Ackerman KE, Singhal V, Slattery M, et al. - Among adolescent and young normal-weight oligo-amenorrheic athletes engaged in weight-bearing activity of the lower extremities, researchers conducted this randomized trial to analyze the impact of a transdermal and physiologic form of estrogen replacement compared with a commonly used combined oral contraceptive pill or no estrogen on changes in volumetric BMD, bone geometry and microarchitecture at the distal tibia and radius over a year. The authors discovered that bone structural parameters display greater improvement in young oligo-amenorrheic athletes after one year of treatment with transdermal 17β-estradiol vs ethinyl estradiol containing pills, especially at the tibia.