Dad and kid
A new study has found a direct link between exposure to excess stress and infertility in men.jenny downing/Flickr

It's better to stay cool if you want to become a dad. A new study has found a direct link between exposure to excess stress and infertility in men.

In a study published in the journal Fertility and Sterility, taking too much stress was found causing damages to the sperm and semen quality, upsetting its concentration, appearance and finally affecting its ability to fertilize an egg.

"Men who feel stressed are more likely to have lower concentrations of sperm in their ejaculate, and the sperm they have are more likely to be misshapen or have impaired motility," senior author of the study Dr Pam Factor-Litvak, from the Mailman School of Public Health, in the US said in a news release. "These deficits could be associated with fertility problems."

For the study, researchers selected 193 men, aged between 38 and 49, from the Study of the Environment and Reproduction at the Kaiser Foundation Health Plan in Oakland, California. The men underwent tests that measured their work and life stress, at subjective and objective scale. Later, a team of technicians evaluated quality of the semen samples collected from the men, mainly semen concentration, sperm appearance and motility.

Results showed that life stress left a lasting impact on semen quality. Though researchers couldn't find any strong link between work place stress and infertility, they found lowered testosterone levels associated with taking too much strain involved in the job. However, unemployment had the worst impact on semen quality. Sperm collected from unemployed men were of lower quality than the working men.

Though the researchers couldn't underline the exact factor that led to this occurrence, they put forward two possibilities. The first one is that exposure to stress prompts the release of steroid hormones known as glucocorticoids, that in turn affects testosterone levels and sperm production. The second one is oxidative stress, that has long been known to affect semen quality and fertility.

"Stress has long been identified as having an influence on health. Our research suggests that men's reproductive health may also be affected by their social environment," first author of the study, Dr Teresa Janevic said.

Infertility is a term used to explain the inability of a couple to conceive even after nearly two years of constant efforts. In 90 percent of the cases, low sperm count and poor sperm quality play major roles, according to experts. Apart from stress, infertility in men has been linked to many other factors including smoking, drinking alcohol, use of drugs, vitamin C and Zinc deficiency, use of tight underwear, sexually transmitted diseases, too much exercise and use of anabolic steroids.

Latest report shows that infertility is highly prevalent among Indian couple. The "Helping Families" survey, conducted by a pharmaceutical company in nine major Indian cities, found that infertility rates among Indian couple have shot up recently.