PGT-SR Testing in Thailand: A Guide for International Patients with Chromosomal Rearrangements

PGT-SR is a type of preimplantation genetic testing performed on embryos created through IVF. It is designed for people who carry a structural chromosomal rearrangement, such as a translocation or inversion, that raises the chance of an embryo having an unbalanced chromosome makeup. Testing aims to identify embryos with a balanced or normal result for the chromosomes involved. It cannot guarantee a pregnancy, a live birth, or a healthy child, and it is not necessary or suitable for everyone. In Thailand, availability, laboratory methods, and what is reported back can differ between clinics, so the practical details are best confirmed directly with the provider you are considering.

At a glance

• What it is: PGT-SR looks at chromosome structure in IVF embryos, focusing on rearrangements known to be present in a parent.
• Who it may be relevant for: People with a confirmed balanced translocation, Robertsonian translocation, inversion, or a similar structural rearrangement.
• How it differs: PGT-A screens for extra or missing whole chromosomes; PGT-M looks for a specific inherited condition; PGT-SR targets structural rearrangements.
• What it cannot do: It cannot guarantee an embryo will implant, that a pregnancy will continue, or that a child will be unaffected by other genetic factors.
• Key planning step: Confirm the clinic’s laboratory method, what the report will show, and how results are explained to you.

What PGT-SR is and how it differs from PGT-A and PGT-M

Preimplantation genetic testing (PGT) is an umbrella term for several types of embryo testing done during IVF. The three most commonly discussed are PGT-A, PGT-M, and PGT-SR.

PGT-A (aneuploidy screening) looks at whether an embryo has the expected number of whole chromosomes. It is often discussed in the context of age-related chromosome risk, but it does not examine the fine structure of chromosomes in the way PGT-SR does.

PGT-M (monogenic) is used when a specific single-gene condition runs in a family. It looks for a known DNA change rather than a chromosome rearrangement.

PGT-SR (structural rearrangement) is used when a parent carries a rearrangement in which chromosome material has been rearranged rather than simply gained or lost. The goal is to identify embryos whose chromosomes are balanced or normal for the regions involved, so that an unbalanced arrangement is less likely to be transferred.

These tests are not interchangeable. Which one, if any, is relevant depends on the specific finding in the parent or parents, and that is a clinical judgement made with a genetic professional.

Who might consider PGT-SR

PGT-SR is generally discussed when a structural chromosomal rearrangement has already been identified, usually through karyotyping or another genetic test. Examples include:

• A balanced translocation, where chromosome material has swapped between chromosomes without obvious loss or gain.
• A Robertsonian translocation, a specific type of rearrangement involving certain chromosomes.
• An inversion, where a segment of a chromosome is reversed.
• A history of recurrent pregnancy loss or a previous pregnancy with a chromosome imbalance, where a rearrangement has been found in a parent.

Carrying a balanced rearrangement often has no effect on a person’s own health, but it can affect the balance of chromosomes passed to an embryo. PGT-SR is one way some people try to reduce that risk. It is not the only option, and it is not automatically recommended for everyone with a rearrangement. Some people conceive without assistance, some use IVF without PGT-SR, and some use donor gametes. These are personal decisions that should be discussed with a genetic counsellor and a fertility specialist.

How the process usually works

The exact steps vary by clinic, but the general sequence for an international patient often looks like this:

1. Genetic review before treatment. Your rearrangement is confirmed and characterised, often with a karyotype and sometimes additional testing. The clinic needs to know exactly which chromosomes are involved.
2. IVF cycle. Eggs are collected and fertilised, and embryos are grown in the laboratory.
3. Embryo biopsy. At a suitable stage, a small number of cells are removed from each embryo for testing. The embryo itself is not altered.
4. Laboratory analysis. The biopsy sample is analysed using a method chosen by the laboratory. Different methods have different strengths and limits, and not every laboratory offers every method.
5. Results and discussion. Results are reported for each tested embryo. A genetic counsellor or clinician should explain what the result does and does not mean.
6. Transfer decision. You and your clinician decide which embryo, if any, to transfer. PGT-SR results are one factor among several.

Because the test is built around your specific rearrangement, the laboratory usually needs your genetic reports in advance. Sending them early can help the clinic confirm whether it can offer the test and how long the setup may take.

What PGT-SR can and cannot tell you

PGT-SR can provide information about the chromosomes involved in the known rearrangement. In many cases it helps distinguish embryos that are balanced or normal for those chromosomes from those that are unbalanced.

It cannot:

• Guarantee that an embryo will implant or that a pregnancy will result in a live birth.
• Rule out all genetic conditions. It focuses on the rearrangement in question, not on every possible chromosome or gene issue.
• Replace diagnostic testing during pregnancy if that is something you and your clinician decide to consider.
• Predict how a child will develop or what their health will be like in later life.

There are also technical limits. Some rearrangements are more complex than others, and some results may be less clear-cut. A result may be reported as balanced, unbalanced, or sometimes inconclusive. How these categories are defined and explained can differ between laboratories.

PGT-SR in Thailand: what international patients should confirm

Thailand has a number of fertility clinics that see international patients, and some offer PGT. Availability of PGT-SR specifically, and the laboratory arrangements behind it, can vary. Rather than assuming a particular service is available, it is reasonable to ask direct questions before committing to treatment.

Useful questions include:

• Does the clinic offer PGT-SR for my specific rearrangement, and which laboratory performs the analysis?
• What testing method is used, and what are its known limitations for my case?
• What information and documents do you need from me before you can confirm whether you can offer the test?
• How will results be reported, and who will explain them to me?
• What are the possible outcomes for each embryo, and what happens if a result is inconclusive?
• What are the costs involved, including any separate laboratory fees, and what is not included?
• How long does the whole process take, including any setup time before my IVF cycle?
• What support is available if I am travelling from abroad, and how are follow-up appointments handled?

It is also worth asking whether genetic counselling is available, either at the clinic or through a separate service, because understanding your own rearrangement is the foundation for deciding whether PGT-SR is right for you.

Comparing PGT options at a glance

Test	Main focus	Typical situation
PGT-A	Number of whole chromosomes	Often discussed in relation to age-related chromosome risk
PGT-M	A specific inherited single-gene condition	When a known condition runs in the family
PGT-SR	Structural rearrangements such as translocations or inversions	When a parent carries a confirmed structural rearrangement

This table is a general orientation only. It does not indicate which test is appropriate for any individual, and more than one type of testing may sometimes be discussed.

Alternatives and limitations to keep in mind

PGT-SR is one path among several. Alternatives that people sometimes consider include:

• IVF without PGT-SR, with or without other forms of embryo assessment.
• Using donor eggs or donor sperm, which changes the genetic contribution to the embryo.
• Conceiving without assisted reproduction, with or without prenatal testing if a pregnancy occurs.
• Choosing not to pursue treatment at all, or to pause and gather more information first.

Each option has its own trade-offs. PGT-SR involves IVF, which has its own physical and emotional demands, and it adds laboratory costs. It may reduce the chance of transferring an embryo with an unbalanced rearrangement, but it does not remove all uncertainty, and it may leave fewer embryos available for transfer. For some people, the number of embryos suitable for transfer after testing is small, and that is an important part of the decision.

A short next-step checklist

• Gather your genetic reports, including the karyotype or other test that identified your rearrangement.
• Ask your current clinician or a genetic counsellor to explain your rearrangement in plain language.
• Shortlist clinics in Thailand that offer PGT-SR and ask the questions above.
• Confirm costs, timelines, and what is included before you travel.
• Check what follow-up and genetic counselling will be available to you.
• Take time to consider whether PGT-SR fits your goals, and whether you would proceed with IVF if testing were not available.

For more background, see our PGT in Thailand overview and our guides section. If you have a specific question, our FAQ may help.

Frequently asked questions

Is PGT-SR the same as PGT-A?

No. PGT-A looks at the number of whole chromosomes, while PGT-SR focuses on structural rearrangements such as translocations or inversions. They are different tests with different purposes, and one does not replace the other.

Does PGT-SR guarantee a healthy baby?

No. PGT-SR can provide information about the chromosomes involved in a known rearrangement, but it cannot guarantee a pregnancy, a live birth, or a child without any health or genetic issues. It is one part of a broader clinical picture.

Can I arrange PGT-SR in Thailand as an international patient?

Some clinics in Thailand offer PGT services and see international patients, but availability of PGT-SR specifically can vary. You would need to confirm with the clinic whether they can test for your particular rearrangement, what laboratory they use, and what information they need from you in advance.

What should I ask a clinic before choosing PGT-SR?

Ask whether they offer PGT-SR for your rearrangement, which laboratory performs the analysis, what method is used, how results are reported, what the costs include, how long the process takes, and what genetic counselling is available. It also helps to ask what happens if a result is inconclusive.

Are there alternatives to PGT-SR?

Yes. Alternatives can include IVF without PGT-SR, using donor eggs or sperm, conceiving without assisted reproduction, or deciding not to pursue treatment. Each option has different implications, and a genetic counsellor or fertility specialist can help you weigh them.

Continue your research

• PGT in Thailand overview
• PGT and IVF guides
• Frequently asked questions

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.