Association Between Caffeinated Beverage Intake and Semen Quality in a Preconception Cohort

BACKGROUND: Few studies have examined the association between caffeine intake and semen quality among couples attempting conception. OBJECTIVES: To examine the effect of caffeinated beverage intake on semen quality. MATERIALS AND METHODS: We analyzed cross-sectional data from Pregnancy Study Online (PRESTO), a preconception cohort study. We invited US residents aged ≥ 21 years to perform at-home semen testing (n = 929 participants; 1668 samples). The outcomes included semen volume, sperm concentration, total sperm count (TSC), percent motility, and total motile sperm count (TMSC). Participants reported their past-month intakes of caffeinated coffee, tea, soda, and energy drinks, from which we calculated caffeine intake. We used multivariable linear regression to estimate mean percentage differences (%D) and 95% confidence intervals (CIs). RESULTS: Median caffeine intake was 138 mg/day (interquartile range = 51-270 mg/day). No monotonic associations were observed for intakes of coffee, tea, soda, or energy drinks. Comparing caffeine intakes of ≥ 200 versus < 100 mg/day, we found no consistent associations with semen volume (%D [95% CI]: 0.2 [-8.2, 8.6]), sperm concentration (-9.1 [-23.2, 7.5]), TSC (-10.1 [-23.7, 6.0]), % motility (2.4 [-3.5, 8.3]), or TMSC (-7.9 [-23.5, 11.0]). DISCUSSION: Caffeinated beverage intake was not consistently associated with semen parameters in this preconception cohort. CONCLUSION: Moderate caffeine intake has little effect on semen quality.