0188 Impact of the Menarcheal Transition on Sleep in Biological Females

Abstract Introduction Puberty encompasses a multitude of physical, hormonal, and psychological changes. Additionally, adolescents also experience a delay in circadian rhythm, increasing their vulnerability to insufficient sleep. Even though puberty and sleep share a strong association, few studies have explored the shift in sleep after the onset of menstruation (i.e., menarche). This longitudinal, multimethod study examines sleep health parameters before and after menarche among a community sample of females. Methods Biological females (n = 47; 74% white) from a Midwestern metropolitan area were recruited as part of a larger study on menarche. Participants completed two lab visits: Time 1 (T1: prior to menarche; Mage = 11.3, SDage = 1.0) and Time 2 (T2: 3-9 months post-menarche; Mage = 12.6, SDage = 1.0). An actigraph wristwatch was worn for 7 days following each lab visit to measure dimensions of sleep health including bedtime, wake time, time in bed, and total sleep time. Phillips Actiware Software was used to score actigraphy data; SPSS 27 was used to perform paired sample t-tests to explore changes over time. Results Following menarche, there were significant differences in several parameters of sleep health including: 1) a 1.7-hour delay in bedtime (T1M = 21:45, T1SD = 1:02; T2M = 23:29, T2SD = 3:07, t(46) = (3.37), p = (.002), 2) less time in bed (T1M = 542, T1SD = :48; T2M = 518, T2SD = :58), t(46) = (2.67), p (.01), and 3) a 27-minute decrease in total sleep time (T1M = 482, T1SD = :40; T2M = 455, T2SD = :51), t(46) = (3.32), p = (.002). Overall, these results indicate participants are sleeping significantly less in the months following menarche. Conclusion Findings confirm that biological females experience changes in sleep behaviors within 9 months of menarche. Chronic sleep loss and daytime sleepiness worsens throughout adolescence, furthering the risk for cognitive and behavioral issues. Data collection is ongoing and future analyses will examine sleep variability across this transitional point in development. This is one of the first studies to examine the sleep-wake experience of females across menarche. Support (if any)