Prolonged fertility in women linked to a longer life span, research reveals
During menopause, a woman’s ovaries stop functioning. With this cessation, the production of a cocktail of hormones responsible for general health also stops. New research looks into how the health of ovaries are connected to the life span of women, and new ways of potentially extending that life span by prolonging the vitality of ovaries.
According to Jennifer Garrison, an assistant professor at Buck Institute for Research on Aging in California, ovaries age faster (more than twice as fast) than any other body tissue in a woman’s body.
Reports from the American College of Obstetricians and Gynecologists show that an infant female has 1 million to 2 million eggs in her ovaries. At puberty, the numbers drop to 400,000 and by age 30 only 12% of the original number is available. This number tapers off to 3% at age 40.
“Ovaries are very strange, very odd in terms of the rest of the human body. We can think about them like an accelerated model for human aging,” said Garrison yesterday during a presentation at a health and wellness event called “Life Itself”.
In fact, by the time a woman reaches her late 20s and early 30s, when her body is at its optimal performance, her ovaries are already displaying signs of aging. Although this accelerated aging does not pose an immediate threat until menopause.
“When the ovaries stop working due to menopause, they stop making a cocktail of hormones important for general health. Even in healthy women, it dramatically increases the risk of stroke, heart disease, cognitive decline, insomnia, osteoporosis, weight gain, arthritis, those are medically established facts,” she added.
For this reason, the age at which a woman hits menopause is tied to how long she might enjoy her life or get to live at all. Below the age of 40, the woman is more likely to have a short life span than the one who hits menopause beyond age 50.
While prolonging fertility could enable women to have children much later in their lives, this is not the aim of the research.
According to Kara Goldman, a professor of obstetrics and gynecology at Feinberg School of Medicine, the aim of this research is to decrease and possibly eradicate the effects of menopause not to increase chances of old age pregnancies.
“That would be a completely irresponsible goal and ultimately a shortsighted one. We’re thinking about the bigger picture: The best way to prevent the health impact of menopause is to prolong the ovaries’ natural functioning,” Goldman said.
At the Global Consortium for Reproductive Longevity and Equality, launched by Garrison, the objective of the research is to understand why accelerated aging in ovaries occurs in the first place.
“Why do humans develop senile ovaries by age 30? Science doesn’t know. Learning about how little we know about why that happens infuriated me actually,” Garrison said.
The mystery of accelerated aging is also found in only four other mammals: the killer whales (orcas), the short-finned pilot whales, beluga whales and narwhals.
“What’s the fundamental cause of this decline in egg quality and quantity with age? We don’t know the answer to that. The age of natural menopause is really variable at the individual level, and we don’t know why,” she added.
In fact, the fact that male siblings of women who enter menopause later in life also tend to have an increased life span intrigues scientist about the genetic impact of menopause on family members life spans.
“Why does a woman’s reproductive span correlate with her overall life span? Even brothers of women who go through menopause later tend to live longer. There’s a genetic component there that’s clearly very important, and we don’t understand it at all,” she concluded.
Through understanding the cause behind menopause and figuring out proper interventions, the centre is looking to extend life to over 10 years.
