Dutch Mass Sperm Donor Fathered 199 Children, 11 in Belgium
A 43-year-old Dutch man known as “mass donor Simon” has admitted to fathering at least 199 children through sperm donations across multiple European countries, including 11 in Belgium. The revelation, detailed in a letter sent to donor parents and obtained by NOS/Nieuwsuur, has reignited concerns about the lack of effective limits on sperm donation across European borders.
According to VRT NWS, Simon’s children are spread across the Netherlands (172), Belgium (11), Germany (15), and one other European country. One woman is reportedly still pregnant. The number is significantly higher than the 121 children initially reported by the investigative program Nieuwsuur earlier this week.
A Donor Operating Outside Clinical Oversight
Simon, from the Groningen region, used multiple aliases including Jesse, Johan, Daan, Sam, and Maarten. While he donated to several sperm banks, he primarily operated outside clinical settings, contacting prospective parents through websites and arranging home inseminations. This informal approach placed him beyond the reach of standard regulatory oversight.
In his letter, sent via a group chat with over 35 parents, Simon acknowledged the scale of his donations. “I believed I was doing the right thing and helping people: the appreciation and seeing the intense happiness were my only motivation,” he wrote. “Now I know I have seriously failed you.” He added that he has stopped donating and is seeking professional help.
Government Knew for Years, Took No Action
Perhaps most troubling is the revelation that the Dutch Ministry of Health (VWS) has known about Simon’s activities since August 2017 but took no action. In 2019, he was even placed on a government committee evaluating the donor law, as NOS/Nieuwsuur reported.
Dutch Health Minister Sophie Hermans expressed deep regret over Simon’s committee appointment. “Nevertheless, this gentleman should of course never have been allowed to sit on the advisory committee,” she said. “That it did happen, I deeply regret.”
In the Netherlands, a sperm donor may legally donate to a maximum of 12 families since 2025, when the new donor law took effect. Before that, fertility clinics operated under a guideline maximum of 25 children. However, donors operating outside clinical settings are not bound by these limits.
Belgian Investigation Launched
In Belgium, where the legal limit is six families per donor, the Federal Agency for Medicines and Health Products (FAGG) has launched an investigation into whether Simon donated at Belgian fertility clinics or through informal channels. FAGG spokesperson Ann Eeckhout said the agency is now requesting formal information through Dutch authorities. “Based on those media reports, it appears there is fraud involved,” she told VRT NWS.
Ties van der Meer, chair of Stichting Donorkind (Donor Child Foundation), was blunt about the situation: “This man must be stopped.” The foundation is considering legal action similar to the case against Jonathan Meijer, another Dutch mass donor with over 500 children who was banned by a Dutch court in 2023 from donating further sperm.
Part of a Broader Scandal
Simon’s case is the latest chapter in a wider European donor scandal. In Belgium, the crisis has been unfolding since May 2025, when a Danish donor was found to have fathered at least 53 children in the country despite carrying a cancer-causing genetic mutation. Since then, VRT NWS has reported that at least 93 sperm donors in Belgium have been used more often than legally allowed, with at least 29 of those donors carrying genetic abnormalities. Belgian fertility centers themselves have also come under scrutiny for exceeding donor limits.
The Belgian federal government abolished donor anonymity for egg and sperm donors in February 2026, and the donor registry is being expanded with pre-2024 data, expected to be completed by July 2027.
Regulatory Gaps Exposed
The Simon case highlights critical weaknesses in the current system. Cross-border donation allowed Simon to exploit differences in national regulations across at least four European countries. Informal donation channels arranged through websites and home insemination fall entirely outside clinical oversight. And crucially, the Dutch Public Prosecution Service has stated that under the donor law, only fertility clinics or healthcare professionals can be held criminally liable for violations - not donors themselves.
Mothers affected by Simon’s donations describe a sense of profound disruption. Babs, a mother from Groningen province who had a daughter through Simon in 2012, told RTV Noord: “It’s simply incomprehensible. Your brain can’t handle seeing so many brothers and sisters side by side. Suddenly you’re confronted with a situation nobody asked for. It feels disruptive.”
What’s Next
As more mothers come forward and the true number of Simon’s children continues to rise, pressure is mounting on both Dutch and Belgian authorities to close the regulatory gaps that allowed this situation to develop. The FAGG investigation will determine whether Simon was active in Belgian clinics, while Stichting Donorkind explores legal avenues to prevent him from donating further.
The case serves as a stark reminder that in an era of cross-border healthcare and informal online arrangements, national regulations alone may be insufficient to protect prospective parents and donor children from the consequences of unchecked mass donation.