SKELETAL EFFECTS OF MENSTRUAL DISTURBANCES IN ATHLETES

This article reviews the skeletal effects and clinical implications of menstrual disturbances in active women. At the lumbar spine, menstrua l disturbances are associated with premature bone loss or failure to r each peak bone mass, while appendicular sites are less affected. This suggests that trabecular bone is more sensitive to hormonal stimuli an d less responsive to mechanical loading than cortical bone. Although t he mechanisms responsible for the detrimental effects of menstrual dis turbances are likely to be multifactorial, low circulating levels of o estrogen are thought to be the main cause. The clinical significance o f menstrual disturbances depends upon a number of factors, including t ype of sport, genetic background, body composition and calcium intake. Not all athletes who present with menstrual disturbances will develop osteopenia. Nevertheless, the risk of stress fracture does seem to be increased in athletes with menstrual disturbances and with lower bone density. Whether athletes with menstrual disturbances are at a greate r risk for osteoporosis in later life is not yet known. Bone loss can be at least partially reversed, especially with the spontaneous resump tion of menses. This may serve to offset any previous increased risk o f osteoporosis. Furthermore, other factors, apart from low bone mass, act to determine the likelihood of osteoporotic fractures. Therefore, the clinical significance of menstrual disturbances associated with ex ercise participation needs to be established for each individual athle te. Bone densitometry may guide the clinician in this respect and assi st in the formulation of appropriate management strategies.