What You Need to Know About Donor Siblings

Source: prostoole / Magnific

The news is full of stories about donor-conceived children unknowingly dating in high school or feeling overwhelmed about the number of donor siblings they have. Some banks and agencies have made efforts to limit donations by each donor and educate donors about the long-term implications of donating to many families, which may incentivize donors to limit their donations. Some have even established communication systems with other banks to limit their donors’ donations.

However, stories like the one reported on CNN about the woman who inadvertently dated her “half-brother” in high school or the story about donor Jonathan Jacob Meijer, in the Netflix film The Man With 1000 Kids, have drawn a great deal of attention. It makes sense to feel paralyzed by these stories. But as I describe in my Zoom Out theory, this is precisely the moment to pause, review the facts, and focus on what you can do for your future family.

The questions for many recipients of egg or sperm donation are: Will it hurt my child to have many donor siblings, and is it possible to track donors?

The stress that many recipients carry can be heavy. Some even wonder if they should relinquish their long-held dream of having a child. They fear ruining their child’s life by bringing a child into the world with the potential for so many siblings. While it is true that there are people who have found it stressful, to varying degrees, to have many donor siblings, the research shows that donor-conceived children are thriving. It is important to note that early disclosure appears to be key in the development of a stable identity and solid relationship with the parents.

It is true that because donating sperm is much easier than donating eggs, children conceived with the assistance of egg donation may have fewer donor siblings. That said, it is still possible to have more than you may expect. Let’s consider the ways this can happen. Donors can donate to egg donation programs, egg banks, and clinics. They may also donate to friends or family members. A young donor may create many eggs, which may be more than a couple needs to complete their family. Therefore, there are possibly several children in each family, as well as many excess embryos frozen in storage.

It can be very difficult for parents to decide what to do with excess embryos, so sometimes, they are stored and used after decades. It has been estimated that there are over a million embryos stored, which can be used at any time. In fact, in the past year, we have seen healthy births from embryos that were two and three decades old. This means that with donated eggs or sperm, your child may have multiple siblings from each donation, resulting in donor siblings close in age to your child and other donor siblings the same age as your grandchildren.

The subject of The Man with 1000 Kids lived in Denmark, a country that is small and attempts to limit the number of times each donor can donate. Even with these guidelines, this donor was able to donate to many clinics around the world and to many people individually. The U.S. is a much larger country with fewer guidelines and no country-wide legal regulations. Although charges were brought against Mr. Meijer, the country of Denmark was not able to control him.

Could we invent donor tracking software or fingerprint donors? Should we follow up with parents to document how many children they have created with donor gametes, or limit how long parents can keep their embryos frozen? Many ideas have been suggested, and the State of Colorado has enacted a law that attempts to address many of the issues that recipients are concerned about when using donor conception, including donor limits. As of January 1, 2025, Colorado has limited the donations in their state to 25 per donor. This law was a large step in the world of donor conception, but it is only one state and cannot account for some of the issues addressed here, such as donating privately or using excess embryos. So, the question becomes, what can we do?

Counseling donors may help. When I assisted in the creation of the first open donor program on the East Coast, I learned how helpful it was for many donors to be educated about the implications of their donation and even connect with their recipients. I found that the more the donor understood that they would likely be asked to respond to children created with their gametes, update families with medical information, and understand the meaning their donation had for these families, the more they seemed inclined to donate to fewer families. More donors are being educated, and more attention has been brought into the zeitgeist about this issue, yet even thoughtful counseling is not a guarantee that your donor will not donate to more people than you expect.

The best thing you can do for your child is talk to them early and often about their origins and, over time, help them understand that having many donor-related siblings is a possibility. They may be in the same math class or sports team as a donor-conceived sibling. So, if your child is interested in dating someone who was also created with the assistance of donor conception, or whose parent was a donor, it may make sense to use a commercial DNA test to ensure they are not siblings. This may bother some children and not others, just like we see that some children love having many donor siblings and others do not. It is impossible to know how your child will react. Research shows that early disclosure is connected to a more stable identity and a stronger relationship with you. Some children will find this information completely unremarkable, some will feel good about it, and others may have more to process. Either way, the foundation of openness you build will be one of the greatest gifts you will give them.