<br>        Inclusion Criteria:<br><br>          -  Age between 60 and 75 years<br><br>          -  Menopause > 5 years<br><br>          -  Spine (L1 - L4) or hip BMD = -2.0 and > -3.5 SD T-score measured by DXA<br><br>          -  Patients who, in the opinion of the investigator, are able and willing to comply with<br>             the protocol for its duration<br><br>          -  Written informed consent<br><br>          -  3DpQCT measurable at both skeletal sites, distal tibia and radius<br><br>        Exclusion Criteria:<br><br>          -  Spine or hip BMD = -3,5 SD T-Score measured by DXA<br><br>          -  Vertebral fractures<br><br>          -  Multiple (>2) low trauma peripheral fractures<br><br>          -  Disease/disorder known to influence bone metabolism<br><br>          -  History of major upper gastro-intestinal (GI) disease<br><br>          -  Diagnosed malignant disease within the previous 10 years<br><br>          -  Previous treatment with a bisphoshonate at any time<br><br>          -  Treatment with fluoride for osteoporosis (dose greater than 10 mg/day) within the<br>             last 12 months, or for more than 2 years (total duration)<br><br>          -  Treatment with PTH and similar agents or strontium ranelate at any time<br><br>          -  Treatment with other drugs affecting bone metabolism within the last 6 months<br><br>          -  Chronic systemic corticosteroid treatment<br><br>          -  Estrogens, progestins, SERMs, anabolic steroids, active vitamin D<br>             analogues/metabolites, calcitonin<br><br>          -  Calcineurin inhibitors (e.g. cyclosporine, tacrolimus) or methotrexate<br><br>          -  Total serum calcium < 2.2 mmol/l or > 2.6 mmol/l<br><br>          -  Vitamin D deficiency (serum 25-hydroxy vitamin D < 12 ng/ ml)<br><br>          -  ALT above triple upper limit of normal range<br><br>          -  Renal impairment (serum creatinine > 210 µmol/l)<br><br>          -  Contra-indications for ibandronate, calcium or vitamin D<br><br>          -  Employees of the Centre for Muscle and Bone Research, or their relatives<br>