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Dogma Overturned: Women Can Produce New Eggs [Video]

The views expressed are those of the author and are not necessarily those of Scientific American.

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A study led by Jonathan Tilly of the Massachusetts General Hospital overturns the decades-long idea that women are born with all the eggs they will ever have. It reports that women of reproductive age carry ovarian stem cells, meaning that they can produce new eggs. Tilly’s team, which made a similar finding in mice in 2004, also discovered that mouse eggs derived from such stem cells can indeed be fertilized.

Our colleagues at Nature Medicine, which is publishing the paper today online, created this four-minute video explaining the results. (Scientific American is part of Nature Publishing Group.)



Philip Yam About the Author: Philip Yam is the managing editor of He is the author of The Pathological Protein: Mad Cow, Chronic Wasting and Other Prion Diseases. Follow on Twitter @philipyam.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. Richieo 5:56 am 02/27/2012

    That’s great, just what the earth needs, more people, more fodder for future dole queues, now we can really go to town on over populating the planet…

    Come on scientists, get your priorities right…

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  2. 2. Paleoecologist 9:17 am 02/27/2012

    Richieo, the scientists haven’t created the stem cells– they merely discovered something that was already there. In fact, these findings don’t necessarily mean that women will even have more children, but may help overturn the dogma that women must have children before a certain age. As a woman (and a scientist, and one who is very concerned about overpopulation), I think it’s important to understand our reproductive biology– this could have important implications to cancer research, for example. If you’re concerned about overpopulation, look to governments who want to restrict access to reproductive healthcare, not to scientists.

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  3. 3. N a g n o s t i c 10:12 am 02/27/2012

    Richieo, you have it all wrong, and are barking up the wrong tree too. The fact that women produce additional eggs can be used to reduce their objectification by men. Young women have always been looked upon as a ticking clock, ripe for exploitation. Now, with this new finding, we have reason to exploit women of all ages. Yippee!

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  4. 4. paganini59 8:18 pm 02/27/2012

    I don’t understand. Could someone explain it to me. Does this mean that women of reproductive age can produce eggs by themselves? Or is this some promising technology, in the future, that can produce eggs by using stem cells of women?

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  5. 5. Geopelia 10:37 pm 02/28/2012

    So now we know how Sarah managed to give birth to Isaac, past menopause.

    But most women these days come off the Pill after menopause and happily carry on making love into their seventies or eighties. No more risk, they think.

    Should they still take precautions?

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  6. 6. SandyO 9:41 am 02/29/2012

    Thank you for the explanation. A couple of statements stand out.
    1. Appalled at backlash so vitriolic. What makes increased reproductive age women so threatening? We are not here concerned with “virgin births” etc., which might very well threaten insecure men.
    2.As a scientist, I was struck by the professor’s statement that they “worked very hard to prove this was true.” Hmmm. That’s not the acceptable scientific approach as the required null hypothesis strives to prove just the opposite in order to maintain neutral intentions.
    3. Not sure to what effective use this finding could be put, except for enhancing conception among “infertile” reproducing-age women once the partnering male is proven fertile. It’s not as if it extends the potential to reproduce after reproductive age ends, is it?

    Congrats to those scientists for their discovery. Just that I think the jury’s still out on usefulness. But I’d love to know where I went wrong, if so. SandyO@PassERA.oprg

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  7. 7. JustAnotherThought 12:05 am 03/2/2012

    My first thought was the same as Geopelia’s – This reasons how women in the later stages of their lives can get pregnant.

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  8. 8. sstoessel 10:11 am 03/2/2012

    This isn’t just about giving grandmothers the option of reproducing. Even so, I’d have to say MYOB, guys,since 90-year-old men can still get their Viagra prescriptions without having to hear about how male infertility should be accepted as a natural result of the aging process.

    Most people don’t realize that a woman’s fertility can begin to drop off measurably as early as age 29. This research could eventually give couples struggling with infertility some options.

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  9. 9. VelvetGlover 11:19 am 03/4/2012

    I am in my mid 50s. I went into menopause 5 years ago. This past December, when I stopped eating bread, I began having regular monthly periods again.

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  10. 10. Carburn 8:00 pm 03/11/2012

    This would make it easier for couples to plan to reproduce later in life (if that is something they want to do). For so long, females have ended up sacrificing their younger years to reproduce, perhaps putting off education or career because they thought the clock was ticking. This has put many women at a disadvantage. Now if a couple don’t have children early, the man doesn’t necessarily have to find a younger woman.

    I suspect many some people may also be threatened by the idea that increased numbers of young women might be less inclined to give up their plans to have babies first. Especially those who think that is all women should be doing.

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