Investigators from Columbia University’s Mailman School of Public Health and Rutgers School of Public Health say stress affects semen quality, affecting its concentration and appearance.
According to the American Society for Reproductive Medicine, infertility affects men and women equally, and semen quality is a key indicator of male fertility.
“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,” said senior author Pam Factor-Litvak, Ph.D. “These deficits could be associated with fertility problems.”
Study results are published online in the journal Fertility and Sterility.
Researchers followed 193 men, ages 38 to 49, enrolled in the Study of the Environment and Reproduction at the Kaiser Foundation Health Plan in Oakland, Calif., between 2005 and 2008.
The men completed tests to measure work and life stress on subjective scale (how they felt overall) and objective scale (life events behind the stress). They also provided semen samples.
Technicians at the University of California, Davis, used standard methods employed in fertility testing to assess the samples for semen concentration, and sperm appearance and motility.
Measured subjectively or objectively, life stress degraded semen quality, even after accounting for men’s concerns about their fertility, their history of reproductive health problems, or their other health issues.
Surprisingly, workplace stress was not a factor. However, researchers believe it may still affect reproductive health since men with job strain had diminished levels of testosterone. Not having a job was associated with having sperm of lower quality than employed men, regardless of how stressed they were.
Researchers are unsure how stress affects semen quality. It may trigger the release of steroid hormones called glucocorticoids, which in turn could blunt levels of testosterone and sperm production.
Another possibility is oxidative stress, which has been shown 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,” said Teresa Janevic, Ph.D., the study’s first author.
While several previous studies have examined the link between stress and semen quality, the current paper is the first to look at subjective and objective measures of stress and find associations with semen concentration, and sperm appearance and motility.