Cortisol
The preferred window is 08:00–09:00, when Cortisol is normally near its daily peak. Repeat measurements should be taken at approximately the same time.
Cortisol sampling does not need to be arranged for a particular menstrual-cycle day, including where cycles are irregular. The actual sample time should be recorded. A morning result is not a complete measure of chronic stress or daily cortisol production.
DHEA-S
DHEA-S can be measured at any time of day and does not require menstrual-cycle timing. Where it forms part of a broader hormone panel, morning sampling is preferred for consistency with the other markers. Repeat tests should ideally be at a similar time.
Disclose DHEA and other androgenic supplements, including dose, most recent dose time and duration of use. These can substantially alter the result.
Age, sex, symptoms and other androgen measurements guide interpretation. DHEA-S is not an isolated measure of overall androgen health.