You've been preparing for this moment for months. Your surrogate's uterine lining is perfectly primed, medications are on schedule, and the transfer date is circled on your calendar. Then your fertility clinic calls with news you weren't expecting: your embryo didn't survive the thawing process.
It's a gut punch. And if you've never heard of thaw failure before, it can feel even more disorienting. But here's what you need to know upfront: this is rare with modern technology, it's not anyone's fault, and there is a path forward.
Key Takeaways
- Modern vitrification gives frozen blastocysts a survival rate of 95–99%+. Thaw failure is rare.
- Thaw failure is not anyone's fault — not yours, not your surrogate's, not your clinic's. It's a small, inherent risk of the cryopreservation process.
- Your FET consent form is your backup plan. Fill it out thoughtfully, specifying which embryo to thaw next and whether the clinic should proceed without waiting for additional instructions.
- If you have remaining embryos, the transfer can usually proceed the same day as planned — with minimal delay and minimal extra cost.
- If this was your only embryo, options include a new IVF cycle, donor eggs or embryos, or simply taking time to regroup.
- Your feelings matter. Disappointment, frustration, and grief are all valid responses, and support is available.
- Ask your clinic for their thaw survival rate. It's one of the most practical questions you can ask when choosing or evaluating a fertility clinic.
How Common Is Thaw Failure?
The short answer: not very common at all.
Today, virtually all reputable IVF clinics use a technique called vitrification — an ultra-rapid freezing method that cools embryos so quickly that ice crystals (which can damage cells) don't have a chance to form. With vitrification, blastocyst survival rates after thawing typically exceed 95%, and many leading clinics report survival rates above 99%. A large-scale 2026 study analyzing over 3,000 vitrified blastocyst transfers confirmed post-warming survival rates exceeding 99% across the board.
This is a dramatic improvement from older slow-freezing methods, where survival rates were closer to 80–85%. If your clinic has been in operation for many years, you might come across outdated statistics that sound alarming — but those numbers reflect a technology that has largely been replaced.
That said, a 95–99% survival rate is not 100%. If you have multiple embryos frozen, or if you go through several transfer cycles, the small probability of a thaw failure becomes more real. It's a low-risk event, but it's not a zero-risk event.
Why Does It Happen?
When an embryo doesn't survive the thaw, it's natural to want to know why. In most cases, there's no single clear-cut answer, but a few factors can play a role:
The embryo's inherent quality. Not all embryos are created equal. Some may have subtle cellular vulnerabilities that existed before freezing — factors that aren't always visible under a microscope but can affect how well the embryo tolerates the freezing and thawing process.
The freezing and thawing process itself. Even with vitrification, the process of cooling cells to −196°C and then bringing them back to body temperature is biologically demanding. In rare cases, cell membranes or internal structures can be damaged during this transition.
The embryo's developmental stage at the time of freezing. Blastocysts (Day 5–6 embryos) generally tolerate vitrification extremely well, but outcomes can vary slightly depending on the embryo's exact stage and expansion at the time of cryopreservation.
Here's the most important takeaway: thaw failure is not a reflection of something you did wrong. It's not caused by anything the intended parents, the surrogate, or the clinic did or didn't do. It's an inherent, small risk of the cryopreservation process.
You May Have Already Planned for This — On Your Consent Form
Here's something that might surprise you: most IVF clinics actually ask you to think about this scenario before it happens.
When you prepare for a frozen embryo transfer (FET), your clinic will typically ask you and your partner to sign a consent form. Among the many questions on that form, you'll usually find one that asks: If the embryo selected for this transfer does not survive the thaw, what would you like us to do?
If you have additional frozen embryos, the form will ask which embryo should be thawed next — and whether you'd like the clinic to proceed with thawing a backup embryo on the same day, or wait for further instructions. Some clinics also ask about your preferences regarding the order in which embryos should be thawed, especially if your embryos vary in quality grade or PGT-A testing results.
This consent step exists precisely because thaw failure, while rare, is a known possibility. If you haven't gone through the FET consent process yet, this is a good conversation to have with your fertility doctor ahead of time. Knowing your preferences in advance means that if the situation does arise, your clinical team can act quickly — potentially saving valuable time in your surrogate's transfer window.
A tip for intended parents in surrogacy: Because surrogacy involves coordinating between multiple parties — your clinic, your surrogacy agency, and your surrogate — it's especially important to have a clear backup plan documented. Your surrogacy coordinator at Ivy Surrogacy can help you think through these scenarios in advance, so no one is caught off guard.
What Happens Next?
If your embryo doesn't survive the thaw, the next steps depend on your specific situation.
If you have remaining frozen embryos
This is the more straightforward scenario. As long as your FET consent form has already specified your backup plan — which embryo to thaw next and authorization to proceed — your clinic can simply thaw the next embryo and move forward with the transfer as scheduled. Your surrogate's uterine lining is already prepared, and the transfer can typically happen the same day as originally planned. In most cases, the only difference is a short wait while the backup embryo is thawed and assessed.
This is exactly why the consent form matters so much. When your preferences are clearly documented in advance, the clinical team doesn't need to pause and track you down for instructions. They can act immediately, keeping your surrogate's carefully timed transfer window on track.
The financial impact in this scenario is generally minimal — typically just an additional thawing fee. You won't need to restart your surrogate's medication cycle or reschedule the transfer.
If this was your last (or only) embryo
This is the harder situation, and it's okay to take a moment to absorb it. Losing your only remaining embryo to a failed thaw can feel devastating, especially if it took significant time, money, and emotional energy to create that embryo in the first place.
Your options at this point typically include:
- A new IVF cycle. You can go through another egg retrieval and fertilization cycle to create new embryos. This is the most common next step, though it does involve additional time (usually 2–3 months) and cost.
- Using donor eggs or donor embryos. If another full IVF cycle isn't feasible or desired, donor eggs or pre-made donor embryos can be an alternative path. Your clinic and your surrogacy agency can help you explore these options.
- Taking time to regroup. There's no rule that says you have to make a decision immediately. It's completely valid to take some time to process what happened before deciding on your next move.
Your fertility doctor, your surrogacy coordinator, and your support network are all there to help you evaluate your options and find the path that makes the most sense for your family.
The Emotional Side
Let's be honest: even when you understand the statistics, even when you know this is rare and not your fault, hearing that your embryo didn't make it is painful. For many intended parents — especially those who have been through a long fertility journey — each embryo represents hope, investment, and the possibility of a child.
You might feel sadness, frustration, anger, or even a sense of grief. All of these feelings are valid. You don't need to "get over it quickly" or immediately pivot to problem-solving mode.
It's also worth knowing that your surrogate may be feeling disappointed too. She's been preparing her body for this transfer, and she shares in the letdown when plans change unexpectedly. Keeping the lines of communication open — whether directly or through your surrogacy coordinator — can help everyone feel supported during this time.
If you find that the emotional weight of a failed thaw (or any part of your fertility and surrogacy journey) is becoming difficult to carry, consider speaking with a counselor who specializes in reproductive issues. Many fertility clinics have referrals available, and your surrogacy agency can also point you in the right direction.
Can You Reduce the Risk?
While you can't eliminate the risk of thaw failure entirely, there are a few things that can help:
Choose a clinic with strong cryopreservation outcomes. Don't be afraid to ask your fertility clinic directly: What is your blastocyst thaw survival rate? A well-performing lab using modern vitrification should be reporting survival rates of 95% or higher. This is a reasonable and important question for any intended parent to ask.
Freeze more embryos if possible. If your IVF cycle produces multiple viable embryos, having several frozen gives you a built-in safety net — not just for thaw failure, but for any transfer that doesn't result in pregnancy.
Confirm your clinic uses vitrification. The vast majority of modern fertility clinics have adopted vitrification as their standard freezing method. If you're working with a clinic that still uses older slow-freeze protocols, it's worth asking why — and whether vitrification is available.
Fill out your FET consent form thoughtfully. Take the time to discuss the consent form questions with your partner and your fertility doctor. Having a clear plan for embryo selection and backup thawing preferences can make a stressful moment much more manageable.
The Bottom Line
A frozen embryo not surviving the thaw is one of those things that most intended parents never have to deal with — but it's worth knowing about, just in case. Modern vitrification technology has made this an increasingly rare event, and even when it does happen, there are clear paths forward.
Being informed isn't about preparing for the worst. It's about walking into your surrogacy journey with your eyes open, feeling confident that you can handle whatever comes your way — because you can.
Frequently Asked Questions
1. How often do frozen embryos not survive the thaw?
With modern vitrification — the standard freezing technique used by virtually all reputable clinics today — blastocyst thaw survival rates are typically 95–99% or higher. Thaw failure happens in roughly 1–5% of cases. Older slow-freeze technology had lower survival rates (around 80–85%), but this method has largely been phased out.
2. Will I know before transfer day if my embryo survived?
Yes. Your clinic thaws the embryo before the scheduled transfer and assesses its survival and re-expansion. If the embryo hasn't survived, you'll be informed before the transfer procedure takes place — not after.
3. If my embryo doesn't survive, can another one be thawed the same day?
In most cases, yes — as long as you have additional frozen embryos and your FET consent form authorizes the clinic to proceed with a backup embryo. This is why filling out your consent form carefully is so important. With proper authorization in place, the clinic can thaw the next embryo and keep your transfer on schedule without needing to reach you for real-time decisions.
4. Does thaw failure mean something is wrong with my other frozen embryos?
No. Each embryo is an individual, and the fact that one didn't survive the thaw doesn't predict the outcome for your remaining embryos. Your other frozen embryos have the same high probability of surviving as before.
5. Is thaw failure the clinic's fault?
In the vast majority of cases, no. Thaw failure is an inherent, low-probability risk of cryopreservation that can occur even in the best laboratories with the most advanced protocols. That said, it's always reasonable to ask your clinic about their overall thaw survival rates to ensure they meet industry benchmarks.
6. What if I only had one embryo and it didn't survive?
This is understandably the most difficult scenario. Your options typically include pursuing another IVF cycle to create new embryos, considering donor eggs or donor embryos, or taking time to process and plan your next steps. Your fertility doctor and surrogacy coordinator can help you evaluate all the available paths forward.
7. Does freezing duration affect survival rates?
Research suggests that embryos frozen for extended periods — even up to 10 years — do not show a meaningful decline in thaw survival rates or live birth outcomes. A large 2024 study of nearly 58,000 vitrified blastocysts confirmed that storage duration had no significant impact on survival or pregnancy rates.
8. Can I do anything to prevent thaw failure?
You can't eliminate the risk entirely, but you can reduce it by choosing a clinic with strong cryopreservation outcomes (ask for their blastocyst thaw survival rate), confirming they use vitrification rather than slow-freeze methods, and — if possible — freezing multiple embryos to give yourself a safety net.
Ready to Take the Next Step in Your Surrogacy Journey?
At Ivy Surrogacy, we know that every detail matters — from choosing the right fertility clinic to making sure your consent forms reflect a thoughtful plan. Our team walks alongside you through every step of the surrogacy process, including the moments that feel uncertain.
Whether you're just starting to explore surrogacy, preparing for your first embryo transfer, or navigating an unexpected bump in the road, we're here for you.
📞 Schedule a free consultation to speak with our team, or reach out anytime at Contact@ivysurrogacy.com. Let's build your family — together.
References
- ASRM Practice Committee. (2021). A review of best practices of rapid-cooling vitrification for oocytes and embryos: a committee opinion. Fertility and Sterility, 115(4), 893–903.
- Cobo, A., et al. (2024). Embryo long-term storage does not affect ART outcome: analysis of 58,001 vitrified blastocysts over an 11-year period. American Journal of Obstetrics and Gynecology. DOI: 10.1016/j.ajog.2024.03.033.
- Yelke, H.K., et al. (2026). Improved clinical outcomes with one-step warming of vitrified blastocysts: a retrospective analysis of 3,167 transfers. Reproductive BioMedicine Online. DOI: 10.1016/j.rbmo.2026.104842.
- Rienzi, L., et al. (2017). Oocyte, embryo and blastocyst cryopreservation in ART: systematic review and meta-analysis comparing slow-freezing versus vitrification to produce evidence for the development of global guidance. Human Reproduction Update, 23(2), 139–155.
