Egg freezing is a relatively new procedure where a woman’s eggs are collected, frozen, and stored with the intention of later use.
Women who are not yet ready to start a family may choose to freeze their eggs to keep the option on the table for longer.
There has been significant promise, but also significant disappointment, with egg freezing to date. The disappointment stems from the relative lack of success rate data. Many more women are freezing eggs than thawing them. And until they are thawed, how do we know how successful the treatment really was?
At first, the data was generally only coming from egg donors, women pre-selected to have eggs that would be expected to succeed. Significantly less data was available for “social” egg freezing, that is, women who are choosing to delay their reproduction and hope to be able to freeze their eggs in time. The majority of our patients were waiting for the latter data sets to come through, as we tried to keep expectations firmly in check.
We are now finally seeing the numbers, and it appears that for most patients egg freezing works as well as embryo freezing, with success rates often in the range of 60% (see this article for more). This published data fit our internal data suggesting clinical pregnancy rates 55-60% per set of eggs for women under 38.
Egg freezing is promising when we have enough good eggs to freeze. If you are under 38 years old (age being a marker for egg quality) and have been told you should be able to freeze 12-20 mature eggs (ie. you have a good ovarian reserve), and are working with a good lab able to offer vitrification, you may anticipate having three or more fertilized egg develop to blastocysts and a reasonable expectation for pregnancy in the future. No, it isn’t perfect – all things being equal frozen eggs do not work as well as fresh eggs – but with good counselling egg freezing may provide some measure of reassurance that had been missing until now.