Research just published by two Stanford doctors answers one of the fundamental mysteries about women’s fertility: what makes egg cells develop in an ovary?
Women are born with thousands of eggs. Over our lifetimes, only a tiny percentage grow to be mature eggs, the kind that can be fertilized to make a baby. The rest never develop. When we hit menopause, thousands of eggs remain undeveloped; our bodies just stop the hormonal cycle that causes them to mature and be released.
Now, scientists have found a way to stimulate the growth of egg cells into mature eggs. The findings are early, far from being ready for clinical use with patients. But they open up a whole new avenue of hope for women struggling with infertility.
In experiments with mice, the researchers were able to stimulate these failed eggs, called “primordial egg cells”, to grow, be fertilized, and produce healthy, fertile baby mice. They also stimulated human cells to produce eggs, but did not fertilize them.
They plan to begin human trials of the technique with women whose ovaries failed early in life.
This treatment, if successful, could open up avenues to fertility with women who have suffered early ovarian failure, or want to have a child as they’re heading into menopause. Women undergoing cancer treatment would also have the option to set aside immature eggs for later fertilization.