But Professor Eliezer Shalev, of Technion Israel Institute of Technology in Haifa, northern Israel, who led the research, said that doctors have been looking for an alternative to egg donation for a long time and they hope it will soon be possible to grow as many eggs as needed.Amniotic cells develop at the early stages of the life of the foetus and are known to be able to change into other cell types.So far eggs grown from amniotic sac cells are immature, at the stage of germ cells found in the ovaries of girls before they reach puberty.Scientists have now started using hormone stimulating chemicals to develop these cells into mature eggs capable of fertilisation by sperm.Prof Shalev, whose work was published in the journal Reproductive Biology and Endocrinology, believes it may be possible to grow mature eggs in two to three years.However, Prof Lawrence Shaw, a leading London fertility specialist, said: "There might be ethical issues."There could be an argument that the amniotic membranes belong to the baby they surrounded. This would have to be tested in court," he noted.Source: ANI