A one-year prospective comparison of calcium supplementation, low dose continuous, and moderate dose cyclical oestrogen and progestagen replacement therapy in the protection of bone mass

After 6 months of calcium supplementation, 86 recently postmenopausal women chose either to remain on calcium or to add hormone replacement therapy. Women who chose hormones were allocated at random to either a low dose continuous (conjugated oestrogens, 0-3 mg/ day and medroxyprogesterone, 2-5 mg/day) or a moderate dose cyclical (conjugated oestrogens, 0-625 mg/ day, and medroxyprogesterone, 5 mg/day) regimen. Lumbar spine bone mineral density and mass, mid radius bone mineral content, and whole body bone turnover were measured. Menopause symptoms were controlled by both hormone regimens, and both produced decreases in whole body bone turnover and increases in lumbar spine density and mass over 1 year. On calcium only, lumbar spine bone mass continued to fall. Hormone replacement also prevented an age related decrease in the serum concentration of high density lipoproteins. More than 70 per cent of the subjects on moderate dose cyclical hormones experienced bleeding problems. With low dose continuous hormones, less than 15 per cent of subjects were concerned about vaginal bleeding. Low dose continuous hormone replacement is effective in the treatment of menopause symptoms, prevents bone mineral loss and is likely to improve compliance with prophylactic hormone replacement.