Men with low sperm counts are at higher risks of potentially deadly illnesses like heart disease and diabetes, new research suggests.
A new study of more than 5,000 men found that the odds of high blood pressure, cholesterol and more body fat were 20 percent higher for those with low sperm counts.
One in 20 men is thought to struggle with some form of infertility issue, typically measured by sperm count and quality.
Researchers from the University of Padova in Italy said that their findings mean doctors and the men they treat for infertility should see sperm count as a symptom that could act as an early indicator of other illnesses later in life.
Men who struggle with infertility are 20 percent more likely to show early warning signs of illnesses like heart disease and diabetes than are other men, new research shows
About one in every 10 couples struggles to conceive a child to fertility issues in one or both parents.
What’s more, global sperm counts and qualities have been plummeting in recent years, a pattern that many scientists have warned may itself be a warning sign of bigger problems for the future of the human race.
The causes of low sperm counts – considered to be anything under 15 million sperm per milliliter of semen – are complex and include both genetic and lifestyle factors.
Men may have hormonal or autoimmune abnormalities that hamper sperm production or destroy sperm, but factors like stress, drinking and obesity can also interfere with fertility.
Previous studies have linked infertility with other health problems and even earlier deaths, but these have primarily documented the connection in small groups of patients.
The new study, presented Sunday at the Endocrine Society annual meeting, established the phenomenon clearly among a large sample of Western men.
Among the 5,000 men whose medical data was analyzed, the researchers found that those who had struggled to conceive children with their partners were 20 percent more likely to have high levels of bad cholesterol and lower levels of good cholesterol.
Taken together, this collection of symptoms is referred to as metabolic syndrome, and it raises men’s risks for heart disease, stroke and diabetes, but may be alleviated by lifestyle changes like improved diets, more exercise and avoiding bad habits such as smoking.
These men were also more likely to be overweight or obese and have low levels of testosterone, a condition called hypogonadism.
‘We did not expect the high prevalence of hypogonadism,’ said lead study author Dr Alberto Ferlin, a professor of internal medicine and andrology at the University of Padova.
‘We know form clinical practice that infertile men could have low testosterone, but we didn’t expect that the prevalence would be so high,’ he said.
The infertile men whose data was analyzed for the study were at a 12-fold greater risk for hypogonadism than more fertile ones were, and half of those men also had low bone density.
In men, testosterone can be converted to estrogen, which is a key hormone to the production of new bone material, keeping the skeleton dense and strong.
Scientists don’t quite know how testosterone and cholesterol interplay. This study is not the first time that worse cholesterol levels have been seen in men with low testosterone, but attempts to right the imbalance of good and bad cholesterol with hormone therapy have yielded mixed results.
Dr Ferlin said that his study demonstrates that ‘infertile men should not be looked at only with a focus on having a child but…from a physician’s point of view, you have to consider that [infertility] is a mirror or marker for other illnesses.’
Most of the men included in the study were relatively, with ages hovering around the 30s, according to Dr Ferlin.
All of the related risks are symptoms that worsen with age, and probably had not yet begun to cause any other serious health complications for the infertile men.
‘This is important because these patients are younger [when they] are looking for a child, they’re not 80 years old, so if a doctor finds some metabolic issue or osteoporosis, they have the opportunity to treat or even prevent other important consequences later in life,’ said Dr Ferlin.