The largest known study of elective fertility preservation found that more women in the United States are freezing their eggs than ever before. However, only a small percentage of patients return to thaw these eggs in the hope of becoming pregnant.
The number of scheduled elective egg cryopreservation or egg freezing cycles across the country nearly quadrupled between 2014 and 2021, from 4,153 to 16,436. However, only 5.7 percent of these women returned to use their frozen eggs for in vitro fertilization (IVF) within the study’s 5- to 7-year follow-up period, researchers from the University of California, Los Angeles found.
THE peer reviewed studypublished online at American Journal of Obstetrics and Gynecology in August 2025, also revealed that women are starting to freeze their eggs at a younger age. The average age of elective egg retrieval patients decreased from 36 years in 2014 to 34.9 years in 2021. Return-to-use rates were higher among patients who were older when they had their eggs frozen. Among people who froze their eggs between the ages of 38 and 42, about 8% returned to use them.
Rewire News Group spoke with the study’s lead author, Dr. Mabel Leephysician of reproductive endocrinology and infertility at UCLA Health, to discuss what the findings mean for elective fertility preservation in the US today.
This interview was conducted via email in two separate exchanges. Responses have been combined and edited for length and clarity.
What do you think about the data showing that relatively few patients return to use their eggs?
We cannot predict future fertility and who will need or choose to use their cryopreserved eggs. Despite egg freezing, many patients will likely try to conceive naturally first and, unless they experience infertility or repeated pregnancy losses, may never need to use their cryopreserved eggs.
However, when the patients returned to warm their eggs, the results were reassuring and the cumulative live birth rates were comparable to the overall IVF results.
I think the findings of our study reflect that optional egg freezing is a way to increase the chance of pregnancy in the future — but it is by no means a guarantee of pregnancy.
What are some of the reasons behind the low egg utilization rate reported in the study?
Our study is limited by the short follow-up time. It has only been 13 years since planned oocyte cryopreservation became non-experimental and only 11 years since the national database SART-CORS [a national database that collates data on all assisted reproductive technology cycles] began to report cycles only for fertility preservation.
The follow-up time of 5–7 years … limits our analysis of oocyte warming to only oocyte freezing cycles that occurred between 2014 and 2016, which may lead to an underestimation of how many total people have returned to reheat their frozen eggs since 2014. For example, people who froze their eggs in 2018 and returned in 2021 will not be included. (Editor’s note: Other research shows that in the long term perhaps 21 percent of all patients who freeze their eggs eventually become pregnant with assistive technology.)
Additionally, we only focused on egg freezing solely for fertility preservation purposes. we excluded patients who froze their eggs for medical or cancer indications. These patients are more likely to need to return to use their eggs because of underlying conditions that affect their reproductive potential.
Tell me more about differences in reproductive behaviors by age or by other criteria such as education, income, generation and the like.
Although our study did not examine demographic factors other than race/ethnicity and geographic regions, it is well established in the literature that patients from higher socioeconomic backgrounds and higher levels of education are not only more likely to delay childbearingbut it is more likely to access assisted reproductive technologies.
The exponential increase in patients undergoing elective egg freezing and at younger ages suggests that there is wider acceptance and use of these technologies in younger generations compared to older generations.
What are some of the major technological advances that have helped improve preservation and post-thaw success rates?
The major technological advance that improved egg freezing success rates was the introduction of vitrification as a technique. (Editor’s note: Vitrification is an ultra-rapid cooling cryopreservation method that uses chemical solutions or cryoprotectants.)
Prior to vitrification, freezing techniques often resulted in oocyte damage. … The technique has greatly improved outcomes, with survival rates of over 90 percent. So far, evidence shows that human embryos and eggs can be cryopreserved indefinitely. Just a few months ago, a baby was born after using an embryo cryopreserved in 1994.
Is there anything else you want to add that I didn’t ask?
This is the largest US study to date of selective fertility preservation and provides insight into the clear shift in reproductive behavior as more women delay childbearing to pursue education, career and personal goals. In this context, egg freezing offers a powerful and effective form of reproductive autonomy and flexibility.
