In the UK, the storage limit for eggs frozen for social reasons is currently limited to ten years: too short for healthy young women wanting to preserve their opportunities to conceive later in life.
The age at which women are first becoming mothers in England and Wales, as well as many other Western countries, has risen significantly in recent decades. The average age of a women at the birth of her first child is now 28.6 years and over half of all live births in England and Wales are to mothers aged 30 and over.
Data released this year, from the HFEA (Human Fertilisation and Embryology Authority) show that the live birth rate per fresh embryo transfer in women aged 43-44, who are undergoing IVF using their own eggs and partners' sperm, is only 3 percent. This drops to 2 percent for women aged 45 years and older. Research suggests that if a couple want a family size of three children with 90 percent certainty and without use of assisted reproduction then they will need to start trying to conceive when the woman is about 23 years of age, this increases to 27 years for those who desire two children, and 32 years for those who only desire one child (Habbema et al, 2015).
Despite an increase in risks posed to mother and child, the shift to older motherhood shows little sign of changing and reflects a host of other social changes including the timing of relationships, career progression, increased debt accumulation and economic uncertainty and instability.
It is in this context that a new form of fertility preservation has emerged: social egg freezing. The first baby born from a frozen egg was reported in 1986 (Chen, 1986) using a process of slow freezing. This method of cryopreservation was fraught with difficulties but the development of vitrification in the mid-2000s increased the success of egg freezing. In 2013, the American Society for Reproductive Medicine (ASRM) lifted the experimental label applied to egg freezing, following four randomised controlled clinical trials (Cobo et al, 2008; Cobo et al, 2010a, Rienzi et al, 2010; Parmegiani et al, 2011), which suggested IVF using vitrified and then warmed eggs could produce similar fertilisation and pregnancy rates to IVF with fresh eggs (ASRM, 2013).
It did, however, caution against the widespread use of egg freezing to counteract age-related infertility, stating: 'Marketing this technology for the purpose of deferring childbearing may give women false hope and encourage women to delay childbearing.'
Since 2000, the HFEA has allowed the storage and use of frozen eggs in fertility treatment for patients receiving gonadotoxic therapies for cancer and other illnesses; individuals with health conditions which may result in premature menopause; individuals who ethically or morally object to the cryopreservation of embryos; people undergoing medical treatment for gender dysphoria; as well as in the storage of eggs for women who wish to defer childbearing.
In 2001, just 29 women underwent the procedure in the UK, however by 2014 this had risen to 816 women who froze their eggs in 890 cycles (some women went through more than one egg collection to bank additional eggs). The latest HFEA data shows that 1173 cycles were undertaken in 2016, which is a 10 percent increase from the previous year.
From the HFEA document Fertility Treatment 2014-2016: Trends and Figures
The HFEA data does not record the reasons for undertaking egg freezing (medical or social). However, anecdotal evidence from clinics on the number of women inquiring about the procedure for social reasons suggests this to be the principal driver for the significant increase in the use of this technology in the UK. Research examining social egg freezing has most commonly identified the lack of a suitable partner, a fear of running out of time to form the desired family, and a fear of future regret as driving women's use of this technology (Baldwin et al, 2018).
From a medical perspective, it is recommended that egg freezing is performed under the age of 35, but 68 percent of women freezing their eggs in the UK are over 35 (see figure below). Research shows that women do not come for egg freezing earlier because they are optimistic that they can achieve their childbearing goals within the three-year period they give themselves, typically between 34 and 38 years of age (te Keurst et al, 2016). Given that the efficacy of the technology reduces with age, the use of social egg freezing by women who have already experienced a substantial decrease in the quality and quantity of their eggs is problematic. Women who want to undergo egg freezing therefore need to be made aware of the treatments' success rates and their contingency on maternal age.
The British Fertility Society's Fertility Education Initiative advocates improving knowledge about age-related fertility decline (Harper et al, 2017). However, knowledge will not necessarily advance childbearing intentions to earlier reproductive years given the social and economic complexity within which reproductive decisions are made.
From the HFEA document Fertility Treatment 2014-2016: Trends and Figures
In the UK, the Human Fertilisation and Embryology (HFE) Act 2008 states that all gametes can be stored for up to ten years, but for medical egg storage and for sperm storage (for any reason):
'The 2009 Human Fertilisation and Embryology (Statutory Storage Period) Regulations provide a mechanism for successive 10-year extensions of storage, up to a maximum of 55 years.'
Currently, eggs frozen for social reasons cannot be extended for more than the initial 10-year period (see BioNews 868). The longer storage for sperm results in gender inequality. And the longer storage for eggs for one set of circumstances (medical) and not for another (social) introduces inequality among women that runs counter to reality all women face, namely that fertility decreases with age.
So if a woman of 25 freezes her eggs, she has to use these before she reaches age 35, which is younger than women often want to start their families. Considering the reasons women freeze their eggs, we would like to campaign for extending the social egg freezing storage limit to 55 years for all women. Extending the time limit in such a way would ensure parity between freezing eggs for social and medical reasons, and would eliminate the sex-based inequality between women and men for freezing eggs and sperm.
If you think that Parliament should change the HFE Act – please sign your name to this campaign by clicking here.
Supporters of this campaign - Kylie Baldwin, Adam Balen, Peter Bowen-Simpkins, Rachel Cutting, Sarah Franklin, Zeynep Gurtin, Joyce Harper, Jessica Hepburn, Nicky Hudson, Emily Jackson, Robin Lovell Badge, Geeta Nargund, Sarah Norcross, Allan Pacey, Lesley Regan, Dan Reisel, Tracey Sainsbury, Lucy Van de Wiel and Gabby Vautier.
Sources and References
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ASRM, The Practice Committees of the American Society for Reproductive Medicine and the Society for Assisted Reproductive Technology (2013) Mature oocyte cryopreservation: a guideline
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Baldwin, K et al (2018). Running out of time: Exploring women’s motivations for social egg freezing.
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Chen C (1986). Pregnancy after human oocyte cryopreservation
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Cobo, A. et al (2008) Comparison of concomitant outcome achieved with fresh and cryopreserved donor oocytes vitrified by the Cryotop method
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Cobo, A et al (2010) Use of cryo-banked oocytes in an ovum donation programme: a prospective, randomized, controlled, clinical trial
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Habbema, JDF et al. Realizing a desired family size: when should couples start?
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Harper, J et al (2017). The need to improve fertility awareness
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Parmegiani, L et al (2011). Efficiency of aseptic open vitrification and hermetical cryostorage of human oocytes
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HFEA. Fertility treatment 2014-2016 - trends and figures
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Rienzi, L et al (2010). Embryo development of fresh 'versus' vitrified metaphase II oocytes after ICSI: a prospective randomized sibling-oocyte study
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ter Keurst, A et al (2016). Women's intentions to use fertility preservation to prevent age-related fertility decline
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