In the US, the average age of first birth has risen from 19 years old in 1984 to 30 years old in 2021, even higher in many metropolitan areas. Many people are delaying parenthood for many reasons, such as financial, professional, educational, and personal. Unfortunately, egg quality and quantity are likely to decrease with age, which can lead to infertility, adverse pregnancy outcomes, and the inability to achieve desired family size.
A study published in Fertility and Sterility looked into the “real life” outcomes of egg freezing to delay childbearing. This study had 543 patients. The average age of the first egg freeze was 38 (older than the optimal age, which is 35 or younger), with the median time between freezing and thawing being 4.2 years. Overall, between 2005-2020, there were 800 egg freezing cycles, 605 egg thaws, and 436 embryo transfers.
This study found that 70 percent of patients who froze their eggs aged 38 or younger and thawed out at least 20 years later had a baby. This percentage was a lot higher than those who used fresh eggs or embryos for in vitro fertilization (IVF) at age 40 – where 30 percent became pregnant and only 20 percent gave birth.
“Our findings shed light on the factors that track with successful births from egg freezing, which include careful screening of embryos to be thawed and implanted,” said study lead Sarah Druckenmiller Cascante in a statement. “A better understanding of the live birth rate from egg freezing for age-related fertility decline is necessary to inform patient decision-making.”
“Importantly, our study is based on actual clinical experience,” adds Cascante, “rather than mathematical modeling with limited data, which is most of what has been published on the chance of births from egg freezing thus far.”
One advantage of this method is that frozen and thawed embryos often undergo preimplantation genetic screening, resulting in lower miscarriage rates and higher live births per transfer. This type of screening also allows single embryo transfers, which is safer for parent and child.
“Our results provide realistic expectations for those considering oocyte preservation, and demonstrate that egg freezing technology empowers women with improved reproductive autonomy,” says study author James A. Grifo. “Freezing eggs at a young age becomes an option to be one’s own egg donor at advanced age. As younger patients freeze eggs and do more than one cycle, the success rates will be even higher than reported in this study.”
The NYU Langone Fertility Centre is a pioneer in the development of egg freezing technology, and saw the first baby born through egg freezing in 2005. They have seen almost triple the number of people starting egg freezing cycles in 2022 compared to 2019. This increase highlights the importance of this type of study so that patients can be better informed when seeking to secure their reproductive futures. Now, further larger studies are underway and additional studies need to be conducted across different geographic and center types.