Do Stressed-Out Men Have Weaker Sperm?
Study does seem to show a link, but impact on fertility isn't clear
By Randy Dotinga
FRIDAY, May 30, 2014 (HealthDay News) -- A small new study suggests that higher levels of stress may hurt the quality of men's sperm, potentially making it more difficult for them to impregnate women.
The findings aren't definitive and don't prove cause-and-effect, since it's possible that stressed-out men share another trait that disrupts their reproductive systems. Also, it's not clear if men with more stress are actually less fertile.
Still, "men who reported a higher number of stressful events happening in their life, or those who reported feelings of stress, had a lower percentage of sperm that moved well or were formed correctly, as well as lower numbers of sperm," said study lead author Teresa Janevic, an assistant professor at Rutgers School of Public Health's Department of Epidemiology in Piscataway, N.J. "Lower values of each of these measures are associated with lower fertility because of their reduced ability to fertilize an egg."
Prior research has linked stress to lower quality of semen, the fluid that contains sperm. But, "the results are not consistent across studies, and this is likely due to different populations and varied methods of measuring stress in these studies," said Audra Gollenberg. She is an assistant professor of public health at Shenandoah University College of Arts and Sciences in Winchester, Va., and was not involved in the new research.
The study was designed to "really get to the bottom of the question how stress is influencing the reproductive health of average men," Janevic said.
The researchers tracked 193 healthy men aged 38 to 49 from northern California who agreed to take part in a study and provide semen samples at a clinic. The men also answered questions about their levels of overall life stress and their stress at work.
The design of the study doesn't allow the researchers to link specific levels of stress to specific effects on sperm, Janevic said. And she added that "small increases in stress may not to be important for the semen quality in any individual man."
However, the study did find that men who were stressed in general had more dysfunctional sperm. This held true even after the researchers adjusted their statistics so they wouldn't be thrown off by traits like age, education level or race.