The age at which a woman goes through menopause is linked to her lifespan. Understanding why could unlock the secrets of aging.
Menopause, the stage at which the ovaries cease to function, is only experienced by five species in the animal kingdom. Four species, killer whales, short-finned pilot whales, belugas, and narwhals, are aquatic creatures, while the fifth is humans.
According to Jennifer Garrison, a reproductive aging researcher at the Buck Institute in San Francisco, menopause is not a biological necessity. Therefore, she believes that it should be eliminated.
The process of menopause is still not fully understood by science. One interesting difference between the male and female reproductive systems is that while the male system ages at the same rate as the rest of the body, the female system ages at a faster rate of about two and a half times faster on average, specifically in the ovaries [1].
According to Garrison, even though a woman’s body is functioning at its best in her early thirties, her ovaries show signs of aging. Surprisingly, the medical community considers this age to be “geriatric,” which is quite a term for someone in their thirties.
It’s important to note that the male and female reproductive systems have distinct differences. During puberty, males begin producing approximately one million sperm cells daily. On the other hand, female fetuses are born with roughly 6 to 7 million eggs already in their ovaries, all the eggs they will ever have.
“What that means in practice is that even though I was born in the late 1970s, the egg that I came from was made in my mother’s womb in 1956.”
Menopause not only impacts fertility but also significantly impacts women’s overall health. According to Garrison, women face a fourfold increase in the risk of cardiovascular disease after menopause. The risk of diseases like osteoporosis, cognitive decline, arthritis, and autoimmune disease also increases.
Women tend to experience accelerated reproductive aging, living longer than men on average and spending more time with poorer health. “The age at which a woman goes through menopause is linked to her overall lifespan,” Garrison says. “We have absolutely no idea what’s causing this correlation.”
By understanding the underlying causes, we can gain valuable insights into female health and the aging process of all humans.
According to Garrison, ovaries indicate aging. This means that if we unravel the factors contributing to ovarian aging, we can gain insights into the aging process of the rest of the body.
Researchers like Garrison studying reproductive aging face obstacles that are not necessarily related to the complexity of biology.
In 2018, the National Institutes of Health (NIH), the US’s largest biomedical research funding organization, only devoted 15% of its $27 billion budget to women’s health. Furthermore, less than 0.1% was dedicated to female reproductive aging. “It’s basically a rounding error,” Garrison says.
Research funding for reproductive aging is insufficient and worsened by persistent biological and medical research biases [2].
Garrison reported that it was not until 2016 that the NIH required clinical studies to include both female and male animals.
“The male body really has been biology’s baseline,” Garrison says. “That means that we have basically a century of preclinical data which was conducted and collected only in males.”
This already has serious consequences.
According to data from the FDA Office of Women’s Health, 80 percent of drugs taken off the US market over safety concerns were pulled due to adverse effects in women.
A couple of years ago, Garrison established the Global Consortium for Reproductive Longevity and Equality to aid scientific research on reproductive aging.
This initiative aims to rectify the issue. “Our goal really is just to facilitate and accelerate taking those discoveries that happened in the lab and moving them into women’s hands faster,” Garrison says. “That means funding the science.”
[1]https://www.wired.com/story/aging-menopause-longevity/
[2]https://www.nature.com/immersive/d41586-023-01475-2/index.html
