A bone densitometry scan is a quick and accurate test similar to an X-ray that measures the density of your bones. It is mainly used to detect conditions like osteopenia and osteoporosis, which are characterized by low bone mineral density and an increased risk of fractures. If you are or might be pregnant, inform your doctor before undergoing this test. You can continue your usual daily activities and take your regular medications before the test, but avoid calcium supplements for 24 hours prior. During the scan, you will lie on a padded table while the lumbar spine and hip are examined. The test results are typically available within 24 hours and will be discussed with you by your doctor.