Men with low sperm counts are more likely to be with increased risk of illness, BBC reports.
Those men were 20% more likely to have more body fat, higher blood pressure and more "bad" cholesterol. They were also much more likely to have low testosterone levels, a study in Italy shows.
Scientists analysed men in infertile couples in Italy, to see whether semen quality is also a marker for men's general health.
They found more of the men with low sperm counts had metabolic syndrome - a group of risk factors including a higher body mass index (BMI) and raised blood pressure. These increase the risk of developing diabetes, heart disease and stroke.
The men were also 12 times more likely to have low testosterone levels, which reduce muscle mass and bone density and can be a precursor to osteoporosis.
Infertile men are likely to have important co-existing health problems or risk factors that can impair quality of life and shorten their lives. Fertility evaluation gives men the unique opportunity for health assessment and disease prevention”, comments Dr Alberto Ferlin, professor of endocrinology at the University of Bresci, who led the study.
The study's authors stressed that their research did not prove that low sperm counts cause metabolic problems, but rather that the two are linked. They said low testosterone levels in particular were associated with these health issues.
Dr Ferlin said the research showed that it was important that men being treated for infertility were given proper health checks.