HORMONE REPLACEMENT THERAPY IN PERIMENOPAUSAL WOMEN WITH A LOW-DOSE ORAL-CONTRACEPTIVE PREPARATION - EFFECTS ON BONE-MINERAL DENSITY AND METABOLISM

In a 2-year longitudinal, calcium-controlled study we evaluated bone d ensity and metabolism in perimenopausal women with initial ovarian fai lure, and the effects of hormone replacement with a low dose oral cont raceptive preparation (OC). In perimenopausal oligomenorrhoic women (n = 16) a significant (P < 0.01) increase in cycle length and plasma FS H levels as well as a parallel decrease in plasma estradiol levels (P < 0.01) were evident. In this group, despite the calcium supplementati on (500 mg/day), a significant ( < 0.001) increase in the biochemical. markers of bone remodelling paralleled a significant (P < 0.001) decr ease (-3.4% after 24 months) in bone density. Conversely, in premenopa usal oligomenorrhoic women treated with a low dose oral contraceptive (OC) formulation (30 meg ethinyl estradiol plus 75 meg gestodene, n = 16), bone markers showed a significant(P < 0.01) decrease, that parall eled a slight but significant (P < 0.01) increase (+1.71%) in bone den sity. These data suggest that premenopausal administration of OC can p revent the acceleration of bone turnover and reverse the decrease in b one density that follows the premenopausal impairment of ovarian funct ion.