Ultra low-dose hormone replacement therapy and bone protection in postmenopausal women.

The aim of the present study was to evaluate the effects of low doses of hormone replacement therapy (HRT) in normal young postmenopausal women. In an open trial healthy, non-obese postmenopausal women received for 2 years a low-dose continuous combined HRT (LD-HRT) containing 1mg estradiol+0.5 mg norethisterone acetate each pill for 28 days, or 0.5 mg of 17beta-estradiol and 0.25 mg of norethisterone acetate (Ultra low dose, Ultra-LD-HRT) along with 1000 mg of calcium per day. Control group consisted of women receiving only 1000 mg of calcium per day, for 2 years. Menopausal symptoms were evaluated by the Green climacteric scale for the first 12 weeks of the study while bleeding profiles, bone mineral density (BMD) and bone turnover were assessed for 24 months. LD-HRT and Ultra-LD-HRT were effective in reducing menopausal clinical symptoms. In the control group, BMD significantly (P<0.05) decreased at the spine (-2.8+/-0.2%), and femoral neck (-2.8+/-0.7%). In LD-HRT treated group BMD showed a significant (P<0.05) increase at the spine (5.2+/-0.7%), and femoral neck (2.8+/-0.4%) after 24 months. In the Ultra-LD-HRT treated women spine and femoral neck BMD showed a significant (P<0.05) increase (2.0+/-0.3 and 1.8+/-0.3%, respectively) after 24 months. In these women treated with LD-HRT and Ultra-LD-HRT the BMD values were significantly (P<0.05) different from those measured in calcium-treated women. LD-HRT and Ultra-LD-HRT can alleviate subjective symptoms providing an effective protection against the postmenopausal decrease of BMD.