DHEA-S
Dehydroepiandrosterone sulfate
What it is
DHEA-S (dehydroepiandrosterone sulfate) is an androgen produced almost exclusively (over 95%) by the adrenal glands. It is the sulphated, storage form of DHEA — more stable in the bloodstream and therefore more reliable to measure. Unlike testosterone or free DHEA, DHEA-S does not fluctuate significantly across the menstrual cycle or with time of day, making it a practical marker that can be drawn at any point without phase or fasting constraints (though fasting is sometimes recommended for standardisation).
DHEA-S is part of the standard hormone panel ordered when investigating hyperandrogenism, and is specifically used to help distinguish ovarian (PCOS) from adrenal origins of elevated androgens.
Why it matters in PCOS
Approximately 20–30% of people with PCOS have a mildly elevated DHEA-S. This modest elevation is consistent with PCOS, which can involve mild adrenal androgen overactivity alongside the ovarian hyperandrogenism that is the hallmark of the condition.
A mildly or moderately elevated DHEA-S in a typical PCOS presentation does not undermine the diagnosis. However, a level above 700–800 µg/dL is a red flag: it raises suspicion for an adrenal secreting tumour or non-classic congenital adrenal hyperplasia (CAH), both of which can closely mimic PCOS. Further investigation is required in those cases.
An important distinction: DHEA-S is not the same as free DHEA. Free DHEA fluctuates more, is less reproducible, and is rarely measured in routine clinical practice. DHEA-S is the recommended marker for standardised PCOS workup panels.
Normal values
Reference ranges vary by age and laboratory. Indicative values for women:
- 18–29 years: 65–380 µg/dL
- 30–39 years: 45–270 µg/dL
- 40–49 years: 32–240 µg/dL
- Alert threshold (adrenal tumour concern): > 700–800 µg/dL
DHEA-S naturally declines with age. A result in the upper normal range at age 22 carries different significance than the same value at age 45.
When is it measured?
DHEA-S is drawn as part of the initial workup for suspected PCOS or when investigating hyperandrogenism (excess hair growth, acne, androgenic alopecia). No specific cycle day is required. Some labs recommend fasting to standardise conditions, but this is not universally mandated. Results should always be interpreted alongside other androgens (total testosterone, free testosterone) and the full clinical picture.
Key takeaways
- Adrenal androgen — stable, can be drawn at any cycle phase
- Mildly elevated in 20–30% of PCOS — compatible with the diagnosis
- Level > 700–800 µg/dL: requires further workup (tumour, CAH)
- Use DHEA-S, not free DHEA, for standardised PCOS panels
- Always interpret within the full clinical context