Changes in androgen profile over the menstrual cycle and hormonal contraceptive phases in physically active females

Background: Concentrations of female sex hormones fluctuate during the menstrual cycle (MC), while hormonal contraceptives (HC) generally suppress hypothalamic-pituitary-ovarian axis function resulting in lower concentrations of endogenous estradiol (E2) and progesterone (P4). Little attention has been paid to changes in androgen concentrations during MC and HC phases. Therefore, the aim of this study was to investigate changes in androgen concentrations over the MC and HC phases. Methods: The study was a cross-sectional analysis across MC and HC phases using four time points. E2, P4, follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (tT), free testosterone (fT), sex hormone-binding globulin (SHBG), dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S) were analyzed from the serum of healthy, physically active, naturally menstruating (NM = 36), hormonal intrauterine device using (IUD = 12) and combined HCs using (CHC = 25) females. Results: In NM, concentrations of tT (β = 0.16, p = 0.050), fT (β = 1.85, p < 0.001) and DHEA (β = 5.29, p = 0.045) were significantly higher at ovulatory phase and concentrations of DHEA-S at the mid-follicular phase (β = 0.32, p = 0.012) compared to bleeding. In IUD, tT concentrations fluctuated significantly being highest at mid-cycle (β = 0.34, p = 0.001) compared to the sample defined as measurement 1 (based on bleeding and/or hormonal concentrations). In CHC, concentrations of E2, P4, tT, fT, DHEA, and DHEA-S remained unchanged between the HC phases. Conclusions: Since the endogenous hormonal milieu, including androgens, may affect female physiology, considering the fluctuation in androgen levels over the MC and HC phases may be of importance in physiological research.