Hope for infertile women as scientists create eggs from stem cells in mice before using IVF to produce healthy young
06:51 GMT, 5 October 2012
For the first time, scientists have not only succeeded in making eggs, but using them in IVF to produce healthy young.
Experts describe the work as incredible and point out that the baby mice born as a result of the experiment went on to have pups of their own.
The breakthrough, from researchers who have already made sperm in a test-tube, could eventually allow women left infertile by treatment for cancer or by premature menopause ‘grow’ new eggs.
Incredible: Scientists have succeeded in creating eggs from stem cells which then went on to product their own young. Pictured are some of the offspring from the eggs created in the lab
It could also shed new light on female infertility and allow women to become pregnant with babies that are genetically their own late in life.
Dr Allan Pacey, a Sheffield University fertility expert, said the Japanese work was ‘remarkable’ research that could one day lead to the ‘routine’ production of new eggs.
However, he cautioned that the work is still an early stage.
Others questioned the need to go to such great lengths to satisfy the urge to have family and pointed out that advances in both sperm and eggs raise the possibility of couples having babies through entirely artificial means.
The research team, from Kyoto University, started with stem cells, ‘blank’ cells capable of turning into other cell types and used a cocktail of nutrients to turn them into very early-stage eggs.
These were then grown in the lab with ovary cells before being transplanted into a mouse’s ovaries to mature.
Healthy: The mice born from the eggs created have, in some cases, gone on to have their own offspring
The next step in the complicated process involved removing the eggs and using IVF techniques to fertilise them.
Eight pups were born via two different techniques, the prestigious journal Science reports.
One recently died but the others were all healthy and some have gone on to have litters of their own.
In future, it might be possible to replicate the process, using just a sliver of a woman’s skin as the stem cell source.
Although some progress has been made before, this is the first time scientists have succeeded in making fully-functional eggs.
Researcher Katsuhiko Hayashi said that those who could benefit in the future include young cancer patients and post-menopausal women.
The work could also lead to new fertility drugs.
However, the big differences between mice and people and the need for extensive safety testing mean that test-tube eggs are still at least a decade away from use in fertility clinics.
A change in the law would be need for them to be used in treatment in the UK.
Dr Bryce Vissel, an Australian stem cell expert, described the work as incredible.
But he added that any human work will be ‘fraught with scientific challenges and hurdles, including major questions relating to viability, reliability and safety’.
Josephine Quintavalle, of campaign group Comment on Reproductive Ethics, warned that any health problems could afflict generations to come.
She added: ‘The issue is always the more you meddle around the more things can go wrong.’
Geeta Nargund, head of reproductive medicine at St George’s Hospital in London, said that women facing fertility problems need to take action now, rather than wait for this research to bear fruit.
She said that those at risk of premature menopause can freeze their eggs, while those whose eggs have dwindled should consider IVF.