The organic bone matrix contains glycosaminoglycans (GAGs). Structural changes in bones with inflammatory and degenerative processes generally lead to the break-down of macromolecules from connective tissue and increase their urinary excretion. In the present study, the levels of urinary GAGs were investigated in 28 healthy controls consisting of 18 premenopausal and 10 postmenopausal women and 25 patients with postmenopausal and 10 postmenopausal women and in 25 patients with postmenopausal osteoporosis. Urinary GAGs were measured in 24 hour collected urine samples by the carbazole method and corrected for the excretion level of creatinine. There was a significant increase in GAGs excretion in patients with postmenopausal osteoporosis compared with healthy premenopausal (p