DHEA-S µg/dL to µmol/L Converter

DHEA-S in two units: the short answer

To convert DHEA-S (dehydroepiandrosterone sulfate) from µg/dL (mcg/dL) to µmol/L, multiply by 0.02714 (or divide by 36.85). To convert µmol/L back to µg/dL, multiply by 36.85. A DHEA-S of 200 µg/dL is therefore 5.4 µmol/L, and 8.0 µmol/L is 295 µg/dL. The converter above handles both directions and shows typical ranges for young adult men and women.

DHEA-S is a hormone whose normal range changes dramatically with age: it rises in late childhood, peaks in the twenties and then falls steadily, so that an 80-year-old may have a fifth of the level of a 25-year-old. Combined with the difference in units – values of a few hundred in µg/dL versus single figures in µmol/L – this makes it a test where both conversion and age-matching are essential. This guide explains what DHEA-S is, how to convert it, how to read it by age and sex, and when it is useful.

What DHEA-S is

Dehydroepiandrosterone (DHEA) is a steroid hormone produced mainly by the zona reticularis of the adrenal cortex, with small contributions from the ovaries and testes. Most DHEA is converted to its sulfated form, DHEA-S, which circulates at much higher concentrations and is very stable, with a half-life of about 10–20 hours, compared with minutes for DHEA. Because of this stability and its lack of a strong daily rhythm, DHEA-S is the preferred test for assessing adrenal androgen production.

DHEA and DHEA-S are weak androgens on their own. Their importance lies in being converted in tissues into more potent hormones – testosterone and dihydrotestosterone, and estrogens. In women, adrenal DHEA-S is a significant source of androgens; in men, the testes produce far more testosterone, so DHEA-S contributes relatively little.

DHEA-S production is stimulated by ACTH from the pituitary, the same hormone that drives cortisol production, but the two do not always move together.

µg/dL and µmol/L explained

• µg/dL (micrograms per deciliter), also written mcg/dL – the usual US unit.
• µmol/L (micromoles per liter) – the SI unit used in the UK, Europe, Australia and elsewhere.

Some laboratories report DHEA-S in ng/mL (1 µg/dL = 10 ng/mL) or µg/L. DHEA (unsulfated) is a separate test, usually reported in ng/dL or nmol/L, with much lower values.

Why the factor is 0.02714

DHEA sulfate has a molar mass of about 368.5 g/mol. A concentration of 1 µg/dL is 10 µg per liter, which is 10 ÷ 368.5 = 0.02714 µmol/L. Conversely, 1 µmol/L = 36.85 µg/dL.

How to convert DHEA-S step by step

1. Check whether the test is DHEA-S (sulfate) or DHEA, and note the unit.
2. If the result is in ng/mL, divide by 10 to get µg/dL.
3. For µg/dL to µmol/L, multiply by 0.02714.
4. For µmol/L to µg/dL, multiply by 36.85.
5. Round µmol/L to one decimal place and µg/dL to whole numbers.

Worked examples

• 65 µg/dL × 0.02714 = 1.8 µmol/L – the lower end of a typical range for women in their twenties.
• 150 µg/dL × 0.02714 = 4.1 µmol/L.
• 380 µg/dL × 0.02714 = 10.3 µmol/L – the upper end of a typical range for women in their twenties.
• 640 µg/dL × 0.02714 = 17.4 µmol/L – the upper end of a typical range for men in their twenties.
• 700 µg/dL × 0.02714 = 19.0 µmol/L – a level that warrants investigation in a woman.
• 3.0 µmol/L × 36.85 = 111 µg/dL.
• 12 µmol/L × 36.85 = 442 µg/dL.
• 2,500 ng/mL = 250 µg/dL × 0.02714 = 6.8 µmol/L.

Mental shortcut

Divide µg/dL by 37, or multiply µmol/L by 37. For 300 µg/dL: 300 ÷ 37 = 8.1 µmol/L (exact: 8.1).

DHEA-S conversion chart

Normal DHEA-S ranges by age and sex

DHEA-S ranges depend strongly on age and sex. The following are illustrative ranges; laboratory ranges vary.

Childhood and adrenarche

DHEA-S is very high in newborns (produced by the fetal adrenal zone), falls quickly in the first months, and remains low through early childhood. Around ages 6–8 it begins to rise – a process called adrenarche – which leads to the appearance of body odour, oily skin and, later, pubic and underarm hair. Premature adrenarche, with these signs appearing before age 8 in girls or 9 in boys, is usually benign but is evaluated to exclude other causes of early puberty or androgen excess.

Decline with age

After peaking in the mid-twenties, DHEA-S falls by roughly 2–3% per year, a process sometimes called "adrenopause". This decline led to interest in DHEA supplements as an "anti-ageing" treatment (see below).

When DHEA-S is measured

DHEA-S is not a routine test. It is ordered in specific situations:

• Signs of androgen excess in women – excess hair growth (hirsutism), acne, thinning scalp hair, irregular periods, or more marked virilisation (deepening voice, increased muscle mass, enlarged clitoris). It helps identify whether the adrenal glands are a source of excess androgens.
• Polycystic ovary syndrome (PCOS) – DHEA-S is mildly raised in about 20–30% of women with PCOS. It may be measured as part of the work-up, mainly to help exclude other causes.
• Suspected adrenal tumours – adrenocortical carcinomas often produce large amounts of DHEA-S. A very high level, particularly above about 600–700 µg/dL (16–19 µmol/L) in a woman, raises concern and warrants imaging.
• Congenital adrenal hyperplasia (CAH) – in some forms, DHEA-S is raised, although 17-hydroxyprogesterone is the main test for the commonest type.
• Early or delayed puberty in children.
• Adrenal insufficiency – DHEA-S is low in both primary and secondary adrenal insufficiency, and a normal age-appropriate DHEA-S makes significant adrenal insufficiency less likely, although it is not diagnostic on its own.
• Incidentally found adrenal masses (incidentalomas) – a low DHEA-S can support a diagnosis of mild autonomous cortisol secretion, as excess cortisol suppresses ACTH and therefore adrenal androgen production.

High DHEA-S

Causes of a raised DHEA-S include:

• PCOS – usually mild elevations.
• Non-classic congenital adrenal hyperplasia.
• Adrenal tumours – adenomas occasionally, carcinomas more often; very high values are a red flag.
• Cushing's disease (ACTH-dependent) – ACTH stimulates DHEA-S as well as cortisol.
• DHEA supplements – readily raise DHEA-S, often above the reference range.
• Stress and some medicines can cause modest changes.

The speed of onset matters: androgen excess that develops rapidly over months, or virilisation, is more concerning for a tumour than slowly progressive mild hirsutism since puberty.

Low DHEA-S

Low DHEA-S may be seen with:

• Ageing – the normal decline.
• Adrenal insufficiency – primary (Addison's disease) or secondary (pituitary disease, long-term steroid treatment).
• Glucocorticoid medicines – oral, inhaled and other steroids suppress ACTH and therefore DHEA-S.
• Severe chronic illness and anorexia nervosa.
• Mild autonomous cortisol secretion from an adrenal adenoma.

How DHEA-S fits into the assessment of hirsutism

The Endocrine Society's guideline on hirsutism recommends testing for raised androgens in women with moderate or severe hirsutism, or hirsutism of any degree when it starts suddenly, progresses rapidly, or comes with other features such as irregular periods, obesity or clitoral enlargement. A typical approach is:

1. Measure total testosterone (ideally by a high-quality assay, early morning, in the early follicular phase if cycles are regular), often with SHBG to calculate free testosterone.
2. If testosterone is raised or clinical features suggest an adrenal source, add DHEA-S.
3. Measure 17-hydroxyprogesterone to screen for non-classic congenital adrenal hyperplasia, particularly in high-risk populations.
4. Check prolactin and TSH where periods are irregular.
5. If testosterone or DHEA-S is markedly raised, or there are signs of virilisation, arrange imaging of the ovaries and adrenal glands to look for a tumour.

In this sequence, a markedly raised DHEA-S with a normal or mildly raised testosterone points towards the adrenal glands, while a high testosterone with a normal DHEA-S points more towards the ovaries. Most women with hirsutism turn out to have PCOS or idiopathic hirsutism.

DHEA-S and adrenal incidentalomas

Adrenal masses are found incidentally on about 1–7% of abdominal CT scans, more often in older adults. European guidelines recommend checking every incidentaloma for excess cortisol with a 1 mg dexamethasone suppression test. A low DHEA-S for age and sex can support a finding of mild autonomous cortisol secretion, because excess cortisol suppresses ACTH, which in turn reduces adrenal androgen production. Conversely, a high DHEA-S with a large or irregular adrenal mass raises concern for adrenocortical carcinoma, which commonly produces several steroid hormones; guidelines recommend a steroid profile in these cases.

DHEA supplements

DHEA is sold as a dietary supplement in the United States, where it is not regulated as a medicine, and is prescription-only or restricted in many other countries. It is also on the World Anti-Doping Agency prohibited list. Claims that DHEA slows ageing, builds muscle or improves wellbeing are not well supported by trials in healthy older adults. Some evidence supports DHEA in specific situations – for example, the Endocrine Society suggests a trial of DHEA may be considered in women with primary adrenal insufficiency who have low libido or low mood despite optimised glucocorticoid and mineralocorticoid replacement, stopping it if there is no benefit after about six months. Vaginal prasterone (DHEA) is approved in some countries for menopausal vaginal dryness and painful intercourse.

Side effects of oral DHEA include acne, oily skin, hair growth and hair loss in women, and potentially breast enlargement in men. Its long-term safety is not established. Taking DHEA will raise DHEA-S on blood tests, so mention it to your clinician before testing.

DHEA-S in men

In men, DHEA-S is measured less often, because the testes produce most androgens. It may be checked in boys with early puberty, in men with an adrenal mass, or when adrenal insufficiency is suspected. A very high DHEA-S in a man is uncommon and, as in women, warrants evaluation for an adrenal source. Men taking DHEA supplements may see a rise in DHEA-S, oestradiol and sometimes breast tenderness, while effects on testosterone are usually small.

What affects DHEA-S results

• Age and sex – the largest influences; always use age- and sex-specific ranges.
• DHEA supplements – raise levels substantially.
• Glucocorticoids – lower levels.
• Pregnancy – DHEA-S falls in pregnancy as the placenta uses it to make oestrogens.
• Obesity and insulin resistance – modest associations.
• Assay method – immunoassays and LC-MS/MS can give different results; cross-reactivity with other steroids is less of a problem for DHEA-S than for many hormones because of its high concentration.
• Time of day – DHEA-S has little daily variation, unlike DHEA and cortisol, so timing is less critical.

Comparing DHEA-S results across laboratories

Because DHEA-S ranges depend on age, comparing results years apart requires care: a fall from 250 µg/dL (6.8 µmol/L) at 30 to 150 µg/dL (4.1 µmol/L) at 45 is consistent with normal ageing. When results come from different countries, convert first, then compare each with its own age-specific range. For example, 7.5 µmol/L in a 25-year-old woman from a European laboratory is 276 µg/dL, which sits comfortably within a typical US range for her age even though the European laboratory's numerical range looks very different.

When to see a doctor

See a doctor if you are a woman with new or worsening excess hair growth, severe acne, irregular periods or thinning scalp hair, or if you notice signs of virilisation such as a deepening voice or increased muscle bulk, particularly if they develop over months. Children with signs of puberty before age 8 (girls) or 9 (boys) should be assessed. Seek prompt assessment if a DHEA-S result is markedly raised, or if you have symptoms of adrenal insufficiency such as fatigue, weight loss, dizziness on standing and salt craving.