Twenty-six patients of mean age 37 ± 4.8 (SD) years, who received a 6-month course of gonadotropin-releasing hormone (GnRH) analogue, were selected for study. Bone mineral density (BMD) was measured by dual-photon absorptiometry before initiation and after completion of agonist therapy. Mean BMD (g/cm2) by dual-photon absorptiometry at L2 to L4, femoral neck, Ward's triangle, and the trochanteric area did not change significantly (P = not significant [NS]) after 6 months of GnRH analogue suppression. Mean percent (%) expected density as standardized for age, weight, and sex remained in the range of 89.3% to 94.2% (P = NS). The interval detectable change in BMD after therapy was 0.05 ± 0.06 g/cm2. These findings are reassuring with respect to the use of long-term GnRH analogue regimens to induce a hypoestrogenic state in the treatment of hormone-dependent conditions.