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 Do women have unlimited human eggs?

Summary

28 February 2012

Doctors in America say it may become possible to create an unlimited supply of human eggs, to help fertility treatment. Researchers found that when they extracted stem cells from the ovaries of women, the cells spontaneously produced new eggs in the laboratory.

Reporter

James Gallagher

Report

A long-held theory is that women are born with all the eggs they will ever have. Researchers say they have shattered that idea by finding the stem cells which produce new eggs. 

Doctors at Massachusetts General Hospital used unique proteins on the surface of stem cells to fish them out of ovarian tissue.

The study, in Nature Medicine, showed that growing these cells in the laboratory resulted in new eggs being produced spontaneously. Legal and ethical rules limit research on human eggs, but the same techniques repeated on mice showed the eggs could be fertilised and produce embryos. 

The findings are a long way from being used in fertility clinics but the researchers said the cells had unprecedented potential to overcome infertility. British experts said the study rewrote the rule book and opened up exciting new possibilities for women.