At a glance
Frozen embryo transfer (FET) success rates in Thailand vary by clinic, patient age, embryo quality, and other factors. This guide explains what influences outcomes and what questions to ask.
Understanding Frozen Embryo Transfer Success Rates
Frozen embryo transfer (FET) is a common procedure where a previously frozen embryo is thawed and transferred into the uterus. Success rates for FET in Thailand are generally comparable to international standards, but they depend on several individual factors. Because no single number applies to everyone, it is important to understand what influences outcomes and how to interpret clinic-reported data.
At a Glance: Key Factors in FET Success
- Embryo quality: Genetically normal (euploid) embryos have higher implantation potential.
- Patient age: Younger patients typically have higher success rates due to better egg quality.
- Uterine receptivity: Endometrial thickness, pattern, and timing of transfer matter.
- Clinic protocols: Laboratory standards, freezing techniques (vitrification), and transfer expertise vary.
- Number of prior transfers: Success may decrease after repeated failures.
Factors That Affect FET Success
Embryo Quality and Genetic Testing
Embryos that have undergone preimplantation genetic testing (PGT) and are found to be chromosomally normal (euploid) have a higher chance of implantation. Many Thai clinics offer PGT, but not all embryos are tested. Ask your clinic about their embryo grading system and whether PGT is recommended for your situation.
Patient Age
Age is one of the strongest predictors of IVF success. Women under 35 generally have higher live birth rates per transfer compared to women over 40. However, using donor eggs or previously frozen embryos from a younger age can offset age-related decline.
Uterine Receptivity
The endometrium must be receptive for implantation. Clinics assess endometrial thickness (typically 7-14 mm), pattern, and blood flow. Some offer endometrial receptivity array (ERA) testing to determine the optimal timing for transfer, though its routine use is debated.
Clinic and Laboratory Standards
Success rates can vary between clinics due to differences in embryology lab quality, freezing protocols (vitrification vs. slow freezing), and transfer technique. Vitrification is now standard and yields high survival rates for frozen embryos.
How to Interpret Clinic Success Rates
Thai clinics may report success rates in different ways: per embryo transfer, per cycle started, or per patient. Some report clinical pregnancy (heartbeat on ultrasound), while others report live birth. Always ask for live birth rates per transfer for patients in your age group and with similar embryo status (e.g., PGT-tested or untested).
Be cautious of rates that seem unusually high; they may reflect a selected patient population. National averages are not published by a single authority, so comparing clinics requires careful questioning.
Questions to Ask Your Clinic About FET Success
- What is your live birth rate per frozen embryo transfer for patients in my age group?
- Do you report outcomes for PGT-tested embryos separately?
- What is your embryo survival rate after thawing?
- Do you use vitrification for all embryos?
- What is your policy on single vs. multiple embryo transfer?
- Do you offer ERA testing or other endometrial assessments?
Next Steps for Patients Considering FET in Thailand
- Gather your medical history, including previous IVF cycles and any genetic testing results.
- Research clinics that specialize in FET and have transparent success data.
- Schedule consultations to discuss your individual prognosis and ask the questions above.
- Confirm the total cost of a frozen embryo transfer cycle, including medications, monitoring, and the transfer procedure.
- Plan for travel and accommodation if you are an international patient; some clinics offer coordination services.
For more detailed guidance, explore our FAQ section and patient guides. If you need personalized assistance, contact our team.
Frequently asked questions
What is a good success rate for frozen embryo transfer?
A good success rate depends on your age and embryo quality. For women under 35 using a genetically normal embryo, live birth rates per transfer can exceed 50-60% in experienced clinics. For women over 40, rates are lower, often 20-30% per transfer. Always ask your clinic for their specific data.
Is frozen embryo transfer more successful than fresh transfer?
For many patients, FET success rates are similar to or slightly higher than fresh transfer, especially when embryos are genetically tested. FET allows time for uterine preparation and avoids ovarian stimulation effects on the endometrium. Your doctor can advise which approach is better for you.
Does embryo freezing affect success rates?
Modern vitrification techniques have very high embryo survival rates (over 90%) and do not significantly reduce implantation potential. The quality of the embryo before freezing is more important than the freezing process itself.
How many frozen embryos are typically needed for one live birth?
This varies widely. Some patients achieve pregnancy with one embryo, while others may need multiple transfers. On average, 2-3 transfers may be needed per live birth, but this depends on embryo quality and patient factors.
Can I choose the gender of my embryo with FET in Thailand?
Gender selection is legally restricted in Thailand. Some clinics may offer PGT for medical reasons, but elective sex selection is not permitted. Confirm the legal status with your clinic before proceeding.
Continue your research
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.
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