Strenuous athletic training and anorexia are associated with a high incidence of amenorrhea. While the physiological and/or psychological stressors that contribute to the development of menstrual dysfunction in these individuals appear to differ, they both involve disorders of the reproductive system that originate in the hypothalamus. The available data suggest that both groups experience alterations in the pulsatile release of GnRH, which in turn produces perturbations in pituitary and ovarian function ultimately leading to menstrual dysfunction. In this review, the reproductive and "stress" hormone profiles in amenorrheic athletes and anorexic patients are compared, and the interaction of these hormonal axes in the occurrence of menstrual dysfunction is discussed.