Estradiol and non-REM sleep attenuate physiological and emotional responses to social-evaluative stress in healthy women

Background This study examined whether individual differences in estradiol and sleep predict autonomic and cognitive responses to social-evaluative stress in healthy young women. Methods Forty-two healthy women underwent overnight in-laboratory sleep monitoring, followed by a social-evaluative stress task the next morning, which involved listening to a playback of their own karaoke singing. Pre-task estradiol levels were measured via blood sampling. Autonomic responses were assessed using pupil dilation during the playback, while cognitive responses were indexed by subjective stress ratings collected immediately afterward. Results Higher estradiol concentrations (range: 40–1129 pmol/L) were associated with reduced peak pupil dilation (range: 0.21–1.70 mm above the 95% confidence interval upper bound of baseline) and cumulative pupil dilation (total pupil expansion exceeding the individual baseline over 45 s; range: 64–3139 mm, p < 0.001), indicating lower autonomic arousal. In contrast, estradiol was not associated with subjective stress ratings (range: 10–98 mm on a 100-mm scale). Greater N3 sleep duration (range: 27–172 min), but not N1 or N2, was associated with lower subjective stress ( p = 0.032), whereas REM sleep duration (range: 53–152 min) showed no association with either outcome. None of the sleep measures was significantly related to pupillometry outcomes, and no interaction effects were observed between estradiol and sleep measures. Conclusions Estradiol and N3 sleep appear to independently modulate distinct facets of the response to social-evaluative stress: higher estradiol levels were associated with reduced autonomic arousal, while greater N3 sleep duration was linked to lower subjective stress. By revealing parallel pathways through which estradiol and sleep shape physiological and cognitive reactions to stress, this work contributes to a more nuanced understanding of the biological factors that may influence mental health and stress resilience.