When Should Women Get a Bone Density Test?

In the United States, the US Preventive Services Task Force (USPSTF) recommends osteoporosis screening for women age 65 or older. Osteoporosis weakens bones and makes fractures more likely. The Task Force also recommends screening postmenopausal women younger than 65 when they have at least one risk factor and a clinical risk-assessment tool indicates increased fracture risk.

A previous fragility fracture, a bone-weakening condition or long-term use of a bone-depleting medication can call for evaluation outside routine screening. A fragility fracture is a break after a fall from standing height or less that would not usually break healthy bone. Humanic Blue keeps the paths distinct: screening looks for a problem before it is known, while diagnostic evaluation investigates a fracture or suspected bone loss.

For living longer and better, the reason to test is not to collect another score. It is to find high fracture risk early enough for evaluation and, when appropriate, treatment. A central DXA scan, a low-dose X-ray measurement of bone density at the hip and spine, is the standard test. It is quick and uses a small amount of radiation, but its result is not a complete forecast: age, falls, medications, prior fractures and other risks also matter.

When does routine bone-density screening begin?

The USPSTF’s 2025 recommendation recommends osteoporosis screening for women age 65 and older to prevent fractures. For this B-grade recommendation, the Task Force concluded with moderate certainty that screening has a moderate overall benefit. For postmenopausal women younger than 65, it recommends a two-step approach.

First, a clinician looks for one or more risk factors in addition to postmenopausal status. The USPSTF names low body weight, a parental history of hip fracture, cigarette smoking and excess alcohol consumption. Second, a validated clinical risk-assessment tool estimates whether risk is high enough to proceed to DXA.

This is not a recommendation for every woman to schedule a scan on her first day of menopause. It is also not a recommendation to wait until 65 regardless of health history. Age 65 is the routine-screening threshold; younger postmenopausal women move through a risk pathway.

The recommendation applies to adults age 40 or older without known osteoporosis or a previous fragility fracture. It does not cover people whose bone loss may come from conditions such as cancer, hyperthyroidism (an overactive thyroid) or metabolic bone disease (disorders of how the body builds or maintains bone), or from chronic use of glucocorticoids, a class of steroid medicines. These are possible causes of secondary osteoporosis—bone weakening linked to another condition or medication. Those situations need individualized clinical evaluation rather than a routine-screening calendar.

Menopause explains why risk review starts earlier than many expect

Estrogen helps regulate the ongoing replacement of old bone with new bone. The American College of Obstetricians and Gynecologists (ACOG) says the fall in estrogen around menopause triggers a period of rapid bone loss beginning about one year before the final menstrual period and lasting for roughly three years.

Researchers in the Study of Women’s Health Across the Nation (SWAN), led by geriatrician Gail Greendale, MD, followed about 900 women through the final menstrual period. Average bone-density loss was greatest from one year before to two years after that period. Most of the decline recorded across ten years happened in that three-year window (SWAN bone analysis).

Those averages do not predict one person’s loss. Body size, ancestry, medications, illness, physical activity and starting bone mass all affect the trajectory. The study also measured density, not fractures, and does not by itself prove that routine DXA during perimenopause improves outcomes.

What can call for testing before 65?

A clinician may use the FRAX tool, developed from population-based cohorts by researchers at the University of Sheffield, to estimate the chance of a hip fracture or a major osteoporotic fracture (hip, spine, wrist or shoulder) over the next ten years. FRAX combines age and other clinical factors and can be calculated with or without bone density at the femoral neck, the narrow part of the thigh bone near the hip.

The USPSTF also lists the Osteoporosis Risk Assessment Instrument and Osteoporosis Self-assessment Tool as examples. It does not endorse one universal FRAX percentage as the screening cutoff for every US woman under 65. The tool and threshold need clinical context.

Situation	What current US guidance supports	Why the route differs
Woman age 65 or older without known osteoporosis	Osteoporosis screening with central DXA, with or without fracture-risk assessment	Age alone meets the USPSTF screening recommendation
Postmenopausal woman younger than 65 with a risk factor	Clinical risk assessment first; DXA if estimated risk is increased	Not every younger postmenopausal woman receives routine imaging
Previous low-trauma or fragility fracture	Clinical evaluation rather than ordinary screening	A fracture may already indicate skeletal fragility
Long-term use of glucocorticoid steroid medicines or a bone-affecting condition	Individualized diagnostic and management pathway	The USPSTF screening recommendation excludes secondary osteoporosis
Premenopausal woman without unusual fractures or secondary risk	Routine population screening is not part of the USPSTF pathway; the clinical densitometry society identifies specific reasons for testing	The International Society for Clinical Densitometry recommends age-based Z-score comparisons rather than young-adult T-score comparisons before menopause and identifies specified risks for testing

The Bone Health and Osteoporosis Foundation also recommends DXA for women age 65 and older and for women ages 50 to 64 with risk factors. Different professional groups phrase the younger-age pathway differently, which is one reason a risk assessment is more useful than a blanket “scan at menopause” rule.

Which risk-assessment details determine the scope of the earlier-screening guidance?

A DXA scan measures density at the sites that matter most

The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), part of the US National Institutes of Health, describes central dual-energy X-ray absorptiometry—DXA or DEXA—as the most reliable way to diagnose osteoporosis and help predict fracture risk. It generally measures the hip and spine while a person lies on a padded table.

ACOG says the scan usually takes three to ten minutes and exposes a person to less radiation than a standard chest X-ray. It is noninvasive and painless.

Heel ultrasound and peripheral scans can help identify risk, but NIAMS says an abnormal heel ultrasound still requires central DXA to diagnose osteoporosis. Consumer body-composition scans may report “bone mass,” but that number is not a substitute for a clinical hip-and-spine DXA.

The T-score is useful, but it is not the whole fracture story

For postmenopausal women, DXA results are commonly expressed as a T-score—a comparison with the bone density of a healthy young adult. The number describes how far a result is above or below that reference average, in statistical units called standard deviations. It is not a percentage of bone lost. NIAMS describes the usual categories:

• −1.0 or higher: bone density in the normal range.
• Below −1.0 but above −2.5: low bone mass, often called osteopenia.
• −2.5 or lower: a result consistent with osteoporosis in the appropriate clinical setting.

Fracture risk does not begin at −2.5. The USPSTF notes that many fragility fractures occur in people whose T-scores are above the osteoporosis threshold. Age can produce very different fracture risks in two people with the same density because falls, bone quality and competing health risks also change over time.

That is the counter-case to treating the scan as a verdict. A low score deserves interpretation, but a “normal” score does not make falls irrelevant. A treatment decision may incorporate prior hip or spine fracture, calculated fracture probability, medical conditions, kidney function, medication risks and patient priorities—not only the lowest number on the report.

What does a density score leave out of a fracture-risk estimate?

When should a DXA scan be repeated?

ACOG says the interval after an initial test depends on age, the prior DXA result and individual fracture risk. Treatment monitoring follows a different schedule from repeat screening in someone whose first result was normal.

The evidence base does not support one repeat interval for everyone. The USPSTF’s 2025 evidence review found that, across five studies including about 20,000 people, repeating bone density four to eight years after the first test added little to prediction compared with the baseline result alone (USPSTF evidence summary). The review called that evidence indirect, and study quality ranged from poor to fair.

Testing too frequently can produce an apparent change smaller than a facility’s calculated least significant change—the threshold used to distinguish a likely biological change from measurement variability. The International Society for Clinical Densitometry says each facility should calculate its own precision error and that repeat intervals should be individualized. Waiting too long may be inappropriate after a fracture or a major health or medication change. The ordering clinician or osteoporosis specialist can use the baseline score and the reason for testing to set an interval.

Screening has a benefit only if the result changes care

The USPSTF describes a pathway from identifying osteoporosis to further evaluation, counseling and, when appropriate, evidence-based treatment. Screening itself does not strengthen bone.

The Task Force concluded that screening the women covered by its recommendation has a moderate net benefit, although the direct screening trials enrolled older European women and did not test DXA-only screening. Possible harms include overdiagnosis—finding low bone density that would never cause a clinical problem—and harms from subsequent treatment; evidence about the size of those harms is limited. In the one screening trial that measured anxiety, anxiety did not differ between groups over five years. DXA radiation is low, so the larger practical issue is whether the finding is interpreted correctly and leads to care that fits the person’s fracture risk.

The guideline also notes that only 40% to 60% of people who experience a hip fracture recover their previous mobility and ability to perform daily activities. That consequence—not the attractiveness of a higher score—is why fracture prevention matters.