Cortisol
Cortisol should ideally be measured between 08:00 and 09:00, when levels are normally at their highest.
Cortisol testing does not need to be scheduled around a particular menstrual-cycle day, including where cycles are irregular.
For repeat testing, samples should be collected at approximately the same time of day to allow meaningful comparison.
DHEA-S
DHEA-S does not require menstrual-cycle timing and can be measured at any time of day in both male and female patients.
Where DHEA-S is included as part of a comprehensive hormone panel, morning sampling is preferred for consistency with the other endocrine markers being assessed.
For repeat monitoring, samples should ideally be collected at approximately the same time of day.
Where the patient is taking DHEA or another androgenic supplement, the dose, timing of the most recent dose and duration of use should be documented, as supplementation can significantly influence DHEA-S concentrations.
DHEA-S should be interpreted in conjunction with age, sex, clinical presentation and other relevant androgen markers, rather than as an isolated measure of androgen status.