Can Embryos Be Retested After an Inconclusive PGT Result?

Understanding an Inconclusive PGT Result

When you receive a preimplantation genetic testing (PGT) report, most embryos are reported as either chromosomally normal (euploid) or abnormal (aneuploid). However, sometimes a result is inconclusive, meaning the laboratory could not determine the embryo’s chromosomal status with confidence. This can happen for several reasons, such as DNA amplification failure, contamination, or technical issues during the biopsy or testing process.

An inconclusive result does not necessarily mean the embryo is abnormal. It simply means the test did not provide a clear answer. For many patients, the next question is whether that embryo can be retested. The short answer is yes, in many cases, but there are important limitations and considerations to discuss with your clinic.

At a Glance: Key Points About Embryo Retesting

• Inconclusive results are not the same as abnormal results.
• Retesting is possible in some cases, but it depends on the embryo’s stage and the reason for the inconclusive result.
• Re-biopsy involves removing additional cells, which carries a small risk to the embryo.
• Not all embryos survive the thawing and re-biopsy process.
• Your clinic can explain the specific success rates and risks based on your situation.

Why Might a PGT Result Be Inconclusive?

Several factors can lead to an inconclusive PGT result:

• DNA amplification failure: The tiny amount of DNA from the biopsy may not have amplified properly during testing.
• Contamination: External DNA may have interfered with the sample.
• Technical issues: Problems with the testing platform or analysis can prevent a clear result.
• Low cell quality: The biopsied cells may have been damaged or degraded.

Understanding the reason for the inconclusive result is important because it affects whether retesting is likely to be successful. Your clinic should provide a detailed explanation of your specific report.

Can Embryos Be Retested? The Role of Re-biopsy

In many fertility clinics, embryos that receive an inconclusive PGT result can be retested. This typically involves thawing the embryo (if it was frozen), performing a new biopsy to remove additional cells, and sending those cells for genetic analysis again. However, this process is not always straightforward.

When Retesting May Be Possible

• If the embryo is at the blastocyst stage (day 5 or 6) and has enough cells to safely biopsy again.
• If the initial inconclusive result was due to a technical issue that can be corrected.
• If the embryo survives the thawing process and remains viable after re-biopsy.

When Retesting May Not Be Recommended

• If the embryo has very few cells or is of poor quality.
• If the risk of damage from another biopsy is considered too high.
• If the clinic’s laboratory does not offer re-biopsy services.

It is essential to have a detailed discussion with your fertility specialist about whether retesting is a viable option for your specific embryo.

Risks and Limitations of Re-biopsy

Re-biopsy is not without risks. The main concerns include:

• Embryo damage: Removing additional cells can harm the embryo, potentially reducing its ability to implant or develop.
• Thawing survival: Not all embryos survive the freeze-thaw process, especially if they have already been biopsied once.
• Inconclusive again: There is a chance that the retest will also be inconclusive, leaving you with the same uncertainty.

Your clinic should provide you with data on their re-biopsy success rates and the risks involved. Remember that these rates can vary between clinics and laboratories.

Alternatives to Retesting

If retesting is not recommended or you prefer not to take the risk, there are alternatives to consider:

• Transfer without testing: You may choose to transfer the embryo without knowing its chromosomal status. This is a personal decision that should be made with your doctor’s guidance.
• Use another embryo: If you have other embryos with clear results, you might prioritize transferring those first.
• Consider additional testing: In some cases, other types of genetic testing or screening may be available, but this depends on your specific situation.

Each option has its own benefits and risks, and the right choice depends on your medical history, preferences, and the advice of your healthcare team.

Questions to Ask Your Clinic About Retesting

When discussing an inconclusive PGT result with your clinic, consider asking the following questions:

• Why was the result inconclusive for this embryo?
• Is re-biopsy possible for this embryo, and what are the success rates at your laboratory?
• What are the risks of re-biopsy for this specific embryo?
• How long does the retesting process take?
• What are the costs associated with retesting?
• If retesting is not possible, what are my options?

These questions can help you make an informed decision about your next steps.

Next Steps: Making a Decision

After receiving an inconclusive PGT result, take time to process the information and consult with your fertility team. Here is a simple checklist to guide you:

1. Request a detailed explanation of the inconclusive result from your clinic.
2. Ask about the possibility of re-biopsy and the associated risks and benefits.
3. Discuss alternative options, such as transferring without testing or using another embryo.
4. Consider seeking a second opinion if you are unsure about the recommendations.
5. Make a decision that aligns with your values and medical advice.

Remember, an inconclusive result is not a definitive answer about the embryo’s health. With the right information and support, you can navigate this situation with confidence.

Frequently asked questions

What does an inconclusive PGT result mean?

An inconclusive PGT result means the laboratory could not determine whether the embryo has a normal or abnormal number of chromosomes. This can happen due to technical issues, such as DNA amplification failure or contamination, and does not necessarily indicate that the embryo is abnormal.

Is it safe to re-biopsy an embryo for retesting?

Re-biopsy carries some risks, including potential damage to the embryo and the possibility that the embryo may not survive the thawing and biopsy process. Your clinic can provide specific information about the risks and success rates based on your embryo's quality and stage.

What are the alternatives if retesting is not possible?

If retesting is not recommended, you may consider transferring the embryo without testing, using another embryo with a clear result, or discussing other genetic testing options with your clinic. The best choice depends on your individual circumstances and 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.