Mosaic Embryo Results in Thailand: Questions to Ask Before Deciding Next Steps

If you have received a mosaic PGT result from a clinic in Thailand, you are likely facing a decision that feels urgent but is rarely straightforward. A mosaic result means the laboratory detected a mix of cells with different chromosomal patterns in the same embryo biopsy. It is a laboratory category, not a diagnosis of a specific health outcome. The meaning depends on the type of PGT performed, how the result was reported, and what your clinic can explain about its own thresholds and follow-up options. This guide helps you prepare questions so you can have a more informed conversation with your treating team.

At a glance

• A mosaic result is a laboratory finding, not a guarantee of any particular pregnancy or child health outcome.
• Different clinics may use different reporting categories and thresholds for calling a result mosaic.
• PGT-A, PGT-M, and PGT-SR are different tests with different purposes; a mosaic finding is most commonly discussed in the context of PGT-A.
• Your next steps depend on your full clinical picture, the specific embryo, and your clinic’s protocols.
• You are allowed to ask for clarification, a second review, or more time before deciding.

What “mosaic” means in a PGT report

Preimplantation genetic testing (PGT) involves testing a small sample of cells from an embryo. PGT-A looks at chromosome number, PGT-M looks for a specific inherited condition, and PGT-SR looks at structural chromosome rearrangements. A mosaic result usually comes from PGT-A and means the laboratory saw evidence of more than one chromosomal pattern in the sampled cells.

Mosaicism can be full or partial, and it can involve different chromosomes. Some laboratories report a percentage or a range, while others use descriptive categories such as low-level or high-level. These categories are not standardized across all laboratories, and the same raw data might be described differently in another setting. That is why the report itself is only one part of the picture.

It is also important to know that a biopsy samples only a few cells from the outer layer of the embryo, while the inner cell mass — which can become the fetus — is not directly tested. This means a PGT result is an estimate, not a complete map of the embryo.

Why the same result can be explained differently

Clinics and laboratories vary in several ways that affect how a mosaic result is communicated:

• Reporting thresholds: The percentage of abnormal cells that triggers a “mosaic” label can differ between laboratories.
• Technology and analysis: Different platforms and software settings can influence what is detected and how it is classified.
• Counseling approach: Some teams present mosaic results with a range of possible interpretations; others may frame them more narrowly.
• Local practice norms: Professional guidelines and clinic policies in Thailand may differ from those in your home country.

Because of these differences, a mosaic result from one clinic may not be directly comparable to a mosaic result from another. If you are considering a second opinion, ask whether the original laboratory data can be reviewed rather than repeating the test on a new biopsy.

Questions to ask your clinic about the report

Use these questions as a starting point. You may want to write them down and take notes during your appointment.

1. Which type of PGT was performed on this embryo, and what was it looking for?
2. How does your laboratory define and report mosaicism? Is there a percentage or a category in my report?
3. Which chromosome or chromosomes were involved, and does that affect how you interpret the result?
4. Was the result reviewed by a geneticist or a second analyst? Can I have a copy of the full laboratory report?
5. How many cells were analyzed, and what is the margin of uncertainty in this result?
6. Does this result change the recommended next step for this specific embryo compared with other embryos in my cohort?
7. What would you tell a patient in my situation if she asked for your personal clinical view, separate from the laboratory category?

Questions about counseling and decision-making

Counseling should help you understand the range of possibilities, not push you toward a single choice. Consider asking:

• Who will explain this result to me — a doctor, a genetic counselor, or both?
• Can we schedule a dedicated counseling session rather than discussing it briefly during a monitoring visit?
• What are the general options for an embryo with a mosaic result, and what does each option involve in practical terms?
• What uncertainties remain even after counseling?
• Can I take time to decide, or is there a clinical reason for urgency?
• If I choose to transfer this embryo, what additional monitoring or testing would you recommend during pregnancy?
• If I choose not to transfer, what are the alternatives for this embryo, and what are the rules in Thailand?

You do not have to decide during the same appointment. It is reasonable to ask for a follow-up conversation or a written summary of what was discussed.

What to clarify about transfer, storage, and legal categories

Policies about embryo transfer, storage, donation, and disposal are clinic-specific and may also be shaped by Thai law and professional regulations. Because these details can change and vary between providers, confirm them directly with your clinic and, where relevant, with the appropriate authority. Ask:

• What is your clinic’s policy on transferring embryos with a mosaic result?
• Are there any additional consent forms or counseling requirements before a transfer of a mosaic embryo?
• How long can this embryo be stored, and what are the costs and renewal timelines?
• What are the options if we decide not to use this embryo — donation for research, donation to another patient, or disposal — and what does Thai law allow?
• Can you provide this information in writing so I can review it with my partner or family?

Preparing for a second opinion

If you want another perspective, you can ask your current clinic to share the laboratory report and relevant clinical notes with a second provider or genetic counselor. A second opinion does not necessarily mean repeating the IVF cycle or the biopsy. In some cases, a review of the existing data is enough to clarify the interpretation.

When seeking a second opinion, be clear about what you want: a review of the raw data, a counseling session, or a discussion of transfer options. Ask about any fees for record review or consultation, and confirm whether the second provider can communicate with your current clinic.

Practical next-step checklist

1. Request a copy of the full PGT laboratory report for the embryo in question.
2. Write down your top three questions before your next appointment.
3. Ask for a dedicated counseling session with someone qualified to explain mosaic results.
4. Clarify your clinic’s reporting thresholds and what the mosaic category means in their laboratory.
5. Ask about the range of options without being pressured to choose immediately.
6. Confirm storage, consent, and legal categories in writing.
7. Consider whether a second opinion or record review would help you feel more informed.
8. Take notes or bring a trusted person to the appointment if that helps you remember details.

Emotional and practical considerations

Receiving a mosaic result can be stressful, and it is normal to feel uncertain. You may find it helpful to talk with a counselor, a patient support group, or others who have faced similar decisions. Be cautious about online forums that present definitive claims about mosaic embryos; individual experiences vary, and no single story predicts your outcome.

If you are an international patient, also consider language barriers, time zone differences for follow-up calls, and the practicalities of staying in Thailand for additional appointments. Ask whether interpretation services are available and whether you can receive documents in your preferred language.

Where to learn more

For general background on PGT in Thailand, see our PGT in Thailand page. You can also browse our guides for related topics and check the FAQ for common questions about testing and coordination.

Frequently asked questions

Does a mosaic PGT result mean the embryo cannot be used?

Not necessarily. A mosaic result is a laboratory category, and clinics vary in how they counsel patients about it. Some embryos with mosaic results have been transferred, but outcomes depend on many factors. Your clinic can explain its own policy and the uncertainties involved. This information is not a recommendation to transfer or not transfer.

Can I get a second opinion on a mosaic result from a Thai clinic?

Yes, you can ask your clinic to share the laboratory report and relevant records with another provider or genetic counselor. A second opinion may involve reviewing the existing data rather than repeating the biopsy. Ask about any fees and whether the second provider can communicate with your current clinic.

Is mosaicism reported the same way in every laboratory?

No. Laboratories may use different thresholds, technologies, and reporting categories. A mosaic result from one laboratory may not be directly comparable to a mosaic result from another. Ask your clinic how their laboratory defines and reports mosaicism.

What should I ask about the legal and storage aspects of a mosaic embryo in Thailand?

Policies on transfer, storage, donation, and disposal can vary by clinic and may be affected by Thai law. Ask your clinic for written information about their policies and confirm any legal questions with the appropriate authority. This article does not provide legal advice.

Where can I find more general information about PGT in Thailand?

You can start with our PGT in Thailand page, browse our guides, and check the FAQ for related topics. These resources provide general education and are not a substitute for personalized medical advice.

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.