Egg freezing is no guarantee for future fertility

October 19, 2014Carole 5 Comments »

In 2013, the American Society for Reproductive Medicine (ASRM) declared that egg freezing was no longer experimental. Here is a link to the professional guidelines, which say in part: “There is good evidence that fertilization and pregnancy rates are similar to IVF/ICSI with fresh oocytes when vitrified/warmed oocytes are used as part of IVF/ICSI for young women. Although data are limited, no increase in chromosomal abnormalities, birth defects, and developmental deficits has been reported in the offspring born from cryopreserved oocytes when compared to pregnancies from conventional IVF/ICSI and the general population. Evidence indicates that oocyte vitrification and warming should no longer be considered experimental.”

I have highlighted some important caveats to this declaration.

  • The method of freezing makes a difference. Old-style slow freezing is not included because most US labs never demonstrated that slow egg freezing could repeatedly be performed with good results- although some Italian labs were successful with slow egg freezing. Vitrification is not considered experimental- when done expertly.
  • To get the best fertilization results, thawed eggs must be fertilized using ICSI (aka. egg injection) because the egg membranes harden and sperm in culture have a very difficult time pushing their way in to fertilize the egg; the sperm must be injected using a microscopic needle.
  • Outcome data are limited regarding whether the resulting offspring are normal but early results are encouraging.

If you read the entire document- which I strongly encourage you to do if you are thinking about egg freezing- you will notice that the authors raise the issue of generalizability of these results to all labs everywhere. The pregnancy data that was referenced was all from the frontier labs who took this method up as a major initiative in their lab and really worked hard to get those positive results. Even with vitrification, egg freezing is not an easy technique. It does not take long to do but in that short time between immersing an egg into toxic cryopreservation fluids, and plunging the container with the egg into liquid nitrogen, there are about twenty different ways to make a mistake and little or no time to fix it so you better be both fast and good at the hand work. That takes both excellent training and practice. This is made more complicated because there are about 10 different containers to freeze eggs in and various kinds of vitrification medium being produced by different companies all vying to tell labs that their method/media/container is the best. So it is not like there is one obvious best method that all labs can just get busy and learn to do well. There is no obvious best standard of care.

In one of my labs, we had great difficulty in reproducibly getting good results with vitrification even though our pregnancy rates with IVF and FET cycles were the best in the state. This is evidence that just because you have mastered one skill set, doesn’t mean that a new technique won’t require significant time and effort to master.  So when the “experimental” label was removed from egg freezing, my first reaction was dismay because I knew that a lot of clinics would recognize an opportunity to offer a new service –and make a lot of money–without necessarily making the investment in staff and training to do it expertly. A lot of first patients at these rush-to-offer egg freezing clinics would be guinea pigs who would happily pay their money and not know whether they had gotten any value for years.

So how are clinics doing? Nobody really knows- it’s not currently part of the data set that must be reported to the CDC- but that will change in the future.  Sure, good clinics are tracking their data internally now but until you thaw (warm) an egg and try to fertilize it and grow it to a blastocyst stage embryo for transfer, you have no idea whether the vitrification and warming worked and your egg is still alive and functional.  Women who are freezing for the future aren’t going to even try to use those eggs for years, so actually getting pregnancy data from vitrified eggs will be slow in coming– making it hard  today for patients to distinguish good egg freezing programs from bad egg freezing programs.

Now Apple and Facebook are covering egg freezing as a benefit for the employees. On the one hand, it is a great thing to remove barriers from reproduction for people who want to have kids. But the potential harm here is that women will think egg freezing is a slam dunk- and that by freezing eggs now, they have a guarantee that they will have functional eggs for producing a pregnancy in the future. I wouldn’t make that bet right now unless your program can prove to you that it has pregnancy outcome data from many, many patients who successfully used their vitrified eggs and are now happily raising these kids.

I know of at least one program that crowed about their success with achieving a single pregnancy from a vitrified egg but then failed to reproduce that event for another patient for months! Actually, I don’t know if they ever did have a second birth. They didn’t believe in writing down their methods so they couldn’t reproduce their success.  That didn’t stop them from aggressively marketing that first pregnancy using every social and media outlet they could find. I am sorry for all the women who went to that clinic based on one case. Yes, eggs were put in storage for the patients the marketing brought in, but there is no guarantee that they can rely on those eggs when they need them. And by the time those thaws happen in any real numbers and patients are unhappy, the greedy bastards who froze their eggs will have retired.

My advice to young women is that they should really push for pregnancy data from any clinic that wants to sell them egg freezing. Unless the clinic can document in writing that their birth rate for women of your age using frozen eggs are are no different than same-aged women using fresh eggs – AND- they have hundreds of successful pregnancies, not just one – don’t use their clinic. And don’t be fooled by their pregnancy data with embryo freezing. Embryo freezing is about 100 times easier than egg freezing so the success rates for one doesn’t necessarily translate into success rates for the other.

If your employer is paying for egg freezing, it’s a good idea to make sure your employer is also paying for annual storage fees and the IVF cycle(s) you’ll need in the future to actually use your frozen eggs.




© 2014, Carole. All rights reserved.

5 Responses to this entry

  • Sarah Says:

    The more I read about this egg freezing “insurance” the more it angers me. How come for a single IVF cycle a live birth is ca. 35 percent in under 35s and for IVF they recommend 3 cycles for a >75 percent chance of baby. This would equate to 30-45 eggs yet with egg freezing they are saying 10-15 eggs is a good insurance??!! I think unless you know a lot about IVF you just don’t have a clue if the attrition rate! I’m a few years time these poor women are likely still going to be child free when they come to unfreeze their eggs….

  • Carole Says:

    Hi Sarah,
    Yes, I am worried that we will see a backlash against egg freezing in a few years when some patients are disappointed. I wonder if some companies who offer this “benefit” are just cynical enough to giving patients a false sense of security- just to keep those young women working and delaying child birth as long as possible…or the more charitable explanation is that they have also been duped into thinking egg freezing is more of a guarantee than it actually is. Your best bet –if you want to avoid the infertility doctor–is to have children before age 35 if at all possible. Egg freezing/thawing and IVF needs to get a lot better before it can be considered “insurance” for delaying reproduction. Carole

  • Nathalie Says:

    Dear Carole,

    Thank you very much for your blog, which I wish I had found sooner. I have read your posts about the great difficulty of freezing eggs well and have a question regarding your opinion on specific labs’ egg freezing abilities. Due to staying in relationships that didn’t lead to marriage much longer than I probably should have, I started freezing my eggs shortly after my 38th birthday and have since done three additional cycles (I am now 41 and 8 months). My first cycle was at Fertility Centers of Illinois and my last three were at Shady Grove Fertility in Chesterbrook, PA. All four cycles were vitrification, not slow freeze. Do you know anything about these labs’ expertise in freezing eggs as opposed to embryos? I did at one point consider NYU because as far as I can tell they have the greatest number of cases that have resulted in live births, but they were so much more expensive than my other options. Thank you in advance for your input.

  • Carole Says:

    Hi Nathalie,
    You might find this past blog post on finding a good egg freezing clinic useful Please don’t beat yourself up for past choices in life– hang in there! There are many paths to parenthood. Good Luck! Carole

  • Nathalie Says:

    Thank you, Carole. I really appreciate it.

Join the discussion