Men who feel stressed are more likely to have lower concentrations of sperm in their ejaculate and impaired sperm quality, which could be associated with fertility problems, according to a new study.1
“Our study is the first to evaluate associations between work-related stress, stressful life events, and perceived stress and semen quality. We found that perceived stress and stressful life events, but not work-related stress, were associated with semen quality,” said lead author Pam Factor-Litvak, PhD, Associate Professor of Epidemiology at the Columbia University Mailman School of Public Health in New York.
The cross-sectional study included 193 men, aged 38 to 49 years, who provided semen samples as well as information on their stressors—both objective and subjective. Objective measures of stress included reports of life events known to cause stress; subjective measures of stress included reports of how the men felt. Stress related to both life and work was evaluated.
After taking into account reproductive health history and fertility concerns, Dr Factor-Litvak and colleagues found an association between life stress and semen quality. Although work stress did not seem to be linked with semen, job strain was found to be associated with decreased testosterone, which could then affect reproductive health.
“We found an inverse association between perceived stress score and sperm concentration, motility, and morphology in covariate-adjusted linear regression analyses,” Dr Factor- Litvak said. “Men who experienced 2 or more stressful life events in the past year had a lower percentage of motile sperm and a lower percentage of morphologically normal sperm but a similar sperm concentration than men who experienced no stressful events.”
The researchers were able to examine whether neuroendocrine disruption, via testosterone or follicle-stimulating hormone, was responsible for at least part of the association. It was not. “However, these analyses were only exploratory, so we cannot say for sure that this is not one of the mechanisms,” said Dr Factor-Litvak.
Other proposed mechanisms include the stress-related production of seminal plasma reactive oxidative species, resulting in oxidative stress. “In other studies, oxidative stress is associated with semen quality and fertility,” she noted. “Clearly, more research is needed to identify all the mechanisms. There are likely to be more than one.”
The data did reveal an expected relationship between testosterone levels and semen quality; however, the data did not find associations between most stress measures and testosterone levels. “However, our analyses here were only exploratory,” Dr Factor-Litvak said. “Other studies have found associations between stress and testosterone, likely due to the effect stress has on neuroendocrine factors that influence sperm production. Those investigators posit that stress leads to increases in glucocorticoid levels, which leads to decreased testosterone production from Leydig cells, which are responsible for sperm production.”
The researchers did not study the effects of stress reduction. Nevertheless, “good health habits, including regular exercise and good dietary patterns, are advisable for all,” Dr Factor-Litvak said.
She noted that “this study found associations between life stress and unemployment, and semen quality. It is only one study, and more research is clearly needed to confirm the association and to explore the potential mechanisms.”
The researchers presented their results online on May 22, 2014 in Fertility and Sterility.
This article was originally posted 6/10/2014 and has since been updated.
1. Janevic T, kahn LG, Landsbergis P, et al. Effects of work and life stress on semen quality. Fertil Steril. 2014;102:530-538.