Estrogen replacement therapy continuously combined with four different dosages of dydrogesterone: effect on calcium and lipid metabolism.

Lipid and bone metabolism was studied in 165 healthy postmenopausal women treated with 2 mg 17 beta-estradiol continuously combined with one of four doses (2.5, 5, 10, or 15 mg) of dydrogesterone in a double blind randomized study design. Fasting blood and urine samples were drawn at baseline and after 3 and 6 months of treatment. Bone remodeling was significantly reduced in all four treatment groups, as indicated by the decrease in serum corrected calcium, phosphate, and alkaline phosphatase and the urinary calcium/creatinine ratio. A dose response of dydrogesterone on these indices was not found. With all four dosages of dydrogesterone, lipid profile (total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, and apolipoproteins) improved significantly; however, this was less pronounced with the highest dydrogesterone dose. Our data suggest that continuously applied dydrogesterone in combined hormone replacement therapy does not annihilate the beneficial effects on bone remodeling and lipid metabolism induced by estrogens.