peer reviewedDuring more than 20 years, estrogens replacement therapy (ERT) has been consistently regarded as the first choice for prevention of trabecular and cortical bone loss in postmenopausal women. However, there are more doubts upon the unequivocal demonstration of the anti-fracture efficacy of ERT, at the spine and hip. Controlled clinical trials and systematic reviews were retrieved, using Medline 1970-2002 and EMBASE 1980-2002. There is a convergent body of evidence that estrogens could significantly reduce the risk of vertebral and non-vertebral fractures, providing this treatment is started early after the menopause and pursued indefinitely. In the recent perspective of the published studies, reevaluating the non-skeletal benefits and harms of ERT in post-menopausal women, other chemical entities might be better options to be used for the specific purpose of preventing or treating post-menopausal osteoporosis