TODMORDEN, England (Reuters) - Women having fertility treatment should be given the option to donate for research any extra eggs they do not use, the head of the first European team to clone a human embryo believes. Dr Miodrag Stojkovic, of Newcastle University in northern England, told Reuters one of the greatest obstacles to stem cell research -- which could lead to cures for conditions such as diabetes, cancer and Parkinson's -- was obtaining fresh eggs. "What we are using are eggs which are usually discarded. The development potential is not the same as fresh eggs," said Stojkovic, a stem...