With quantification techniques of the spinal bone condition, especially with spinal biphotonic absorptiometry, early screening of patients risking subsequent development of osteoporosis complicated with vertebral compression is possible. An investigation was conducted in Lower Normandy, in 386 women who had undergone menopause or an ovariectomy, with ages ranging between 40 and 56 years; 274 were in a peri-menopausal state. We had previously established a curve of the bone mineral content according to age. From this curve, in semilogarhythmic representation, we assessed each patient's risk. This risk is considered as high in 30 p. cent of the patients, non existent in 52 p. cent and 18 p. cent are borderline. The percentage of high risk patients increases with the number of years since menopause. It is hoped that the incidence of osteoporosis will decrease with early screening and preventive therapeutic measures.