How Many Embryos Should You Biopsy for PGT-A in Thailand?

When planning PGT-A (preimplantation genetic testing for aneuploidy) in Thailand, one of the first questions is: how many embryos should you biopsy? The answer depends on several personal factors, and there is no single number that fits everyone. This guide explains what influences the decision and helps you prepare for a conversation with your fertility clinic.

At a Glance: Key Factors in Embryo Count

• Age: Younger women typically produce more chromosomally normal embryos, so fewer may need testing.
• Embryo quality: Higher-quality embryos may have a better chance of being normal, but quality alone doesn’t guarantee it.
• Financial considerations: PGT-A adds to the cost of IVF, so the number biopsied affects your budget.
• Clinic policy: Some clinics have minimum or maximum numbers for biopsy; ask about their approach.

Understanding PGT-A and Embryo Biopsy

PGT-A screens embryos for chromosomal abnormalities before transfer. During IVF, embryos are cultured to the blastocyst stage (usually day 5 or 6), and a few cells are removed from the outer layer (trophectoderm) for testing. The biopsy is performed in a laboratory, and the embryos are frozen while awaiting results.

The number of embryos you biopsy is the number that reach the blastocyst stage and are suitable for biopsy. Not all fertilized eggs will develop to this stage, so the starting number of eggs and embryos is also relevant.

Factors That Influence How Many Embryos to Biopsy

Age and Ovarian Reserve

Age is a major factor in embryo aneuploidy rates. As women age, a higher percentage of embryos are expected to be chromosomally abnormal. Therefore, older women may need to biopsy more embryos to have a reasonable chance of finding at least one normal embryo. However, age is not the only factor; ovarian reserve (measured by AMH and antral follicle count) also affects how many eggs and embryos you produce.

Embryo Quality and Development

Embryos are graded based on their appearance and development. Higher-grade embryos are more likely to be normal, but even high-quality embryos can be abnormal. Some clinics recommend biopsying all embryos that reach the blastocyst stage, regardless of grade, to maximize information. Others may suggest biopsying only the best-quality embryos to reduce costs.

Financial Considerations

PGT-A is an additional cost on top of IVF. The cost per embryo can vary, and some clinics offer packages for a certain number. You’ll need to decide how many embryos you can afford to test, balancing the desire for information with your budget. Ask for a detailed breakdown of costs before committing.

Previous IVF Cycles and Genetic History

If you’ve had previous miscarriages or failed transfers, you may be more inclined to test more embryos. Similarly, if you have a known chromosomal abnormality or are considering PGT-M (for single gene disorders), the number of embryos biopsied may be influenced by the need to find embryos that are both unaffected and chromosomally normal.

How Many Embryos Do You Need? A Decision Framework

There is no magic number, but you can approach the decision systematically:

1. Estimate your expected number of blastocysts: Based on your age, ovarian reserve, and previous cycles, your doctor can give you a rough estimate.
2. Consider your family goals: How many children do you hope to have? This affects how many normal embryos you might want.
3. Understand the probability: Ask your clinic for age-based statistics on the likelihood of a normal embryo, but remember these are population averages, not guarantees.
4. Set a budget: Determine how much you can spend on PGT-A and how many embryos that covers.
5. Discuss with your clinic: Some clinics have policies on minimum or maximum numbers for biopsy. Ask about their experience and recommendations.

Questions to Ask Your Clinic

• How many embryos do you recommend biopsying in my situation, and why?
• What is the cost per embryo for PGT-A, and are there package deals?
• What is your policy on biopsying lower-grade embryos?
• How many embryos typically reach the blastocyst stage for someone my age?
• What is the turnaround time for results, and how does that affect my cycle?

Next Steps: Making Your Decision

Deciding how many embryos to biopsy is a personal choice. Take your time, gather information, and consult with your fertility team. Remember that PGT-A is a screening tool, not a guarantee of pregnancy or a healthy baby. It can reduce the risk of transferring an abnormal embryo, but it doesn’t eliminate all risks.

For more information on PGT in Thailand, see our PGT in Thailand guide. You may also find our other guides and FAQ helpful.

Frequently asked questions

Is there a minimum number of embryos required for PGT-A?

Some clinics may have a minimum number of embryos they recommend for biopsy, often around 3-5, to increase the chance of finding a normal embryo. However, this is not a universal rule. You should ask your clinic about their specific policy and how it applies to your situation.

Can I biopsy only one embryo for PGT-A?

Technically, you can biopsy a single embryo, but it may not be cost-effective or informative. If you have only one embryo, testing it can still provide valuable information, but you should discuss the likelihood of it being normal with your doctor.

Does embryo quality affect the number I should biopsy?

Yes, embryo quality can influence the decision. Higher-quality embryos are more likely to be normal, so you might need fewer to find a normal one. However, even high-quality embryos can be abnormal, so some clinics recommend testing all available blastocysts.

How does age affect the number of embryos to biopsy?

As age increases, the percentage of normal embryos typically decreases. Therefore, older women may need to biopsy more embryos to have a reasonable chance of finding at least one normal embryo. Your doctor can provide age-specific estimates.

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.