--- title: "Can frozen embryos get frostbite?" date: 2025-11-10 author: "HSFC Kenya" featured_image: "https://hsfckenya.com/wp-content/uploads/2026/07/Can-frozen-embryos-get-frostbite.png.webp" categories: - name: "Treatments and Services" url: "/resource-library/articles/category/treatments-and-services.md" --- # Can frozen embryos get frostbite? Frozen embryos do not get frostbite. The freezing process, known as vitrification, uses special techniques to protect the embryos at extremely low, stable temperatures, which prevents the cellular damage that causes frostbite in living tissue. **Why embryos do not get frostbite** - **Cryoprotectant agents (CPAs):** Before vitrification, the embryo is treated with CPAs, a type of “antifreeze”. These chemicals draw water out of the cells and replace it with a protective fluid, which prevents harmful ice crystals from forming. - **Vitrification, not freezing:** The process is more accurately described as “vitrification,” or flash-freezing. The embryo is cooled so rapidly that the water inside its cells turns into a glass-like solid instead of damaging ice crystals. - **Preventing cold shock:** During the older, “slow freezing” method, a process called “cold shock” could damage the embryo during the cooling phase. The modern vitrification technique prevents this by moving the embryo through temperature changes so rapidly that it bypasses the dangerous temperature zone. - **Extreme, stable cold:** Frozen embryos are stored in liquid nitrogen at a constant temperature of about −196∘𝐶 (or −321∘𝐹). At this temperature, all biological activity is paused, and the embryo is preserved indefinitely. In contrast, frostbite occurs when living tissue is exposed to freezing temperatures, causing damage from ice crystals and restricted blood flow. **Risks during freezing and thawing** While embryos don’t get frostbite, they can still be damaged during cryopreservation. The primary risk occurs during the freezing and thawing processes. - **Damage from ice crystals:** If an older or less effective freezing method is used, ice crystals can form, damaging or destroying the embryo. - **Cell damage:** Some embryos do not survive the freezing or thawing process. However, modern vitrification techniques have very high survival rates, often over 95%. - **Partial survival:** Even if some cells are lost during the process, it does not always mean the end of an embryo’s viability. Some embryos can partially survive and still successfully implant and develop. At the heart of the process is fertilisation and the creation of an embryo in the lab. Once an embryo reaches a certain developmental point, often the blastocyst stage, it can be carefully and swiftly frozen. **Why Freeze Embryos?** There are many motives: - In a typical in vitro fertilisation (IVF) cycle, stimulating the ovaries to produce many eggs often produces more embryos than can safely be transferred to the woman’s uterus at one time. Transferring high numbers of embryos creates a significant risk of multiple pregnancies, so selecting only the best one (or occasionally two) embryos to transfer is commonplace. Any additional good-quality embryos can then be frozen. These can then be thawed and transferred at a later date if the first cycle is not successful or if additional pregnancies are desired. - It is now quite common for the fertility doctor to recommend that we ‘freeze all’ suitable embryos in a cycle. This might be because the lining of the uterus is unsuitable for transfer, or it is hoped that the environment in the uterus in a later cycle might give a better chance of implantation. - All suitable embryos can also be frozen and used later if a woman is at risk of developing ovarian hyperstimulation syndrome (OHSS). ‘Freeze all’ is recommended in these circumstances because pregnancy can make OHSS much more severe. - Perhaps you’ve done an IVF cycle, produced good embryos, and storing them gives you future options without undergoing another full cycle. - Perhaps you and your partner want more flexibility over when to start or expand your family. - Perhaps medical treatments are imminent that could affect your fertility [chemotherapy](https://hsfckenya.com/resource-library/articles/dr-alfred-murage/fertility-preservation-in-the-face-of-cancer/), major surgery, or other interventions. Because of these reasons, embryo freezing shifts from being a “luxury” to a strategic, hopeful tool. **What the Evidence Shows** - Embryo thaw survival rates are very high when high-quality embryos are frozen under optimal conditions. - Because of freezing technology improvements, outcomes (pregnancies, live births) after frozen embryo transfer are comparable or better than those of fresh transfers. - Long-term storage does not seem to degrade embryo viability significantly, especially when methods follow the latest developments. - Nevertheless, success is still influenced by egg/embryo quality, age, uterine readiness, and myriad individual factors. Freezing isn’t a guaranteed “insurance policy,” but a strategic move. **Benefits & Considerations** **Benefits**: - Flexibility: Timing of [egg](https://hsfckenya.com/resource-library/articles/female-infertility/egg-freezing-vs-embryo-freezing-which-one-should-you-choose/) or sperm collection is not under pressure of fertilisation and transfer into the uterus. - Better timing: You can wait for optimal uterine conditions or for life circumstances to align. - Preservation: Especially valuable when fertility is threatened medically. **Considerations**: - Cost & logistics: Retrieval, freezing, storage, and thawing all have financial and emotional costs. - Emotional weight: Waiting with frozen embryos can bring hope and alleviate anxiety over outcomes. - Not foolproof: A frozen embryo still needs a successful transfer, implantation, and pregnancy journey. - Ethical, legal & planning considerations: Who has rights over frozen embryos? How long will you store them? What happens if circumstances change? **The Take-Away** Freezing embryos is a remarkable convergence of science, hope, and planning. It offers a chance to pause time in a fertility journey and gives more control over timing and readiness. But it’s not a guarantee that it works best when paired with strong fertility health, realistic expectations, and careful planning. For anyone navigating fertility options, remember: freezing embryos is not an end in itself, it’s a flexible strategy that requires thoughtful decision-making, strong clinical support, and emotional resilience. With that, it becomes a powerful chapter in your fertility story. Read more about embryo freezing in this [article](https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/freezing-embryos#:~:text=At%20this%20point%2C%20the%20highly,embryos%20survive%20the%20thawing%20process.) by Johns Hopkins Medicine. [Reach out to us](https://hsfckenya.com/contact-us/) to find out more about the option to freeze your embryos.