EFFECT OF LONG-TERM ADMINISTRATION OF PROGESTOGEN ON POSTMENOPAUSAL BONE LOSS - RESULT OF A 2-YEAR, CONTROLLED RANDOMIZED STUDY

OBJECTIVE We determined whether a progestogen given alone to post-menopausal women may prevent bone loss. STUDY DESIGN Thirty-five early post-menopausal women who had not received any form of treatment to prevent bone loss were randomly assigned to a 2-year regimen of 500 mug/day of a gestagen derived from 19-norprogesterone (Promegestone) or a placebo for 21 days out of a 28-day treatment cycle. Bone mineral density of the spine was measured by dual photon absorptiometry. RESULTS After 2 years of treatment bone mineral density decreased significantly in the placebo group by a mean of 4.5%. In the gestagen group, the rate of bone change was significantly lower as compared to the placebo group (-1.3% +/- 1.2% vs -4.5% +/- 2% (mean +/- SEM), P < 0.05). There were no changes in the biochemical bone turnover parameters in the placebo group but in the gestagen group a significant decrease was observed in the urinary calcium excretion after 2 years. CONCLUSION The results suggest that a gestagen with no androgenic action can partly counteract early post-menopausal bone loss.