Thailand PGT IVF Success Rates Explained: How to Read Clinic Claims

PGT IVF success rates from Thai clinics are usually reported as percentages, but those percentages can describe very different things. A figure may refer to embryos that reach a certain stage, to a pregnancy confirmed by scan, or to a live birth. It may apply to a narrow age group or to a mixed group of patients. Because of this, a single headline number rarely tells you what your own chance of a live birth will be. This guide explains how to read PGT success claims carefully, what PGT can and cannot do, and what to confirm directly with a clinic.

At a glance

• PGT is a laboratory step used during IVF to examine embryos for specific genetic or chromosomal features.
• PGT does not guarantee a pregnancy, a live birth, or a healthy child.
• Success rates depend heavily on age, egg and sperm factors, embryo development, and the clinic’s own definitions.
• Ask what the denominator is: per cycle started, per egg retrieval, per embryo transfer, or per embryo tested.
• Ask whether the rate refers to pregnancy, ongoing pregnancy, or live birth.
• Ask which patient groups are included and whether the data are internally audited.

What PGT actually is

Preimplantation genetic testing (PGT) is an umbrella term for laboratory tests performed on embryos created through IVF. A small number of cells are usually removed from an embryo at a specific stage of development, and those cells are tested. The main categories are:

• PGT-A (aneuploidy screening): looks at chromosome number, such as whether an embryo has an extra or missing chromosome.
• PGT-M (monogenic/single gene): looks for a specific inherited condition that runs in a family.
• PGT-SR (structural rearrangement): looks at chromosome structure, for example where a parent carries a balanced translocation.

PGT is not a treatment that improves an embryo. It is a way of selecting which embryos to transfer, based on the information the test provides. Some embryos may be classified as suitable for transfer, some as not suitable, and some results may be inconclusive or not reportable. A clinic can explain how it handles each of these outcomes.

Why PGT success rates are easy to misread

Success rate claims often differ because of what is being counted. Two clinics can both report a percentage, yet be measuring completely different events. Common variations include:

• Starting point: cycles started, egg retrievals performed, embryos created, embryos tested, or transfers completed.
• Outcome point: a positive pregnancy test, a visible pregnancy on ultrasound, an ongoing pregnancy, or a live birth.
• Patient mix: age bands, diagnosis, previous IVF history, and whether donor eggs were used.
• Embryo stage: whether the transfer was of a tested embryo, an untested embryo, or a mosaic embryo.
• Time period: which years are included and whether older data are mixed with recent data.

Without these details, a percentage is difficult to compare. A rate that sounds high may be based on a small, selected group. A rate that sounds lower may include more challenging cases.

How age affects PGT outcomes

Age is one of the strongest factors influencing IVF outcomes, including when PGT is used. As age increases, the number of eggs retrieved and the proportion of embryos with normal chromosome number tend to decline. This means that even with PGT, the chance of having a transferable embryo and a live birth generally decreases with age.

Because of this, a clinic’s overall success rate can be misleading if it does not show results by age group. Ask for age-specific data, and ask how many patients in each group had a transfer. A high rate in a younger group does not predict the same result for an older patient, and vice versa.

What PGT can and cannot tell you

PGT can provide information about specific chromosomal or genetic features in the cells that were tested. It cannot:

• Guarantee that an embryo will implant.
• Guarantee a live birth or a healthy child.
• Detect every possible genetic condition.
• Predict how a pregnancy will progress.
• Replace the need for prenatal testing if that is recommended.

Some results are uncertain. For example, a mosaic result means that the tested cells show a mix of normal and abnormal chromosome patterns. Clinics may differ in how they report and act on mosaic results. Ask how your clinic defines and manages these situations.

Questions to ask a clinic about its success data

Use these questions to move from a headline number to a clearer picture. You can ask them in writing and request a written reply.

1. What exactly does your published success rate measure: pregnancy, ongoing pregnancy, or live birth?
2. Is the rate calculated per cycle started, per egg retrieval, per transfer, or per embryo tested?
3. Can you show results by age group and by whether PGT was used?
4. How many patients are included in each group, and over what time period?
5. How do you handle cycles with no transfer, cancelled cycles, or inconclusive PGT results in your reporting?
6. Do you use donor eggs or donor sperm in the reported group, and are those results separated?
7. Who reviews your outcome data internally, and how often?
8. What are your laboratory’s policies for embryo biopsy, testing, and reporting?
9. What alternatives to PGT do you discuss, and how do you help patients decide?
10. What costs are involved in PGT, and what happens if testing is inconclusive or no embryo is suitable for transfer?

Reading clinic-reported data without overinterpreting it

Clinic-reported data can be useful, but it is not the same as independent verification. When you review a clinic’s figures, look for:

• Clear definitions of the numerator and denominator.
• Age-specific breakdowns rather than one overall number.
• Separation of PGT and non-PGT cycles.
• Information about transfer rates, not just pregnancy rates.
• Notes on exclusions, such as cancelled cycles or patients who did not proceed to transfer.

If a clinic cannot explain how its numbers are calculated, treat the figure as a general orientation rather than a personal prediction. You can also ask whether the clinic participates in any external quality assessment or data reporting, and what that involves.

PGT efficacy in Thailand: what to confirm locally

PGT services, laboratory arrangements, and reporting practices can vary between clinics and over time. Rules and requirements that affect international patients can also change. Because of this, confirm the following directly with the clinic and, where relevant, with the appropriate authority:

• Which PGT categories the clinic offers and which laboratory performs the testing.
• How results are reported, including inconclusive or mosaic results.
• What documents or identification you need before treatment.
• What the full cost includes, and what may be charged separately.
• Whether any legal or regulatory conditions apply to your situation.
• What follow-up and support are available if you return home after treatment.

A short next-step checklist

1. Write down your main question: are you trying to understand a clinic’s claim, or compare options?
2. Request written definitions of any success rate you are shown.
3. Ask for age-specific and PGT-specific data.
4. Ask how many patients were included and over what period.
5. Ask what happens when no embryo is available for transfer.
6. Ask about costs, documents, and any legal conditions in writing.
7. Take time to compare answers before making a decision.

For more context, see our guides on IVF success rates in Thailand, PGT in Thailand, and our patient guides. You can also review common questions in our FAQ.

Frequently asked questions

Do PGT success rates from Thai clinics tell me my own chance of having a baby?

Not directly. A clinic's reported rate is usually an average for a defined group of patients over a defined period. Your own chance depends on factors such as your age, egg and sperm quality, embryo development, and the specific PGT test used. Ask for age-specific data and a clear explanation of what the rate measures before you interpret it as a personal prediction.

What is the difference between a pregnancy rate and a live birth rate after PGT?

A pregnancy rate usually counts positive pregnancy tests or pregnancies seen on early ultrasound. A live birth rate counts babies born. These are different events, and a pregnancy may not continue to a live birth. When you compare clinics, check which outcome they are reporting and whether the definition is stated clearly.

Does PGT improve the chance of a live birth for everyone?

PGT is a selection tool, not a treatment that changes an embryo. Whether it is useful depends on the reason it is being considered, the number of embryos available, and the patient's circumstances. Some patients may be advised that PGT is unlikely to change their outcome, while others may be advised that it could provide useful information. Discuss the potential benefits and limitations with your treating clinician.

What should I ask if a clinic shows me a very high success rate?

Ask what the rate measures, how many patients are included, which age groups are represented, and whether PGT and non-PGT cycles are separated. Also ask how cancelled cycles, cycles with no transfer, and inconclusive results are counted. A high number without these details is difficult to interpret.

Can I get PGT results that are unclear?

Yes. Some results may be inconclusive, and some embryos may be reported as mosaic, meaning the tested cells show a mix of patterns. Clinics may differ in how they report and manage these results. Ask your clinic in advance how it handles unclear results and what options you would have.

Continue your research

• How to interpret IVF success rates
• PGT in Thailand overview
• PGT and IVF guides

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.