Premenopausal bone loss: fact or artifact?

Bone strength is closely related to bone mass, and sex differences in bone mass are the main reason for the greater frequency of osteoporotic fractures in elderly women than in men of the same age. Peak bone mass is lower and the subsequent rate of loss is greater in women. It has been debated whether there is a significant bone loss in women before menopause. This has been studied in cross-sectional studies with and without information on menopausal status, and in longitudinal studies following women through the menopause. The present review addresses this issue and discusses important cross-sectional and longitudinal studies on this question. The overall conclusion is that there probably is a minor premenopausal trabecular bone loss which can be found to be of statistical significance where many individuals are included in the study and very precise methods are used, but it is of a magnitude which probably is of no clinical significance.