success Rates
When you see a success rate, ask yourself:
- Is this rate for PGT-A, PGT-M, or PGT-SR? They are not the same.
- What is the patient age range?
- Is this per cycle, per transfer, or per embryo?
- How many cycles were included?
Be cautious of rates that seem too high. No clinic can guarantee a live birth. Also, remember that PGT does not improve the quality of your eggs or embryos; it only helps select among what you have.
Questions to Ask Your Clinic
Before choosing a clinic for PGT in Thailand, consider asking:
- What is your live birth rate per cycle for patients in my age group?
- How many PGT cycles do you perform per year?
- What is your embryo biopsy success rate (i.e., how often do embryos survive the biopsy)?
- Do you use next-generation sequencing (NGS) for PGT-A?
- How do you handle embryos with no result or mosaic results?
- What are the additional costs for PGT, and are there any hidden fees?
These questions can help you compare clinics on a like-for-like basis.
Next Steps: Making an Informed Decision
If you are considering PGT in Thailand, follow these steps:
- Research clinics that offer PGT and have experience with your specific situation.
- Request a consultation to discuss your medical history and whether PGT is appropriate.
- Ask for success rates in writing, and clarify how they are calculated.
- Consider genetic counseling to understand the limitations and risks of PGT.
- Review the costs and logistics, including travel and accommodation if you are coming from abroad.
Remember, PGT is not for everyone. Your doctor can help you decide if it is likely to benefit you.
Conclusion
PGT can be a valuable tool in IVF, but success rates in Thailand vary by clinic and patient. By understanding what PGT can and cannot do, and by asking the right questions, you can make a more informed decision. Always consult with a qualified fertility specialist to discuss your individual chances.
Frequently asked questions
What is the success rate of PGT-A in Thailand?
Success rates for PGT-A vary by clinic and patient age. There is no single national rate. Ask clinics for their live birth rate per cycle for your age group, and note that PGT-A does not guarantee a live birth.
Does PGT-M improve IVF success rates?
PGT-M is designed to avoid specific genetic diseases, not necessarily to improve overall success rates. Its success depends on the accuracy of the test and the number of healthy embryos available.
Are PGT success rates higher in Bangkok clinics?
Some Bangkok clinics may report higher success rates, but this can be due to patient selection or reporting methods. Compare clinics using consistent criteria, such as live birth per cycle for your age group.
Can PGT guarantee a healthy baby?
No. PGT reduces the risk of transferring embryos with certain genetic or chromosomal issues, but it cannot eliminate all risks. Miscarriage and birth defects can still occur.
Continue your research
Medical information notice: This article is educational and does not replace individual assessment, diagnosis, genetic counselling or treatment advice from a licensed clinician. Provider services, availability, fees and policies should be verified directly before booking.