Denmark's European Sperm Bank, which sold the sperm, said families affected had their "deepest sympathy" and admitted the sperm was used to make too many babies in some countries. There is no law on how many times a donor's sperm can be used worldwide. In Belgium, a single sperm donor is only supposed to be used by six families. "It is generally safer to have a child with the help of donor sperm if the sperm donors are screened according to medical guidelines." What if you are considering using a sperm donor?