Men with two or more impaired semen parameters may face a higher risk of death and relatedly a shorter life span, according to new research, which would suggest a common etiology between infertility and mortality.

The seven-year study involved 11,935 males, averaging the age of 36, in Texas and California who had undergone infertility evaluations.

According to the results low semen volume, sperm concentration, sperm motility, total sperm count and total motile sperm are all associated with a higher risk of death. Men with two or more abnormal semen parameters had a 2.3-fold increase risk of dying younger compared with men with normal semen, states the study.

"Could it be that something about the experience of having and raising kids - even though you may sometimes feel like they're killing you - actually lowers mortality?" said Dr. Michael Eisenberg, assistant professor of urology who led the Stanford University school of Medicine study, in a press release.

"It's plausible that, even though we didn't detect it, infertility may be caused by pre-existing general health problems," Eisenberg said. The true cause of increased mortality risk, then, would be not infertility but those health problems, states the release.

The study may indicate that semen quality is a marker of health, stated the study's authors who are continuing the research focus.

"Is their blood pressure rising? What about their blood sugar, or other measures? We are starting to do prospective data collections now, through a collaboration involving several centers in the United States and Canada," Eisenberg said.

Stanford co-authors of the study were Barry Behr, PhD, professor of obstetrics and gynecology; Mark Cullen, MD, professor of medicine; and Shufeng Li, a statistical programmer. Researchers from Baylor and Yale University also contributed to the study, which was funded by the National Institutes of Health.