Psychological stress is harmful to sperm quality, affecting its concentration, appearance, and ability to fertilize an egg, according to a study led by researchers at Columbia University’s Mailman School of Public Health and Rutgers School of Public Health. Results are published online in the journal Fertility and Sterility.
“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,” says senior author Pam Factor-Litvak, PhD, associate professor of epidemiology at the Mailman School of Public Health. “These deficits could be associated with fertility problems.”
The researchers studied 193 men, ages 38 to 49, from 2005 to 2008. The men completed tests to measure work and life stress on a subjective scale (how they felt overall) and objective scale (life events behind the stress). They also provided semen samples.
Whether measured subjectively or objectively, life stress degraded semen quality, even after accounting for the men’s age, history of reproductive health problems, and other health issues. Although workplace stress was not a factor, the researchers say it could still affect reproductive health, as men with job strain had diminished levels of testosterone. Unemployed men had lower-quality sperm than employed men, regardless of how stressed they were.
It is not fully understood 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.
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 with sperm appearance and motility.