Fracture frequency and bone preservation in postmenopausal women treated with estrogen.

Two hundred eighty-five normal 70-year-old Danish women were divided according to postmenopausal use of gonadal hormones into 3 groups: 1 virtually untreated (3 months or less, N = 231), 1 treated over a short term (4 months to 6 years, N = 36), and 1 treated over a long term (6 years or more, N = 18). The 3 groups had been treated for a median of 0, 6, and 70%, respectively, of their postmenopausal years. The degree of bone loss varied inversely with the duration of postmenopausal hormone treatment. Bone mineral content was 11.8% higher in the long-term treated group than in the untreated group (P less than .05). Likewise, the metacarpal bone mass was 8.5% greater (P less than .01). The number of women with postmenopausal fractures was 13% lower in the long-term treated group than in the untreated group (Difference not significant). Data from this retrospective study present evidence that estrogen protects bones in elderly women.