Athletic amenorrhoea. An update on aetiology, complications and management.

The enormous increase in participation by women in physical recreation and sport since the early 1970s, has seen a parallel increase in research into the effects of strenuous exercise on the female neuroendocrine and reproductive systems. Oligomenorrhoea, primary or secondary amenorrhoea, altered pubertal progression, defective luteal phase, anovulation, and infertility may result, most frequently in those aerobic type activities associated with the lower bodyweight and fat percentages such as running, aerobics, and gymnastics. As well as body composition and sport specificity, intensity of training, previous menstrual history (in particular delayed menarche) and diet/eating disorders are all important associated factors. The neuroendocrinological pathogenesis to this altered menstrual function is complex and controversial; however, the evidence for accelerated bone loss in these young women with chronic hypo-oestrogenaemia is substantial. Since the first studies released in 1982 when amenorrhoeic runners' bone mineral content was measured and found equivalent to that predicted normal for 52-year-old women, further studies have proposed an association between this hypo-oestrogenaemia, reduced bone density and stress fractures. Studies so far show that this bone loss continues to occur over time, but the most rapid rate of bone loss (approximately 4%/year) occurs early on cessation of menses, thus emphasising the importance of early management in preventing bone loss occurring in young amenorrhoeic athletes. The role of calcium and oestrogen supplementation in management of the hypo-oestrogenic exercising female are unclear. The results of longitudinal studies currently under way assessing their benefits are awaited. Meanwhile an increased calcium intake to 1500mg per day should be advised and consideration of oestrogen and/or progesterone supplementation given. It is important that other causes of amenorrhoea are not overlooked in this exercising population and the diagnosis of 'athletic amenorrhoea' should not be made until a full thorough history, physical examination and blood tests have eliminated other common causes. Full dietary history and assessment for eating disorders is an essential part of this assessment.