A man who carried a rare genetic mutation associated with an increased risk of cancer has fathered at least 67 children through sperm donation across Europe. According to reports, ten of these children have been diagnosed with cancer. This case has brought attention to the lack of internationally standardized regulations regarding the screening of sperm donors for genetic mutations that may increase health risks for offspring. Currently, regulations on donor screening and the maximum number of children that can be conceived from a single donor vary significantly between countries. Medical experts and advocacy groups are calling for more stringent and harmonized rules to prevent similar cases in the future and to better protect the health of donor-conceived children.