0732 Poor Perinatal Sleep Quality Is Associated with an Elevated Cortisol Awakening Response

Abstract Introduction The perinatal period is a time of disrupted sleep. Sleep quality progressively worsens across gestation and into the postpartum. A mechanism linking poor sleep with certain adverse pregnancy outcomes is dysregulation of the HPA axis resulting in atypically elevated cortisol production. Although total cortisol output normally increases across pregnancy, the cortisol awakening response (CAR) attenuates as pregnancy progresses, with normalization in the first couple of weeks after delivery. The objective of this study was to evaluate longitudinal associations between maternal sleep quality and indices of cortisol across the perinatal period. Methods Data were collected as part of the HB3 study. PSQI and saliva were collected at four time-points (8-16 weeks, 30-36 weeks, 6 months postpartum, and 1-year postpartum). Participants (N = 230) who had sleep and cortisol data from at least 1 of 4 time-points were included in analyses. Multi-level models were run to predict cortisol parameters based on deviations in average maternal sleep quality at each wave. Values below the detectable limit were imputed and samples taken < 20 minutes or > 60 minutes were excluded. Results Multilevel (time, wave, and person) modeling indicated an average positive CAR slope (g=0.29, p=.02) that was affected by whether sleep quality was better or worse at that wave (p=.04). When PSQI scores were higher than the woman's own average, the CAR slope was steeper (+1 point in PSQI, g=0.32), and when scores were lower than average, the CAR slope was flatter (-1 point, g=0.25). CAR slope was not affected by average sleep quality across waves (p=.21). Diurnal slope was not affected by sleep quality being better or worse at that wave (p = .82) or by average sleep quality across waves (p=.61). Conclusion Women with poorer sleep quality than their average had a larger CAR than women with better sleep quality than their average. There was no association between sleep quality and the diurnal slope. These data suggest that greater variability in sleep quality significantly increases the amount of cortisol secreted upon awakening. Further examination is needed to determine if sleep quality is associated with adverse pregnancy/delivery outcomes via HPA axis dysregulation. Support (if any) NICHD R01HD073491-01