Researchers in Belgium have taken the first steps towards producing a transplantable artificial ovary after demonstrating successful follicle survival in mice.
The new technique could in the future offer cancer patients who have had their fertility affected by chemotherapy, and who have not stored their eggs, an alternative to ovarian tissue freezing, which presents a risk of reintroducing cancerous cells when the tissue is reimplanted.
To develop the synthetic ovary, researchers at the Catholic University of Louvain isolated egg-producing follicles from frozen human ovarian tissue and encapsulated them in a protective casing made out of fibrin – a tough scaffolding protein that is normally found in blood clots.
The synthetic ovaries were then transplanted into the abdominal cavities of mice. After a week, the researchers found that about 20 percent of the follicles were still alive and appeared to be growing healthily. This survival rate is similar to that seen after transplantation of frozen ovarian tissue (a technique that has resulted in more than 60 live births), suggesting that the artificial ovary technique could hold promise.
Lead author of the study, Dr Christiani Amorim, told New Scientist that their results 'look very encouraging'. However, it is not yet known if the follicles in artificial ovaries are capable of being fertilised and leading to live births.
So far the study has only taken place in mice, and the technique will need to be developed further before it could be applied to humans. The researchers will need to test whether the artificial ovaries can survive for longer periods of time after transplantation. More work is also needed to find the optimal chemical composition and rigidity for the protective fibrin case.
'The progress of this work is fascinating, but it is still an open question whether it will be successful,' said Professor Michael von Wolff of the Women's University Hospital in Bern, Switzerland, who was not involved in the study. 'We don't know if an artificial ovary would be as effective as ovary freezing,' he added.
As well as helping female cancer patients, the technique could also benefit women with endometriosis or who have undergone premature menopause.
Professor Claus Andersen, a reproductive physiologist at the University Hospital of Copenhagen, Denmark, told New Scientist: 'When fully developed this technology may be used in women who want to delay having babies for social reasons, or who want to postpone the menopause.'
The results were published in the journal Reproductive Biomedicine Online.