Oral contraceptives and the dexamethasone suppression test

Area of Science:

• Endocrinology
• Reproductive Health

Background:

• Oral contraceptives are widely used by women of reproductive age.
• Estrogen-containing oral contraceptives may influence hormonal assays.
• The effect of oral contraceptives on the dexamethasone suppression test (DST) remains understudied.

Purpose of the Study:

• To investigate the influence of estrogen-containing oral contraceptives on the results of the 1 mg dexamethasone suppression test (DST).

Main Methods:

• 1 mg DSTs were administered to two groups of healthy women: 14 taking oral contraceptives and 14 age-matched controls not taking oral contraceptives.
• Basal and post-DST cortisol levels (total and free) were measured.

Main Results:

• Women taking oral contraceptives exhibited significantly higher mean 0800h basal total cortisol levels compared to controls.
• Mean free cortisol levels did not significantly differ between the groups.
• No significant differences in DST results were observed between the oral contraceptive users and the control group at 1600h.

Conclusions:

• Oral contraceptives exert a strong influence on basal total cortisol levels.
• The use of oral contraceptives does not appear to significantly impact the results of the 1 mg DST in healthy women.