At a glance
PGT success rates are often quoted but rarely explained. Learn what these numbers mean, what they don't tell you, and how to ask better questions when comparing clinics in Thailand.
When you search for PGT success rates in Thailand, you will find many numbers. Some clinics publish pregnancy rates, others live birth rates, and some quote figures for very specific patient groups. These numbers can be useful, but they rarely mean what they appear to mean at first glance. A success rate is not a property of a clinic alone. It depends on who is treated, which test is used, how embryos are selected, and how the outcome is defined. This guide explains how to read PGT outcome claims carefully, what questions to ask, and why a single percentage should never be your only decision tool.
At a glance
- PGT success rates are not standardized across clinics or countries.
- Pregnancy rate and live birth rate are different measures.
- PGT-A, PGT-M, and PGT-SR answer different questions and have different expected outcomes.
- Patient age, embryo quality, and clinic laboratory practices strongly influence results.
- No test can guarantee a healthy pregnancy or a healthy child.
- Ask how a number was calculated before you compare it with another clinic.
What “success rate” actually means in PGT
In fertility care, success can be defined in several ways. A clinic might report the proportion of embryo transfers that resulted in a positive pregnancy test. Another might report clinical pregnancy, confirmed by ultrasound. Another might report live birth. These are not interchangeable. A positive pregnancy test is an early signal, not a guarantee that a pregnancy will continue. A live birth rate is a later and generally more meaningful outcome, but it is also influenced by factors that occur after the embryo transfer.
When you see a PGT success rate, the first question is: success at what point? Without that definition, the number is difficult to interpret. A high pregnancy rate with a lower live birth rate tells a different story than a high live birth rate. Neither is automatically better or worse without context.
Why PGT-A, PGT-M, and PGT-SR cannot share one success rate
Preimplantation genetic testing is an umbrella term. Each type of PGT has a different purpose, and that affects what a meaningful outcome looks like.
PGT-A
PGT-A screens embryos for extra or missing chromosomes. It is often used to help select embryos for transfer. The outcome depends heavily on how many embryos are available and how many are chromosomally normal. A clinic’s PGT-A results will vary with the average age of its patients and the number of embryos tested per cycle.
PGT-M
PGT-M looks for a specific inherited condition that runs in a family. Success here is often measured by whether an unaffected embryo is identified and available for transfer. The number of unaffected embryos can vary widely depending on the condition and the parents’ genetic status. A single success rate for PGT-M across all conditions would be misleading.
PGT-SR
PGT-SR is used when a parent has a known structural chromosome rearrangement, such as a translocation. The proportion of normal or balanced embryos can differ greatly from one rearrangement to another. Again, a general success rate cannot capture this variation.
Because these tests answer different questions, comparing a PGT-A rate with a PGT-M rate is not meaningful. Even within PGT-A, results depend on the patient population.
What influences PGT outcomes in Thailand and elsewhere
Many factors affect whether a PGT cycle leads to a live birth. Some are within a clinic’s control, and some are not.
- Patient age: The chance of having chromosomally normal embryos generally declines with age. This affects PGT-A outcomes more than any single laboratory technique.
- Number of embryos available: More embryos tested means more opportunities to find a suitable one for transfer. A cycle with few embryos has fewer chances.
- Embryo quality: Morphology and development speed still matter, even with genetic testing.
- Laboratory experience: Embryo biopsy, freezing, and genetic analysis are technical steps. Consistency and skill can influence results.
- Reason for testing: PGT-M and PGT-SR outcomes depend on the specific genetic condition or rearrangement.
- Definition of success: As noted above, pregnancy and live birth are different endpoints.
Because these factors vary so much, a clinic’s published rate may reflect its patient mix more than its quality of care. A clinic that treats many younger patients with a good prognosis may report higher rates than a clinic that accepts more complex cases.
How to read a PGT success rate claim
When you encounter a number, try to unpack it with these questions:
- Is this a pregnancy rate or a live birth rate?
- Does it refer to PGT-A, PGT-M, PGT-SR, or a mix?
- Is it per embryo transfer, per cycle started, or per patient?
- Does it include frozen embryo transfers or only fresh transfers?
- What is the age range and diagnosis of the patients included?
- Does it include cycles that were cancelled before transfer?
- Is the number based on the clinic’s own data, a registry, or a general estimate?
If a clinic cannot or will not answer these questions, treat the number with caution. A responsible clinic should be able to explain how its data are collected and what they represent.
Why comparing clinics by a single number is risky
International patients often look for a simple ranking. But a single success rate cannot tell you which clinic is right for you. Two clinics may report the same percentage while treating very different patients. One may specialize in older patients or complex genetic cases, while another may focus on routine IVF. The clinic with the higher number may simply have a less challenging patient population.
In addition, reporting practices differ. Some clinics publish data regularly; others do not. Some use internal audits; others participate in external registries. Without a common standard, direct comparison is unreliable.
This does not mean success rates are useless. They can be one part of your research. But they should be considered alongside the clinic’s experience with your specific situation, its laboratory practices, and how clearly it communicates uncertainty.
Questions to ask a clinic about PGT outcomes
When you contact a clinic in Thailand, consider asking these questions. You can also use them to compare written information from different providers.
- How do you define success for PGT cycles?
- Do you report live birth rates separately from pregnancy rates?
- Can you share outcome data for patients with my age range and diagnosis?
- How many PGT cycles do you perform in a typical year?
- What is your experience with my specific genetic condition or rearrangement, if applicable?
- What happens if no embryo is suitable for transfer after testing?
- Are there additional costs for PGT that are not included in the initial quote?
- How do you counsel patients about the limitations of PGT?
These questions help you move beyond a headline number and understand the clinic’s approach. They also give you a sense of how transparent the clinic is willing to be.
What PGT can and cannot tell you
PGT can provide information about the chromosomal or genetic status of an embryo. It can help some patients avoid transferring embryos with certain abnormalities. However, it cannot guarantee that a transferred embryo will implant, that a pregnancy will progress, or that a child will be free of all health conditions. PGT does not test for every possible genetic disorder, and it does not replace prenatal testing.
For some patients, PGT may not be necessary or may not improve their chances. For others, it may be a valuable tool. The decision depends on individual circumstances, and it should be made with a qualified healthcare provider who can explain the benefits and limitations.
Planning your next steps
If you are considering PGT in Thailand, start by clarifying your own priorities. Are you trying to reduce the risk of a specific inherited condition? Are you hoping to improve the chances of a successful pregnancy after multiple IVF attempts? Your reasons will shape which test is relevant and what outcomes matter most to you.
Next, gather information from several clinics. Ask for written explanations of their PGT process, their outcome reporting, and their costs. Compare not just numbers but also how clearly they answer your questions. A clinic that explains uncertainty honestly may be a better partner than one that promises more than it can deliver.
Finally, remember that success rates are only one piece of the puzzle. Your age, health, embryo quality, and the specific reason for testing all play a role. No clinic can guarantee a particular result, and any provider who does should be viewed with skepticism.
For more context on IVF outcomes in Thailand, see our guide to IVF success rates in Thailand. To understand the testing process itself, read about PGT in Thailand. You can also explore our patient guides and frequently asked questions for more planning support.
Frequently asked questions
What is a good PGT success rate in Thailand?
There is no single 'good' number because success rates depend on how they are defined and who is included. A rate that applies to one patient group may not apply to you. Instead of looking for a threshold, ask how the clinic measures success, whether it reports live birth rates, and whether it can share data for patients similar to you.
Can PGT guarantee a healthy baby?
No. PGT can provide information about certain chromosomal or genetic features of an embryo, but it cannot guarantee implantation, a continuing pregnancy, or a child free of all health conditions. It does not test for every possible disorder, and prenatal testing may still be recommended.
Why do PGT success rates vary so much between clinics?
Variation comes from differences in patient age, diagnosis, the type of PGT used, laboratory practices, and how outcomes are counted. A clinic with younger patients or simpler cases may report higher rates than one that treats more complex cases. Without standardized reporting, direct comparisons are unreliable.
Should I choose a clinic based only on its PGT success rate?
No. A single number cannot tell you whether a clinic is right for your situation. Consider the clinic's experience with your specific condition, its laboratory standards, how transparent it is about limitations, and how well it communicates. Success rates can be one factor among many.
What should I ask a clinic about its PGT data?
Ask whether the rate is for pregnancy or live birth, whether it is per transfer or per cycle, which PGT types are included, and what patient characteristics are represented. Also ask how many PGT cycles the clinic performs and what happens if no suitable embryo is found.
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.
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