Total and regional bone mineral content in normal premenopausal women.

In the present, cross-section study, a total of 185 normal premenopausal females--aged 15 through 19 years (n = 40), 20 to 29 years (n = 60), 30 through 39 years (n = 40) and 40 to 49 years (n = 45)--were assessed in order to observe and evaluate the total body bone mineral content and the regional body mineral content of different anatomical regions (head, trunk, arms and legs), when the bone mass peak is established in women and its course during premenopause. All subjects underwent bone densitometry with dual energy X-ray absorptiometry with a Norland XR-26 bone densitometer. No differences between groups were found in total body bone mineral and regional bone mineral content values. Total body bone mineral values (mean +/- SD) were 2546 +/- 461 g and 2691 +/- 499 g in the 15-19 year-old group and 40-49 year-old group respectively. The regional bone mineral content values for the same age group were 495 +/- 75 g and 499 +/- 89 g for the head, 1007 +/- 254 g and 1043 +/- 212 g for the trunk, 327 +/- 74 g and 336 +/- 81 for the arms, and 860 +/- 167 g and 811 +/- 146 g for the legs. The results of this study indicate that the peak bone mass is reached at the age of 20 years and that it remains stable in the premenopausal eugonadal females.