Racial differences in sex hormone levels in women approaching the transition to menopause.

OBJECTIVE: Evaluate racial differences in reproducibility of hormone levels over time (estradiol, DHEAS, FSH, and testosterone) while adjusting for covariates previously identified as relevant in the study population.
DESIGN: Longitudinal cohort study.
SETTING: Healthy, late-reproductive-age women in a community-based sample. PATIENT(S): African American and Caucasian women identified by random digit dialing. INTERVENTION(S): Hormone levels measured in the early follicular phase of the menstrual cycle four times over 9 months. A multivariate, linear mixed model estimated effects on hormone levels of race, age at enrollment, age at menarche, number of pregnancies, current smoking, alcohol consumption, body mass index (BMI), waist/hip ratio (WHR), and menstrual cycle length. MAIN OUTCOME MEASURE(S): Follicular plasma levels of estradiol, FSH, DHEAS, and testosterone. RESULT(S): African American but not Caucasian women had significantly lower levels of estradiol and DHEAS with increasing age. African American but not Caucasian women had significantly decreased levels of estradiol and significantly increased levels of DHEAS with increasing BMI. No racial differences in reproducibility of hormone measures were found. CONCLUSION(S): There are racial differences in associations of hormone levels with age and BMI in late reproductive age women. Further study is needed to replicate these findings and to determine the relationships of these hormonal associations with menopausal symptoms.