- Oral Contraceptives, Menstrual Cycle and Sex Effects on Stress Responses in Adolescents.

Changes in stress reactivity are associated with psychiatric disorders and depend on sex, where men show a higher cortisol response than women. However this sex effect is dependent on hormonal state in women, as women on oral contraceptives (OC) usually show a lower stress response. To study the effect of early OC usage this study was performed in adolescents. To study the effect of sex, oral contraceptive use and menstrual cycle phase on cortisol reactivity in adolescents. Participants were drawn from the ongoing Research on Adolescent Development and Relationships (RADAR-Y) young population cohort study. 192 boys and 152 girls were included with a mean age of 17.3 years (SD = 0.44). The Leiden Public Speaking test was performed, including 8 saliva samples to assess cortisol reactivity. Among the girls, 82 were taking oral contraceptives, and among the naturally cycling (NC) girls 38 were in follicular phase and 32 in luteal phase. Adolescent boys and girls in follicular phase showed significantly larger cortisol (AUCg) response to the public speaking task than women using OCs and women in luteal phase (F(3,341)=6,49;p<0,001). Here we confirmed that adolescent girls using OCs and NC girls in luteal phase show a flattened cortisol response, compared to adolescent boys and NC girls in follicular phase. This suggests a role for progesterone and synthetic hormones on cortisol reactivity. These are preliminary results; we will also look into how the stress response can predict depressive and anxiety symptoms over 6 years follow-up.