Background: Reproductive and menstrual characteristics, as well as high circulating estrogen and androgen concentrations, are associated with the risk of breast and ovarian cancer in postmenopausal women. To explore possible etiological relationships between menstrual and reproductive characteristics and cancer risk, we examined associations between menstrual and reproductive factors and serum concentrations of total testosterone, free testosterone, androstenedione, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S).
Methods: This study was conducted in 167 postmenopausal women, using data from the pre-randomization visit of an exercise clinical trial. Participants were sedentary, overweight/ obese, and not on hormone therapy.
Results: DHEA-S concentrations were 42% higher, total testosterone concentrations were 35% lower, and free testosterone concentrations were 23% lower in women with both ovaries removed compared with those with both remaining (p = 0.01, p = 0.01, and p = 0.03, respectively). Women who had used herbal therapy in the past had, on average, 25% higher concentrations of total and free testosterone than women who had never used these herbal therapies (p = 0.03 and p = 0.004, respectively). No other significant associations were detected.
Conclusions: Overall, this study does not support the hypothesis that reproductive or menstrual factors, with the exception of oophorectomy status, are associated with postmenopausal androgen concentrations.