The investigators will enroll 40 female, postmenopausal, patients with T1DM, fracturing or non-fracturing, who are age 50 and over, and have had diabetes for more than ten years. The investigators will perform 2 transiliac (hip bone) biopsies on each subject, one for mechanical testing, tissue analysis of AGEs, enzymatic crosslinks and bone tissue-bound water in cortical bone, and the other for histomorphometry and high-resolution 3D imaging in trabecular bone. A matched, non-diabetic, healthy control will be enrolled at the time each T1DM is enrolled.