Mapping the upturn in egg donation and egg freezing in the UK

What a difference a decade makes. When we opened London Egg Bank at Harley Street in 2013, egg donation in Britain was still a backwater treatment for infertility: domestically-sourced donor eggs were hard to find, with patients having few options but to travel to centres in Spain, Ukraine or Cyprus, where eggs were more plentiful. Treatment at home was sporadic, dependent only on fresh donor eggs, cycles synchronised between donor or sharer and recipient, and lengthy waiting-lists.

It was these discouragements which, ten years ago, we had hoped to reverse (see BioNews 723). Studies from Spain and Italy (where embryo freezing had been outlawed in 2004) had by then confirmed the viability of vitrified oocytes, with one landmark study published in Human Reproduction recommending that oocyte vitrification 'should be applied routinely for various indications'. As a result of these and other studies, and now with the unequivocal reliability of vitrification, we could argue in 2020 in a paper published by Reproductive Biomedicine Online that cryopreservation of eggs and embryos had changed the landscape of assisted reproduction with the 'demise of fresh treatment cycles'.

This change has been most dramatically seen – in Britain as elsewhere in the world – in embryo freezing and frozen/ thawed transfers. In its latest report on treatment trends in the UK, the Human Fertility and Embryology Authority (HFEA) noted that frozen embryo transfers had increased in use by 41 percent from 2017 to 2021, while fresh embryo transfers had decreased by eight percent. In the USA the Centers for Disease Control described the dramatic increase in embryo freezing, plotting a rise from almost zero frozen transfer cycles in 2007 to 65,840 in 2016. In preliminary world data for 2019, presented at this year's European Society of Human Reproduction and Embryology annual meeting, total frozen transfers had outstripped fresh by around 60 percent to 40 percent.

It was this confidence in cryopreservation which lay behind the remarkable upturn in egg donation and egg freezing treatments in the UK. It had also become more evident that success rates in women in their later reproductive years were far higher with donor eggs than with their own, which, with a greater prevalence of age-dependent infertility, had now made egg donation more attractive. Indeed, the above HFEA report shows that the average age of IVF patients in the UK has now increased to 36, around five years older than mothers who get pregnant naturally.

This widespread confidence in cryopreservation is also evident in the HFEA's support to extend the storage limit to 55 years, following a campaign led by the Progress Educational Trust (PET), the charity that publishes BioNews. This has increased patient autonomy and removed any time constraint on those with gametes and embryos in freeze-storage. However, as recent reports and several PET meetings have warned, this extended storage limit may put strain on storage facilities at the Times reported, and raise new patient questions on the disposal of their unused eggs – or as bioethicist Professor Guido Pennings has recently published in Reproductive Biomedicine Online, turn egg freezers into egg donors.

From our own perspective, the past ten years have attracted almost 100,000 online applications about egg freezing and donation, reflecting a high level of altruism, and seen almost 2000 babies born from vitrified oocytes (donor or own). As elsewhere, demand for donor eggs continues to rise, as more and more couples postpone their first pregnancies and become less able to conceive naturally. At the same time, we have seen a rising demand from UK women opting for elective egg freezing – often to offset the inevitable decline in female fertility after the age of 35. The increase in egg freezing procedures at our centre in London has been dramatic, up from just six treatments in 2012 to 186 in 2016, 309 in 2018 and 759 in 2022. Recent data from one US clinic indicate that 38 percent of women who chose to freeze their eggs for later use and returned for treatment had successful pregnancies. Our own results are in line with this, and now include at least six patients who have achieved a second successful birth from their initial egg collection.

However, while egg freezing was recently described by the HFEA as 'one of the fastest growing fertility treatments in the UK', the real change has been in egg donation, where the unstoppable advance of vitrification has made egg banking routine and the provision of an online donor catalogue possible, also recognised this month in The Economist. Here, couples can make their own decisions about their donor without the need for overseas travel, synchronised cycles or long waiting-lists. Having terminated in 2014 our links with overseas gamete banks, we can provide all donor oocytes needed by patients at our partner clinics in the UK. Legislation, technology, cryosecurity and best practices in the UK combine well to support recipients' decisions to seek donor treatments here.

Significantly, in 2022, 98 percent of our own egg donation cycles relied on frozen eggs from our own centres provided by UK donors with none from overseas banks. Thus, storage, shipping, distribution to other UK centres and even the revived sharing of frozen-thawed eggs are all integral to increasing patient choices at home. This was unthinkable ten years ago, when patients were heading to overseas clinics or facing impossible waiting-lists. Today, only the gametes need travel, not the patients.

Despite our upbeat record, non-medical egg freezing – performed exclusively in a private setting in Britain – has not always enjoyed commentator support. The cheerleaders, so the critics claim, lie only in the clinics, which sell an unproven service to a vulnerable population. Of course, finances matter but in a regulated environment clinics are also conscious of their professional commitment to patient welfare – and patients themselves are fully aware of what they can expect from their clinics. Fabrication or any lack of transparency to patients would be subject to sanctions from the regulator and would undermine a clinic's operational framework of care for its patients. Doubting a licensed centre's own dedication to good service is not supported by the facts.

Egg and embryo freezing are now at the heart of assisted reproduction, a textbook example of how concurrent developments in interrelated fields (cryotechnology, genetic testing, digital and data science, social marketing, shipping, logistics, time-lapse culture, for example) with their collective know-how, can create a globally acceptable and measurable practice. In our own field the impact of vitrification is matched only by that of ICSI (30 years ago) or IVF itself (45 years ago) as true transformers in the management of infertility.

As London Egg Bank marks its first decade, its own progress reflects the wider changes now seen in assisted reproduction worldwide. Eggs can be frozen or fertilised fresh for incubation and transfer, they can be donated to another patient or saved for oneself at a later date, they can be shipped and distributed worldwide. Reproductive choices today are multiple, a reflection indeed of the many family formations which in the past decade assisted reproduction has made possible.