Egg Freezing vs Embryo Freezing: Pros and Cons

Egg freezing and embryo freezing are both useful fertility procedures. Which one is right for you? Read on to learn the pros and cons of freezing embryos vs freezing eggs. 

By OBGYN and fertility expert, Dr Kenosha Gleaton

Considering your family planning options and wondering whether embryo or egg freezing is right for you? Let’s talk about the pros, cons, similarities, and differences of both. 

What is egg freezing?

Egg freezing, also known as oocyte cryopreservation (OC) is the process of extracting and freezing mature eggs to use at a later time. Egg freezing is used by many for a wide array of reasons, including illness, gender transitioning, declining fertility, gestational surrogacy, and so on. In order to freeze eggs, some testing and screening will likely be done to get an idea of the quantity and quality of eggs. Then ovarian stimulation will occur with the use of hormones and fertility drugs so that an egg retrieval can happen. Up to 15 eggs may be retrieved in one cycle and are then frozen and stored in a facility until they’re ready to be used. Want more details? Here’s a complete guide on egg freezing.

What is embryo freezing?

Embryo freezing, or embryo cryopreservation, is a somewhat similar procedure to egg freezing. The key difference is that eggs are first fertilized through a procedure like in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Just like egg freezing, there are many reasons someone may want to freeze embryos, and the process is relatively similar. Once the testing, medications, and egg retrieval have been completed, the eggs will be exposed to donor sperm or partner sperm in order to become fertilized. This is where the eggs turn into embryos and can be frozen in one of two stages, the cleavage stage (a 3 day embryo) or blastocyst stage (a 5 day embryo). Embryos are stored until they are ready for use in the future. 

Pros and cons of freezing eggs

All fertility treatments will have pros and cons, and it’s up to you and your healthcare provider to determine what procedures will work the best for your situation and goals. 

Pro: You’re in control 

Deciding to freeze eggs is a decision that only involves your genes. There’s no sperm required at the time of egg freezing, meaning it allows for options down the road. This is a huge plus if you’re single, still deciding on a sperm donor, and so on. The New England Journal of Medicine likes to call this “reproductive autonomy” and it definitely rings true—freezing eggs puts you in charge of your own reproductive journey. 

Pro: You’re (sort of) freezing time

It’s true that egg quality decreases as we age, specifically after the age of 35. If you are reaching that age soon, have been told by a fertility specialist that your eggs are of poor quality, or are worried about your future health for reasons such as cancer or another illness, freezing your eggs now can give you some peace of mind. Check out our guide to getting pregnant in your late 30s and early 40s. 

Natalist offers many products to support your fertility goals, including hormone tests, supplements for men and women, and more. 

Pro: Less cost upfront

When comparing the two options, egg freezing is likely to cost you less upfront than embryo freezing. This is because the cost of IVF isn’t yet a factor. This isn’t to say that freezing your eggs is a cheap option, as one cycle of egg freezing is still estimated to cost between $8,000 to $20,000 depending on the cost of your fertility testing, medications, and storage. With embryo freezing, you have the added cost of fertilizing the eggs in a lab, which can increase your cost by a few thousand dollars. This will still need to be done down the line if you end up thawing your frozen eggs, but you’ll have more time to save up for the added IVF costs when the time comes.

Con: Side effects and risks

The side effects and risks of the fertility medications, egg retrieval, and eventual IVF procedure are pretty similar for egg freezing and embryo freezing. The injectable drugs used for stimulating the uterus may cause side effects like swollen or painful ovaries, nausea, cramping, and potentially more severe side effects like blood clots and dehydration. 

Con:  Unknown viability

When it comes down to the viability of the retrieved eggs, it’s hard to know if they will be viable until after they are fertilized. Preimplantation genetic testing can be done on embryos, but not cells, which may lead to some disappointment down the road. On the bright side there are usually multiple eggs retrieved in one cycle, which gives you a greater chance of having viable eggs and eventually, healthy embryos. 

Pros and cons of freezing embryos

Pro: Potentially fewer egg retrievals needed

The great thing about IVF and genetic testing is that you will have an idea of how many fertilized eggs you have frozen. Egg freezing still has a high success rate of over 90%, but there is no guarantee that all the thawed eggs will successfully fertilize. This may reduce the amount of times egg retrieval occurs and could save time down the road. 

Pro: Preserve sperm and egg health

A huge positive when it comes to embryo freezing is that you know you’re preserving the health of the sperm and the egg. Aging does have an impact on fertility for men and women, and choosing to freeze an already fertilized egg can eliminate some of the risks associated with lower quality eggs, but also lower quality sperm. For example, research shows that babies born to older fathers are at risk of premature birth, infant mortality, seizures, and more. Evidence also shows that low egg quality can make it more difficult to have a successful pregnancy. Read more about age and male fertility or age and female fertility. 

Con: Sperm is necessary

I’m not saying this to be funny, but it is true. If you’re deciding to fertilize an egg and freeze the embryo, you’ll need to decide where the sperm is coming from. Whether this is a partner or a donor, you don’t have the option to change your mind down the line. This may not be a bad thing if your mind's been made on a donor or partner, but for those that are single or unsure about this decision, there is added pressure. 

Con: Moral considerations

Some faiths and individuals have a harder time with the use of embryos. This is a bit different from freezing unfertilized eggs that don’t have the potential of developing into a baby. If you are freezing embryos, you will also need to make decisions beforehand about how to go about discarding unused or unwanted embryos, donating them to science or to an embryo adoption program. Not to take away from the gravity of these decisions when it comes to egg freezing, but there does tend to be more weight in the decision when involving embryos. 

Key similarities and differences between embryo freezing and egg freezing

The process for egg and embryo freezing are very similar, the main difference is whether or not fertilization occurs before or after freezing. To summarize, here’s a breakdown of the key similarities and differences between the two.

Cost

Final cost of egg freezing and embryo freezing will differ depending on many factors, including where you live, storage costs, fertility testing, and more. With egg freezing, you likely will pay less upfront since you don’t have to pay for IVF at the time of egg retrieval and storage. This gives you more time to save for IVF costs down the road, but at the end of the day, if you end up pursuing IVF with your frozen eggs, the total cost will likely be similar. 

Storage

The length of time you’re able to store your frozen eggs or embryos is about the same, up to or even longer than 10 years. There have been successful pregnancies using eggs previously frozen for over 10 years, similar to frozen embryos. How long you can store them will depend on the facility you use and what they allow. 

Efficacy

This is the big question for many when weighing their options— is egg freezing or embryo freezing more effective? The general consensus is that there isn’t much of a difference at all between the two procedures. One study found the frozen embryo live birth rate to be around 44%, and another found the frozen egg live birth rate to be around 42%. Another retrospective cohort study comparing the two concluded that no significant differences were found in live birth rate or perinatal outcomes. Bottom line: research shows efficacy is about the same, and will depend on other factors like maternal age, egg and sperm health, and so on. 

Egg freezing and embryo freezing are both great options for family planning and can be useful for a variety of reasons. There are pros and cons to both, so be sure to look over all your options and talk through them with a healthcare provider, partner, or another loved one. If and when you make your decision, we’ll be here to support you. 

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