PROTOCOL OUTLINE: Patients undergo physical examination and complete history with emphasis on risk factors for osteoporosis and screening for occult secondary causes of osteoporosis through blood serum and 24 hour urine collection.

Patients with more than 6 months since prior bone mineral density measurements or who did not receive measurements at participating center, undergo dual energy x-ray absorptiometry over 30 minutes for bone mineral density measurements.

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics--

• Low bone mass (T score less than -2.0) with no secondary cause on routine exam
• Premenopausal

OR

• Perimenopausal

--Prior/Concurrent Therapy--

• Chemotherapy: No prior or concurrent chemotherapeutic agents
• Endocrine therapy: No prior or concurrent glucocorticoids or suppressive doses of thyroid hormone
• Other: No prior or concurrent anticonvulsants

--Patient Characteristics--

• Hematopoietic: No multiple myeloma
• Other: No hyperparathyroidism No thyrotoxicosis No anorexia nervosa No Paget's disease of bone No rheumatoid arthritis No Cushing's syndrome No malabsorption syndrome No type I diabetes mellitus