Estrogen replacement prevents worsening body dissatisfaction with weight gain in adolescents with anorexia nervosa. However, the impact of estrogen administration on eating disorder (ED) pathology in normal-weight young women with exercise-induced amenorrhea is unknown. We hypothesized that (1) normal-weight oligo-amenorrheic athletes (OA) would show greater ED pathology than eumenorrheic athletes (EA) and non-athletes (NA), and (2) 12 months of estrogen replacement would improve those symptoms.