Developing eggs from earliest stages to maturity could open the door to new approach to fertility preservation
Women at risk of premature fertility loss might have cause for new hope as researchers reveal that human eggs can be developed in the lab from their earliest stages to maturity.
While the feat has previously been achieved for mouse eggs, and has given rise to live young after fertilisation, the process has proved tricky in humans.
Experts say the latest development could not only aid the understanding of how human eggs develop, but open the door to a new approach to fertility preservation for women at risk of premature fertility loss – such as those undergoing chemotherapy or radiotherapy.
The research could be particularly relevant for girls who have not gone through puberty. Currently, to preserve their fertility ovarian tissue is taken before treatment and frozen for later implantation.
“[For young girls] that is the only option they have to preserve their fertility,” said Prof Evelyn Telfer, co-author of the research from the University of Edinburgh.
But the approach has drawbacks. In the case of re-implanted tissue, “the big worry, and the big risk, is can you put cancer cells back,” said Stuart Lavery, a consultant gynaecologist at Hammersmith Hospital, who was not involved in the study.
The new research offers a way for eggs to be extracted, grown and used, without the need to re-implant the tissue. “When you have got the eggs, of course you would have no contaminating cells – hopefully it would be an embryo that you would be implanting back in,” said Telfer.
But, she warned, it would be several years before the technique could be used in clinics, with further tests needed to make sure the mature eggs are normal and the process safe.
Writing in the journal Molecular Human Reproduction, researchers from Edinburgh and New York describe how they took ovarian tissue from 10 women in their late twenties and thirties and, over four steps involving different cocktails of nutrients, encouraged the eggs to develop from their earliest form to maturity. Of the 48 eggs that reached the penultimate step of the process, nine reached full maturity.
SOURCE: The Guardian – Nicola Davis