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Using a vitamin that is already on the market, Toronto scientists suspect they have found a way to make old human eggs young again – a prospect that could turn back time on a woman's biological clock and extend her natural ability to have a healthy child.

The treatment has so far only been shown to work in animals, but word has spread so widely on the Internet that anxious women even outside Canada have begun dosing themselves with "CoQ-10," a natural antioxidant used in anti-aging skin creams and increasingly in medical research and treatments.

The quality of a woman's eggs drops sharply after age 35, increasing the risk of miscarriage and chromosomal abnormalities such as Down syndrome. Yet ever more women delay having children into their late 30s and 40s, and figuring out how to keep human eggs healthy beyond that time is one of the tallest hurdles in reproductive medicine.

By injecting "old, retired breeder" mice with CoQ-10, scientists at the University of Toronto say they were able to rejuvenate the animals' eggs – spurring more eggs to develop, and of a quality as genetically normal as the eggs of mice in their prime. The offspring of the treated older mice, the human equivalent of age 50, also looked as healthy as those with younger mothers.

Animal research rarely translates perfectly into people. But the work looks promising and safe enough that researchers have ethics approval through Mount Sinai Hospital to test the treatment for two months in 50 women over age 35.

"My feeling is that it works. … I don't think it will delay the onset of menopause, but I do think it will improve the quality of eggs," said U of T study leader Robert Casper, a senior scientist at Sinai's Samuel Lunenfeld Research Institute. "People are very excited about it."

Dr. Casper is to present the work today at the annual meeting of the Canadian Fertility and Andrology Society conference in Toronto.

Yet doctors are having a hard time convincing women to join the study – none of those eligible want to end up in the group that gets the placebo instead of the experimental treatment. "A lot of women are just going ahead and taking it themselves," Dr. Casper said. At the same time, he says patients who heard about the trial at his fertility clinic, the Toronto Centre for Advanced Reproductive Technology, have then shared the news on the Web.

"I heard from a physician in Colorado, who told me that women in his practice were all taking it … but he didn't know why until he heard a presentation I gave."

To date, the only known side effects of CoQ 10, Dr. Casper says, is that some women taking it suffer from insomnia.

Roger Pierson, a infertility expert at the University of Saskatchewan, who takes CoQ-10 daily for its heart benefits, said "it makes sense that it might help eggs overcome environmental insults."

"It's absolutely brilliant that it worked this way in animals, but the reality is there's no way to compare old mice eggs with old human eggs," Dr. Pierson said. "I will be very interested to see the data coming out."


Freezing human eggs has been one promising way to extend their lifespan. But removing a woman's eggs to freeze for later use is risky, invasive and expensive.

Searching for other ways to keep eggs young, researchers have looked to their energy source – special structures inside them called mitochondria. Like batteries, mitochondria power operations in every cell. But the egg, explains University of Toronto scientist Robert Casper, has much more of them – about 200 times more.

This, he says, is because the human egg is like that "flashlight in the closet you leave on the shelf at the cottage for years." It lies dormant until a girl hits puberty, when eggs mature monthly.

But after 35 years, the batteries wear down. At age 40, nine out of 10 eggs are abnormal, he says. But CoQ-10 is like "a fuel source" that helps keep the cellular batteries powered up – perhaps even in the human egg.

Discovered in the 1950s, Q-10 is a form of enzyme the body makes naturally. It can boost the energy output of mitochondria and help repair them. It can also be made in a lab, and demand for it has spiked as a potential treatment in neurological disorders, cancers, diseases of the heart, muscles and gums.

Carolyn Abraham

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