American sperm banks are responsible for creating dozens of half-siblings who do not know each other, according to Le Devoir, a Canadian newspaper. The scale of the problem has only come to light because of an energetic American woman, Wendy Kramer, and her desire to know whether her sperm-donor son had half-brothers or sisters. In 2003 she set up a website, the Donor Sibling Register . This gathers information about sperm donors (identifiable only by codes assigned by the sperm bank) and enables mothers to see if their children have siblings. The site allows sperm donors to get in touch with their children, but few take advantage of that. There are currently 24,000 people registered, only 925 of them sperm donors.

To Ms Kramer's surprise, donors -- or rather, the IVF clinics -- frequently create 30, 40 or even 50 children. The record so far is an American from Virginia with curly blond hair, blue eyes and a medium complexion who has fathered 120 children. But of course more could show up as other mothers register with the website. One 31-year-old man, Ben, has discovered that he has 60 offspring, all aged about 6½. "I did it partly because I had two cousins who had great difficulty conceiving and ended up adopting. Also, in large part, I won't lie to you, because the financial aspect was very appealing," he told Le Devoir. Apparently, men receive about US$50 for each donation.

Ms Kramer has little respect for the clinics. "It is very disturbing for a parent who comes to the site and discovers that their child has 20, 50 or 70 half-brothers and sisters." She once voiced her concerns to a sperm bank manager, who dismissed them: "Since these children don¹t live in the same area, what's the problem?""That shows you the enormous gulf which separates the fertility industry from the families it creates," she says. "This man is unwilling to recognize the psychosocial ramifications of knowing your biological father has 50 children."

She also claims that clinics are economical with the truth about sperm donation. "The clinics tell them they will have no more than 10 children. They lie! They also don't take into consideration the risks of undetected genetic diseases that come that come with one man reproducing on such a large scale. It's all a question of money." ~ Le Devoir, Apr 20 (thanks to Diane Allen, of the Infertility Network for her translation)