| Purpose. The purpose of this study was to assess bone density and turnover in physically active women with menstrual dysfunction and to study relationships between hormones and bone turnover. Methods . Participants were 39 active women, aged 18-33 years. Subjects were classified as having menstrual dysfunction (AMD; 0-9 cycles·year -1), eumenorrhea (AE; 10-13 cycles·year-1), and hormonal contraceptives users (AHC; 12 cycles·year-1). Total body, lumbar spine, and hip bone mineral density (BMD) and bone mineral content (BMC) were measured using DXA (Hologic QDR-1000, Waltham, MA). Results. The AMD group had significantly lower whole body, lumbar spinal, and hip BMD than the AE group. Body weight was a positive predictor of whole body, lumbar spine, and hip BMD. The number of missed menstrual cycles associated with exercise was a negative predictor of lumbar spinal BMD, controlling for body weight. There were no significant differences in whole body, lumbar spinal, and hip BMD between the AHC and AE groups. There were no differences in markers of bone turnover or serum hormone concentrations between the AMD and AE groups. The AHC group had significantly lower progesterone and BAP and greater cortisol and concentrations compared with the AE group. Conclusion. Young, recreationally active women with menstrual dysfunction had decreased BMD compared with eumenorrheic women and age-matched norms. Hormonal contraceptive use had no effect on BMD compared to non-users. Current BMD is a cumulative effect of past behaviors and nutritional status, with maintenance of healthy menstrual function a key component of healthy bone. |
