Sept. 26, 2011 -- Men who remain childless throughout their lives may be more likely to die from heart disease and stroke than men who become fathers, a new study suggests.

Researchers followed more than 135,000 older men for a decade in an effort to examine the impact of fatherhood on health.

They found that childless men and men with just one child were more likely to die from cardiovascular causes such as heart attack and stroke than men who fathered more than one child, study researcher Michael L. Eisenberg, MD, tells WebMD.

It is not clear from the study if parenthood has a direct impact on heart attack and stroke risk, or, if it does, if that impact is related to biology or differences in lifestyle.

All of the men in the analysis were married or had been married, but whether they remained childless by choice or because of infertility issues was not known.

"Surveys suggest that about 75% of childless, married men want to have children, so it may be that many of the men in our group were infertile," Eisenberg says.

He says that hormonal issues that lead to infertility may also affect heart and vascular disease risk.