When you’re comparing IVF clinics in Thailand, success rates are often the first number you look at. But those figures can be misleading if you don’t know how they’re calculated. Different clinics report different patient groups, use different embryo transfer policies, and may follow different reporting standards. This guide explains why success rates vary, what to look for, and what questions to ask before you make a decision.
At a glance: key points to remember
- Success rates depend heavily on patient age, diagnosis, and embryo quality.
- Clinics may report live birth rates, clinical pregnancy rates, or both—know the difference.
- Embryo transfer policies (fresh vs. frozen, single vs. multiple) affect success rates.
- Always ask for data specific to your age group and situation.
- Look for independent verification or accreditation, but confirm details directly.
Why published success rates can mislead
Success rates are not a simple score. They are influenced by many factors that may not be obvious from a single percentage. Here are the main reasons why comparing rates across clinics can be misleading.
Patient demographics and selection
Clinics that treat younger patients or those with less complex fertility issues will naturally have higher success rates. Some clinics may also decline to treat patients with poor prognoses, which can inflate their reported success. Always ask for data broken down by age group and diagnosis.
Embryo transfer policies
Transferring multiple embryos increases the chance of pregnancy per cycle but also raises the risk of multiples. Some clinics favor single embryo transfer (SET), which may lower per-cycle success but is safer for mother and baby. Compare like with like: ask about the clinic’s policy on fresh vs. frozen transfers and single vs. multiple embryo transfer.
Reporting standards and definitions
Success can be reported as biochemical pregnancy, clinical pregnancy (heartbeat seen on ultrasound), or live birth. Live birth is the most meaningful outcome, but not all clinics report it. Also, some clinics report rates per egg retrieval, while others report per embryo transfer. Make sure you know which denominator is used.
How to compare clinics fairly
To make a meaningful comparison, you need to standardize the data as much as possible. Here’s a step-by-step approach.
Step 1: Ask for age-specific live birth rates
Request live birth rates per cycle for your age group (e.g., under 35, 35-37, 38-40, over 40). If a clinic doesn’t provide this, ask why.
Step 2: Understand the cycle type
Ask whether the rates are for fresh cycles, frozen embryo transfers, or all cycles combined. Frozen transfers are increasingly common and may have different success rates.
Step 3: Check the time period
Success rates can change over time. Ask for the most recent data and whether it covers a full year or longer. Be wary of very small sample sizes.
Step 4: Look for independent verification
Some clinics may have their data audited by a professional body. Ask if their data is verified and by whom. However, even without external verification, you can still ask detailed questions.
Questions to ask a clinic about their success rates
When you contact a clinic, ask these specific questions to get a clearer picture.
- What is your live birth rate per cycle for my age group?
- Do you report clinical pregnancy rates as well? If so, what is the difference?
- What is your policy on single vs. multiple embryo transfer?
- Do you report fresh and frozen transfer outcomes separately?
- How many cycles did you perform in the last year for my age group?
- What is your cancellation rate before egg retrieval?
- How do you define a ‘cycle’ in your statistics?
- Do you have any independent audit of your data?
Other factors to consider beyond success rates
Success rates are important, but they are not the only factor in choosing a clinic. Consider the following as well.
Laboratory standards and technology
Ask about the embryology lab’s accreditation, the experience of the embryologists, and what technologies they use (e.g., time-lapse imaging, genetic testing). These can affect outcomes but are not always reflected in success rates.
Cost transparency
Understand what is included in the quoted price and what is extra. Ask about medication costs, lab fees, and any additional procedures. Compare total expected costs, not just the base package.
Patient support and communication
Consider how the clinic communicates with international patients. Is there a coordinator who speaks your language? How quickly do they respond to questions? Good communication can reduce stress during treatment.
Your next steps
Before you decide, take these steps:
- Shortlist 2-3 clinics that seem to meet your needs.
- Request their success rate data in writing, with the details mentioned above.
- Compare the data side by side, but remember that differences may be due to patient mix.
- Ask for a consultation to discuss your specific case and get a personalized assessment.
- Check if the clinic has any accreditations or affiliations, but verify directly.
Remember, success rates are a starting point, not the whole story. A clinic with a slightly lower rate but a more transparent approach may be a better fit for you.
For more guidance, explore our IVF success rates in Thailand overview, read our frequently asked questions, or browse our guides for more detailed information. If you have specific questions, feel free to contact us.
Frequently asked questions
Why do IVF success rates vary so much between clinics in Thailand?
Success rates vary because clinics treat different patient populations, use different embryo transfer policies, and may report outcomes differently. For example, a clinic that treats mostly younger patients or uses single embryo transfer may have different rates than one that treats older patients or transfers multiple embryos. Always ask for age-specific live birth rates and understand how the data is calculated.
What is the difference between clinical pregnancy rate and live birth rate?
Clinical pregnancy rate is the percentage of cycles that result in a pregnancy confirmed by ultrasound (usually a fetal heartbeat). Live birth rate is the percentage of cycles that result in a live birth. Live birth rate is a more meaningful measure of success because it accounts for miscarriages and stillbirths. Some clinics may report only clinical pregnancy rates, so ask for live birth data.
Should I compare fresh or frozen embryo transfer success rates?
It depends on your situation. Some clinics have higher success rates with frozen embryo transfers (FET) because the uterus can be better prepared and the embryo is transferred in a more natural cycle. Others may have similar rates. Ask for both fresh and frozen transfer outcomes to see which is better for your age and diagnosis.
How can I verify a clinic's success rate data?
Ask if the clinic's data is audited by an independent body, such as a national fertility registry or professional organization. However, not all clinics have external audits. You can also ask for detailed breakdowns by age and cycle type, and compare multiple clinics to see if the numbers are consistent. Be cautious of clinics that refuse to provide detailed data.
What other factors should I consider besides success rates?
Consider the clinic's laboratory standards, the experience of the medical team, the cost structure, and the level of support for international patients. Also, think about the clinic's policies on genetic testing, embryo freezing, and multiple births. A clinic with a slightly lower success rate but better communication and transparency may be a better choice for your overall experience.
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.