Pros and Cons: Should I Freeze Eggs or Embryos?
Embryo freezing is an established technique involving freezing your eggs once they have already been fertilized sperm. This has some advantages and some drawbacks. If you are considering freezing embryos, there are some very important things to consider before doing so. The decision to freeze embryos comes with clinical, personal, and potentially legal ramifications that might be difficult to grapple with now but could save you a lot of trouble in the future.
In terms of the process, embryo freezing is exactly the same as egg freezing except that after your eggs are retrieved, they would be fertilized with sperm in a lab, which would hopefully continue to develop into embryos before they are frozen - essentially completing two-thirds of the process of a full IVF cycle. In an egg freezing cycle, you would only have completed the first third of the process, leaving fertilization until the time you want to use them.
Is the success rate better?
The biggest misconception about freezing embryos is the success rate. Because an embryo is more fully formed than an egg, it’s considered less delicate. In the past, this equated to a higher likelihood that it would thaw correctly from its frozen state. However, with the development of the fast freezing technique called vitrification, thaw rates of eggs are almost exactly the same as embryos now - roughly 90% for eggs and 95% for embryos.
But, let’s be clear, that doesn’t mean your chances of achieving a successful live birth are 5% higher, it just means that embryos are a tiny bit more likely to make it to the next phase of the IVF process. And, the higher quality eggs that are frozen (i.e. if you freeze your eggs relatively young and maintain a healthy lifestyle), the more likely those thaw rates could be just as good, if not higher than that of embryos.
What all that being said, if you are freezing eggs later in life and you have a known “sperm source” (that’s not a great term, is it? But it’s the politically correct way of saying person or donor with whom you definitely want to make babies in the future!), then even this small bit of an advantage might make sense to you. This is something to discuss with your doctor. Whichever option you choose, prepare for the fact that only a percentage of your eggs will actually produce embryos, and even those might not implant successfully.
What are the benefits of freezing embryos?
Arguably the biggest benefit of freezing embryos is simply having more data to work with. With egg freezing, you want to get as many eggs as possible in the hopes that at least one of them will become a healthy baby. In the case of freezing embryos, you’ll be able to get a much better idea how many of those eggs are actually good quality. If it’s not a satisfactory number, you could then plan accordingly - let’s say move forward your plans for trying naturally, or do another cycle of ovarian stimulation right away.
Keep in mind that not all of your eggs will become embryos. And from there, you can choose to test your remaining embryos for chromosomal abnormalities. So by the time all that is said and done, you’ll have a pretty good idea what your chances of success will be in the future. Didn’t get the number of embryos you wanted? Now you can make a more informed decision as to whether or not to do another cycle, especially in your more fertile years.
“Whenever I speak with a patient that is married or in a seriously committed relationship but they are just not ready to start a family, I always recommend consideration of banking fertilized eggs – embryo banking. They survive thawing at a slightly higher rate and can be tested for their chromosomes at the time of freezing so they are so much closer to being a baby.” - Dr. Carolyn Givens, Pacific Fertility Center, San Francisco
What are the potential drawbacks of freezing embryos?
There is far more potential for both ethical dilemmas around their storage and fate (some people and countries have religious or moral objections or laws) and fewer issues surrounding “ownership.” Decisions over the fate of stored embryos can also lead to major disagreements or legal disputes, particularly in the case of divorce or separation.
Ultimately, once your egg is fertilized by sperm, it will always carry those genetics - there’s no going back. So your relationship with the owner of that sperm (and potential co-owner of the embryo) needs to be really clear.
“I always review the tradeoffs of freezing eggs versus embryos. In general, I counsel women that freezing eggs provides her with more flexibility and the outcomes are similar to freezing embryos.” - Dr. Meera Shah, NOVA IVF, Mountain View
Let’s take a few examples. Perhaps you’re in a new but promising relationship, or a steady long-term relationship, perhaps you’re even married, freezing embryos can seem like an exciting way to solidify your future family goals together. But what if something happens to either one of you or your relationship before you’d want to use them? And what if those embryos turned out to be your only chance of having your own biological child? This is very important to consider in case of a breakup, divorce or even an untimely death of your partner. It’s safe to assume that you don’t go into a relationship thinking any of these awful things will happen but it’s good to be realistic about any eventualities, as uncomfortable as they may be.
In one cautionary tale, a couple from Arizona chose to freeze embryos before one of them, Ruby, underwent chemotherapy and radiation treatment for breast cancer. Years later, at age 37, Ruby’s marriage fell apart. During the divorce proceedings, she requested to use her embryos because it was probably her only chance at having her own biological children; however, her soon-to-be-ex-husband rejected the request, as he no longer had no interest in having children with her.
In another high profile case, Modern Family actress Sofia Vergara has been entrenched in a long legal battle over the rights to her frozen embryos. In this case, her ex husband wants to use them with the help of a surrogate. There’s undeniable complex political elements to the legal debate, rooted in the battle over reproductive freedoms. Vergara’s ex expressed his opinion in a New York Times op-ed piece: “Shouldn’t a man who is willing to take on all parental responsibilities be similarly entitled to bring his embryos to term even if the woman objects? These are issues that, unlike abortion, have nothing to do with the rights over one’s own body, and everything to do with a parent’s right to protect the life of his or her unborn child."
Each US state approaches their handling of these cases differently. Most often, courts weigh in support of the person that does not want the embryos used; however, at least in Arizona, courts are leaning towards the person that intends to help the embryos “develop to birth.” There’s no really clear legal structure, though contracting carefully in advance with the help of a lawyer might be helpful. The point is that, when you look at these cases, it makes you realize you have to be really sure that linking that particular sperm to your eggs (which could one day represent your only shot at becoming a Mom) is the right idea, especially if you wait to use them past your most fertile years. And, if anything were to happen to your partner, it’s worth asking yourself if you’d still want to use those embryos, particularly if you had a new partner on the scene.
It’s a really complex thing, because you’re dealing with a big blank where the future sits, none of us really know what curveballs lie ahead, however happy we might feel now. Because of the legal and emotional risks as well as the limitations placed on your reproductive autonomy, many doctors recommend seeing a couples counselor before following through with your decision.
“Before my second round of egg freezing, my partner and I talked about whether to freeze eggs or embryos. He was open to embryo freezing, but I decided to freeze eggs for a few different reasons. The first was as it felt like the decision that protected my independence and empowered me as a women the most in the long run. Despite the fact that I’m in a committed, loving relationship with a person that I hope to grow old with, the reality is that relationships end, people get divorced and people die. Secondly, although as a couple we are ready to commit to each other, we’re not necessarily ready to commit to having a child together and we were suddenly confronted with all kinds of ethical questions that we were not ready to answer. For example, if we decide to go our separate ways or one of us dies, who gets to decide what happens with the embryo given that both sets of our DNA are at play here? How do we feel about donating the embryos or discarding them? We decided that as soon as we were ready to commit to having children together we would freeze an embryo(s) then, taking further proactive steps towards family planning.” - Erika, 37
EXPERT PERSPECTIVE: “I recently met with a couple that had been together for a long time. She was ready to get married and have babies but he wasn’t. She was 39, so it made sense for her to freeze her eggs in the meantime, but when she brought up freezing embryos, he didn’t want to commit. I referred them to a couples’ counselor, which I think has been really helpful for them. Because of her age, she decided to freeze her eggs now and then do an embryo freezing cycle later if the counseling goes well.” - Peggy Orlin, Marriage & Family Therapist
Is there a cost difference?
An important thing to factor into this is the relative cost of both options, too. If you choose to freeze embryos, you’ll have to pay more up front to have your eggs fertilized and genetically tested, which is a cost that you wouldn’t have to bear if you don’t end up using them at all. On the other hand, if you are able to get all the embryo testing done up front and discover that you have to do another cycle, this could save you from doing multiple rounds of IVF using your older, fresh eggs down the line, if you do need to use them. Many of these considerations will be more or less pertinent depending on the age you are now, when you would want to use them and how confident you are that you’ll use them in the future.