Professor Ian Craft of the London Fertility Centre predicts a serious shortage of donated sperm and eggs in the wake of new legislation that gives donorcreated children the right to know their biological parent on reachingthe age of 18. "A significant part of our practice concerns men with subfertile sperm counts, and I feel particularly sorry for those people because the loss of donor anonymity means they face double the problem," said Professor Craft. "The number of sperm donors has already dropped significantly."