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Ancestry DNA Tests and the Implications on Sperm Donation and Anonymity

At-home DNA kits have become hugely popular over the past few years. For many, they’re a fun way to explore family trees or trace genetic heritage. But for those who have used, or contributed to, donor sperm, these tests raise important questions about privacy, identity and connection.

From sperm donor anonymity to the growing impact of ancestry tests, here’s what you need to know—whether you’re considering donation, starting treatment, or simply curious.

How DNA tests are changing donor anonymity

As of the 2005 HFEA law change, sperm donors are anonymous at the point of donation and treatment. When someone chooses to use donor sperm, they receive only non-identifying information—like the donor’s height, hair colour, occupation, and medical history.

Later on, donor conceived people are able to access identifiable information about their donor once they reach the age of 18. This information includes a donor’s name, last known address, and any other information provided to the clinic. This information, however, is only accessible if a donor conceived person is aware that they are in fact donor conceived. If this information has been withheld from their family, they will not know that this resource is available to them.

But these vital and well-respected laws about sperm donor anonymity are potentially compromised by at-home ancestry DNA tests.

Can you find your sperm donor on ancestry DNA?

Increasingly, people are discovering their genetic background through ancestry DNA sites—sometimes by accident. A person might take a test out of curiosity and find unexpected genetic matches. Or they might discover they were donor conceived through connections made on DNA databases.

This means that even if a donor-conceived person hasn’t applied for identifying details through official channels, they could still connect with a donor—or with half-siblings—via ancestry sites. Similarly, donors who take a DNA test might unintentionally connect with their genetic offspring.

Over the recent years, there have been multiple instances of a person coming to learn that they were donor conceived without previously knowing that their parents were not genetically related to them; or donors and donor conceived people attempting to find their genetic relatives, before the anonymity is lifted.

This was a topic explored in a BBC Two series DNA Family Secrets, where in one episode a sperm donor discusses their experiences donating prior to the 2005 HFEA regulation, where donations were completely anonymous, and their journey to try and find people conceived from their donations through ancestry DNA test sites.

Donor sperm and ancestry tests: What HFEA says

The Human Fertilisation and Embryology Authority (HFEA) recognises that ancestry DNA kits have changed the landscape of donor anonymity. That’s why every sperm donor is now fully informed about the possibility of future contact via DNA matching—even if they donated under the assumption of anonymity.

“These kits can match offspring and donors and reveal that they are related, should both have taken the test,” says Sameer, Senior Andrologist and Donor Coordinator at London Sperm Bank. “This can be quite distressing for recipients and donor-conceived people if the offspring did not know they were donor conceived. It can also be distressing for donors who become identified before they expect to be.”

For donors and families, it’s a reminder that genetic connection can surface in unexpected ways. However, this knowledge doesn’t necessarily deter people from using the testing services.

The HFEA references a survey carried out in 2020 from We Are Donor Conceived, which found that 78% of respondents stated that they had successfully identified their donor through at-home ancestry DNA tests. Whilst this may not be a representation of all donor conceived people as a whole, it indicates that there is a potential for those who are donor conceived or donors themselves to find each other and make connections.

Talking openly about donor conception

While sperm donor DNA testing can lead to emotional or complex discoveries, it also opens up opportunities for more open conversations.

Jamie Forster, Senior Fertility Counsellor at London Sperm Bank and London Women’s Clinic, explains:
“The truth is we can’t promise absolute anonymity anymore. Recreational DNA testing and ancestry kits have changed that. That’s why it’s so important we learn to talk openly about donor conception.”

“For recipient families, that means being transparent with children from an early age about their donor origins. And for donors, it means involving partners, families or children in the decision to donate—so there are no surprises later.”

What London Sperm Bank is doing to support donors and families

At London Sperm Bank, we don’t discourage donors or recipients from using ancestry DNA kits. But we do ensure everyone is aware of the implications.

Our team supports donors through expert counselling and guidance before they donate—so they’re informed about the potential for future DNA matches. We also support recipient families in navigating these conversations with confidence, compassion and care.

We believe informed choice is key. Whether you’re thinking about donating sperm or starting a family using donor sperm, you deserve full transparency about what sperm donor DNA testing could mean in the future.

What to consider before taking an ancestry test

If you’re a donor or part of a donor-conceived family, here are a few things to think about before you take—or gift—a DNA test:

• Consider the potential for unexpected matches. You or your child may be connected with genetic relatives through DNA matching algorithms.
• Be ready for emotional impact. Even happy discoveries can bring up complex feelings—especially if donor conception hasn’t been openly discussed.
• Talk to your family first. Open, honest conversations about donor conception can help prevent confusion or distress down the line.

Final thoughts

At-home DNA testing has made it easier than ever to uncover genetic connections. For sperm donors and donor-conceived people, that can be empowering—but it also means that anonymity is no longer guaranteed.

By staying informed and supported, you can approach these developments with clarity and confidence. And if you’re ever unsure, our team is here to help.

Find out more about the benefits of sperm donation as well as how to apply today.