Doctors in in Copenhagen report keeping human eggs alive for weeks at a time using a new technique in which they create an "artificial ovary" from human tissue.

They hope this will help women have children after medical treatments or events that can harm female fertility.  These include cancer radio- and chemo-therapy; treatments for multiple sclerosis and the blood disorder beta thalassaemia; or patients who go through an early menopause.

“This is the first proof that we can actually support these egg cells.  It's an important step along the road," said Dr. Susanne Pors of the Rigshospitalet, Denmark's largest hospital in an interview with The Guardian.  "But it will be many years before we can put this into a woman," she added, projecting five to ten more years of research before artificial ovaries are ready for human trials.

Women who have been diagnosed with cancer can have their ovarian tissue removed and frozen, undergo chemo or radiation, and then have the tissue surgically re-implanted so they can go on to have babies naturally.

But in cases of ovarian cancer or leukemia, the cancer can invade the ovarian tissue itself.  This means that when frozen tissue is thawed and put back, there is a risk the disease will take hold again.  For them, the artificial ovaries could one day be the safer option because the technique to create artificial ovaries strips donated ovarian tissue of all of its cells, including any lurking cancer cells.

Dr. Pors and her team will present the research to the annual meeting of the European Society of Human Reproduction and Embryology in Barcelona on Monday.