A recent study from Stanford University suggests that men who do not have children may be at greater risk of contracting cardiovascular disease.

The results, published in the journal Human Reproduction, come from a team led by Michael Eisenberg, a professor of urology. Researchers tracked 137,903 American men who were members of the American Association of Retired Persons over 10 years. The average age of the participants was 63, and anyone with a history of heart disease or stroke was excluded.

Of the total study group, 92 percent were fathers and at least half of them had three or more children. After an average follow-up period of 10 years, approximately 10 percent of them had died.

The researchers tracked death rates from among 70 probable causes, using Social Security information and other databases, as well as sending questionnaires to surviving family members. They found a link between parental status and cardiovascular risk. But the authors stated they were not aware of a connection between infertility and an increased risk of contracting cardiovascular diseases.

Maybe having children causes men to have healthier behaviors, so fathers tend to live longer, Eisenberg said.

According to the statistics, men who have not fathered children face a 17 percent greater risk of death from cardiovascular diseases, after accounting for sociodemographic factors such as education and other risk factors for contracting heart diseases, like diabetes and Body Mass Index.

Eisenberg added that there was no way of assessing a man's reproductive intent throught his particular study.

A study from the Philippines, reported recently, found that testosterone - the principal male hormone - drops after a man becomes a father. In addition, men who started with high levels of testosterone were more likely to become fathers, suggesting that low levels might reflect an underlying health issue that prevents reproduction