The European Society of Human Reproduction and Embryology is asking fertility clinics, sperm banks and egg banks to stop treating donor limits as a local paperwork problem. At its London meeting on July 8, the group backed a Europe-wide cap on how many families can use gametes from a single donor.
The immediate proposal is a ceiling of 50 families per donor, according to ESHRE’s position work presented at the meeting. Jackson Kirkman-Brown, a professor of reproductive biology at the University of Birmingham, said the group wants Europe to move toward 15 families per donor. Vasanti Jadva, who studies the psychological well-being of donor-conceived people at City St George’s in London, said even that number may prove too high because researchers still do not know the right threshold.
The policy problem is not theoretical. Sperm can be frozen, stored for years and shipped across borders. A donor who is within the rules in one country can still end up with genetic children scattered across several jurisdictions. National caps then become a spreadsheet with holes in it.
ESHRE’s position follows consultation with fertility specialists, clinics, sperm and egg banks, donors and donor-conceived people, according to the group’s document. Kirkman-Brown told the meeting that a transnational limit is the only approach that makes sense.
Why national caps are breaking down
Many countries have already restricted anonymous sperm and egg donation, including the UK. The Netherlands banned anonymous donation in 2004. Ties van der Meer, a 47-year-old conceived at a private Dutch fertility clinic using an anonymous sperm donor, says the doctor who ran the clinic later destroyed records that could have identified donors.
Van der Meer, who chairs Stichting Donorkind, an advocacy foundation for donor-conceived people, has said children have a right to know their biological parents. He eventually found one sibling, then identified his biological father and other relatives. He still does not know how many siblings he has.
Cheap consumer DNA testing has made anonymity less durable than clinic forms suggest. Services such as Ancestry and 23andMe, plus genetic registries, can connect donor-conceived people with parents and half-siblings even where donor identities were meant to stay hidden.
Some discoveries are far larger than families expect. Dutch donor Jonathan Meijer, who began donating in 2007, was linked to between 550 and 600 children, according to the BBC. Stichting Donorkind took him to court, and in 2023 a Dutch court ordered him to stop donating.
Large donor sibling groups can also create medical and social risks. Donor-conceived people may unknowingly form romantic or sexual relationships with genetic relatives. A donor carrying a harmful genetic mutation could pass it to many children, although donor screening makes that less likely in regulated systems.
That risk has still materialized. A man who donated sperm to a Danish sperm bank was found to carry a mutation associated with a significantly higher risk of several cancers. Deutsche Welle reported that his sperm had already been used to conceive at least 197 children across Europe. Some developed cancer, and some died.
The enforcement problem
Existing rules vary sharply. Data presented at ESHRE’s London meeting showed that Malta and Cyprus allow egg and sperm donors to contribute to the birth of only one child. The UK sets its limit at 10 families per donor. Denmark sets a national limit of 12 families, while also serving as a major sperm exporter.
UK fertility regulator data show that more than half of sperm donations used in the UK in 2020 were imported, mostly from Denmark or the US. That trade is why ESHRE is pressing clinics and banks, rather than only lawmakers, to respect a shared cap.
The group’s proposal may also create a supply problem. If regulated donor sperm becomes harder to obtain, some recipients may turn to unregulated donors who have not undergone health screening. The UK’s Human Fertilisation and Embryology Authority has warned that unregulated arrangements can also raise legal problems, including disputes over parental rights.
The American Society for Reproductive Medicine points to guidance saying it has been suggested that, for a population of 800,000, a single donor should be limited to no more than 25 births to reduce the risk of reproduction between relatives. Van der Meer argues for a much lower bar: five families per donor, and two families for international donations. He still called ESHRE’s proposal a positive first step.
This story draws on original reporting from MIT Technology Review.
