Biomarkers of Stress and Male Fertility

To study if stress, as measured by salivary alpha-amylase and cortisol, negatively impacts male fertility, as measured by semen parameters, pregnancy, and live birth rates. Prospective, cohort study of men enrolled in the Males, Antioxidants, and Infertility (MOXI) trial. One-hundred twelve infertile men provided first-morning salivary and semen samples at baseline. Salivary samples were analyzed for alpha-amylase and cortisol. Couples attempted to conceive naturally (months 1-3) and with clomiphene citrate/intrauterine insemination (months 4-6). The association between stress-related biomarkers and semen parameters including DNA fragmentation was assessed using linear regression models adjusting for male age. Salivary levels were dichotomized at the 80th percentile. Pregnancy/live birth rates in couples in the upper quintile were compared to remaining subjects using chi-square testing. Salivary levels of alpha-amylase were not associated with semen parameters or DNA fragmentation. Salivary cortisol levels were not correlated with DNA fragmentation or normal morphology. For every 1-unit increase in salivary cortisol, total sperm count increased by 13.9 million (95% CI: 2.5, 25.3) and total motile sperm count increased by 9.9 million (95% CI: 3.2-16.6). Couple pregnancy rates and live birth rates did not differ for males in the highest quintile of alpha-amylase (27% and 28%, p = 0.96; 23% and 21%, p = 0.87) or cortisol (40% and 26%, p = 0.22; 35% and 19%, p = 0.12), compared to males with lower values. Physiologic measures of high stress may not harm but actually improve semen parameters among men with male-factor infertility.