Babies created from the tissue of an "unborn mother" came a step closer yesterday after scientists said they had made progress in producing eggs from an aborted foetus.
The development, which raises the prospect of children with unborn biological mothers, has met with widespread criticism from fertility researchers and pro-life campaigners.
Speaking at a meeting of the European Society for Human Reproduction and Embryology in Madrid, Tal Biron-Shental, of the Meir hospital, in Kfar Saba, Israel, said the controversial technique could be used to provide eggs for fertility treatment.
The announcement is likely to spark widespread debate and concern over how far scientists are prepared to push the both medical and ethical frontiers.
Fertility experts argue that the developments could ease a worldwide shortage of donated eggs for women who are unable to produce their own. But anti-abortion groups have branded the process "sickening" and have warned of the emotional and psychological problems that children born this way could face.
Dr Biron-Shental's team had taken slices from the ovaries of seven foetuses aborted be tween 22 and 33 weeks. A hormone was added to stimulate the growth of follicles, the tiny sacs inside the ovarian tissue which encase cells that eventually grow into eggs.
All but one of the foetuses had been aborted due to malformations. The researchers found that the ovarian tissue survived for a month, and that the primordial follicles inside it began to mature into primary and secondary follicles - about halfway along the developmental path to fully mature follicles that can produce fertile eggs.
Dr Biron-Shental said it was "the furthest stage anyone has got" in maturing eggs from embryos in the laboratory.
Eventually, she said, her team hoped that eggs grown in this way could be used by couples who could not have children naturally: "There is a shortage of donated eggs for IVF. The goal is still theoretical, but if we can mature those eggs we could use them for donation for IVF."
She admitted that the work raised huge ethical issues. "We don't have all the answers for those," she said.
Francoise Shenfield, a specialist in medical ethics at University College London, said: "You could say, if you're creating a new life, it might be a good thing because a new life is better than no life." But she added: "We don't work in a vacuum. Society is not ready for this."
However, Dr Biron-Shental said: "We use sperm that's donated. Ethically, it's almost the same. There's just the question of whether your mother was an aborted foetus or your father was someone who donated his sperm.
Roger Gosden, a fertility expert at the Jones Institute for Reproductive Medicine in Norfolk, Virginia, said it would be less controversial to take ovarian tissue from a woman, for which consent could be given. There may also be dangers in using eggs from foetuses, he added. Although women are born with around seven million eggs, by the time they reach puberty, this number has dropped to about a quarter of a million. The reason for the loss of eggs is unknown, but some researchers believe it may be because they develop defects. It would be impossible to know if the egg grown from the embryo might be one that would otherwise have been destroyed by the body.
The human fertilisation and embryology authority, which regulates fertilisation procedures in Britain, said such a procedure for producing eggs for IVF would not be allowed in Britain.
"It would be hard for any child to come to terms with be ing created using aborted foetal material," an HFEA spokeswoman said.
"The authority does not consider the use of tissue from this source to be acceptable for infertility treatment."
The HFEA licences procedures involving embryos, but is coming under increasing pressure to rethink its bar on creation of life to save life except where inherited diseases are involved.
Last month, Suzi Leather, the HFEA chairman, acknowledged that rules made over a decade ago may be past their sell-by date.
Her acknowledgement came on the back of the birth of Britain's first "designer baby" Jamie Whitaker who was born in the hope of allowing his sick older brother Charlie to receive treatment for a blood disorder, Diamond Blackfan anaemia.
Nuala Scarisbrick of the charity, Life, said: "This is sickening and disgusting. Adults who give donor eggs presumably know what they are doing, but a dead baby who is aborted obviously cannot give consent.
"Children manufactured as a result of these donor eggs will probably often be the result of donor sperm.
"This means they will have no sense of their own identity and may have enormous psychological problems."
