Menstrual status in female athletes: correlation with reproductive hormones and bone density.Obstet Gynecol. 1988 Nov; 72(5):683-7.OG
To determine whether the changes induced in serum hormone levels by strenuous exercise are accompanied by changes in bone density, we obtained medical, sports, and dietary histories, trabecular bone density, percentage body fat, and serum hormone concentrations in collegiate athletes for comparison with those of college students not involved in organized strenuous exercise. Several important observations emerged from this study of collegiate athletes. First, the eumenorrheic athletes began sports training earlier than the oligomenorrheic athletes. Second, oligomenorrheic athletes displayed significantly lower serum estradiol concentrations during cycle weeks 2 and 3 but had a rise in this hormone concentration during cycle week 4. Significant differences in serum gonadotropin concentrations during week 4 were found in the oligomenorrheic athletes. Finally, no significant difference in spinal mineral density values was found in the three groups.