Washington: Thousands of women and pet dogs undergo a hysterectomy and have their ovaries removed along with their uterus. Now, research looking at longevity may challenge almost decades of standard operating procedures used in women and in pets.
The team led by David J. Waters, executive director of the Gerald P. Murphy Cancer Foundation, studied more than 29,000 women who underwent a hysterectomy for benign uterine disease.
Waters` work is the first investigation to look for a link between retaining ovaries and reaching exceptional longevity in mammals.
The findings showed that the upside of ovary removal - protection against ovarian, uterine and breast cancer - was outweighed by increased mortality from other causes.
As a result, longevity was cut short in women who lost their ovaries before the age of 50 compared with those who kept their ovaries for at least 50 years.
"For the last 35 years, most doctors have been routinely advising women undergoing hysterectomy to have their ovaries removed to prevent ovarian cancer," Waters said. "We believe that such an automatic recommendation is no longer warranted."
Research shows that the same is also true of female dogs. The study, exploring the factors that favour successful aging in pet dogs, was conducted by a team also led by Waters.
They collected and analysed lifetime medical histories, ages and causes of death for 119 canine "centenarians" - exceptionally long-lived Rottweiler dogs living in the US and Canada that survived for 13 years, which is 30 percent longer than average Rottweilers.
"A female survival advantage in humans is well-documented - women outnumber men by 4:1 among those who reach 100," said Waters, also a professor in veterinary clinical sciences.
"Like women, female dogs in our study had a distinct survival advantage over males. But taking away ovaries during the first four years of life completely erased the female survival advantage."
The research was published in Aging Cell.