Karen C Schliep1, Enrique F Schisterman2, Jean Wactawski-Wende3, Neil J Perkins2, Rose G Radin2, Shvetha M Zarek4, Emily M Mitchell2, Lindsey A Sjaarda2, Sunni L Mumford5. 1. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD; Department of Family and Preventive Medicine, University of Utah Health Sciences Center, Salt Lake City, UT; 2. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD; 3. Department of Epidemiology and Environmental Health, University at Buffalo, Buffalo, NY; and. 4. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD; Program of Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD. 5. Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, MD; mumfords@mail.nih.gov.
Abstract
BACKGROUND: Clinicians often recommend limiting caffeine intake while attempting to conceive; however, few studies have evaluated the associations between caffeine exposure and menstrual cycle function, and we are aware of no previous studies assessing biological dose via well-timed serum measurements. OBJECTIVES: We assessed the relation between caffeine and its metabolites and reproductive hormones in a healthy premenopausal cohort and evaluated potential effect modification by race. DESIGN: Participants (n = 259) were followed for ≤2 menstrual cycles and provided fasting blood specimens ≤8 times/cycle. Linear mixed models were used to estimate associations between serum caffeine biomarkers and geometric mean reproductive hormones, whereas Poisson regression was used to assess risk of sporadic anovulation. RESULTS: The highest compared with the lowest serum caffeine tertile was associated with lower total testosterone [27.9 ng/dL (95% CI: 26.7, 29.0 ng/dL) compared with 29.1 ng/dL (95% CI: 27.9, 30.3 ng/dL), respectively] and free testosterone [0.178 ng/mL (95% CI: 0.171, 0.185 ng/dL) compared with 0.186 ng/mL (95% CI: 0.179, 0.194 ng/dL), respectively] after adjustment for age, race, percentage of body fat, daily vigorous exercise, perceived stress, depression, dietary factors, and alcohol intake. The highest tertiles compared with the lowest tertiles of caffeine and paraxanthine were also associated with reduced risk of anovulation [adjusted RRs (aRRs): 0.39 (95% CI: 0.18, 0.87) and 0.40 (95% CI: 0.18, 0.87), respectively]. Additional adjustment for self-reported coffee intake did not alter the reproductive hormone findings and only slightly attenuated the results for serum caffeine and paraxanthine and anovulation. Although reductions in the concentrations of total testosterone and free testosterone and decreased risk of anovulation were greatest in Asian women, there was no indication of effect modification by race. CONCLUSION: Caffeine intake, irrespective of the beverage source, may be associated with reduced testosterone and improved menstrual cycle function in healthy premenopausal women.
BACKGROUND: Clinicians often recommend limiting caffeine intake while attempting to conceive; however, few studies have evaluated the associations between caffeine exposure and menstrual cycle function, and we are aware of no previous studies assessing biological dose via well-timed serum measurements. OBJECTIVES: We assessed the relation between caffeine and its metabolites and reproductive hormones in a healthy premenopausal cohort and evaluated potential effect modification by race. DESIGN:Participants (n = 259) were followed for ≤2 menstrual cycles and provided fasting blood specimens ≤8 times/cycle. Linear mixed models were used to estimate associations between serum caffeine biomarkers and geometric mean reproductive hormones, whereas Poisson regression was used to assess risk of sporadic anovulation. RESULTS: The highest compared with the lowest serum caffeine tertile was associated with lower total testosterone [27.9 ng/dL (95% CI: 26.7, 29.0 ng/dL) compared with 29.1 ng/dL (95% CI: 27.9, 30.3 ng/dL), respectively] and free testosterone [0.178 ng/mL (95% CI: 0.171, 0.185 ng/dL) compared with 0.186 ng/mL (95% CI: 0.179, 0.194 ng/dL), respectively] after adjustment for age, race, percentage of body fat, daily vigorous exercise, perceived stress, depression, dietary factors, and alcohol intake. The highest tertiles compared with the lowest tertiles of caffeine and paraxanthine were also associated with reduced risk of anovulation [adjusted RRs (aRRs): 0.39 (95% CI: 0.18, 0.87) and 0.40 (95% CI: 0.18, 0.87), respectively]. Additional adjustment for self-reported coffee intake did not alter the reproductive hormone findings and only slightly attenuated the results for serum caffeine and paraxanthine and anovulation. Although reductions in the concentrations of total testosterone and free testosterone and decreased risk of anovulation were greatest in Asian women, there was no indication of effect modification by race. CONCLUSION:Caffeine intake, irrespective of the beverage source, may be associated with reduced testosterone and improved menstrual cycle function in healthy premenopausal women.
Authors: Karen C Schliep; Enrique F Schisterman; Sunni L Mumford; Anna Z Pollack; Cuilin Zhang; Aijun Ye; Joseph B Stanford; Ahmad O Hammoud; Christina A Porucznik; Jean Wactawski-Wende Journal: Am J Clin Nutr Date: 2012-01-11 Impact factor: 7.045
Authors: Audrey J Gaskins; Alisha J Rovner; Sunni L Mumford; Edwina Yeung; Richard W Browne; Maurizio Trevisan; Neil J Perkins; Jean Wactawski-Wende; Enrique F Schisterman Journal: Am J Clin Nutr Date: 2010-10-13 Impact factor: 7.045
Authors: Kristine E Lynch; Sunni L Mumford; Karen C Schliep; Brian W Whitcomb; Shvetha M Zarek; Anna Z Pollack; Elizabeth R Bertone-Johnson; Michelle Danaher; Jean Wactawski-Wende; Audrey J Gaskins; Enrique F Schisterman Journal: Fertil Steril Date: 2014-05-27 Impact factor: 7.329
Authors: Nicole M Wedick; Aoife M Brennan; Qi Sun; Frank B Hu; Christos S Mantzoros; Rob M van Dam Journal: Nutr J Date: 2011-09-13 Impact factor: 3.271
Authors: Alexandra C Purdue-Smithe; Keewan Kim; Karen C Schliep; Elizabeth A DeVilbiss; Stefanie N Hinkle; Aijun Ye; Neil J Perkins; Lindsey A Sjaarda; Robert M Silver; Enrique F Schisterman; Sunni L Mumford Journal: Am J Clin Nutr Date: 2022-04-01 Impact factor: 7.045
Authors: Kristen J Polinski; Alexandra Purdue-Smithe; Sonia L Robinson; Sifang Kathy Zhao; Karen C Schliep; Robert M Silver; Weihua Guan; Enrique F Schisterman; Sunni L Mumford; Edwina H Yeung Journal: Am J Clin Nutr Date: 2022-02-09 Impact factor: 8.472