Variability of bedtime in infancy and its relationship to parent-reported and auto-videosomnography sleep metrics

Early and consistent bedtimes are well-established pillars of pediatric sleep health, yet the bidirectional relationship between bedtime variability and sleep outcomes in early childhood remains understudied. This study examines associations between bedtime variability, sleep duration, nighttime awakenings, parental interventions, bedtime difficulties, and overall sleep quality in children aged 4–24 months. A total of 837 parents participated, with infant sleep objectively measured in the home using auto-videosomnography over two weeks. Parents also reported on sleep habits using the Brief Infant Sleep Questionnaire – Revised. Linear regression analyses revealed that greater bedtime variability was significantly associated with shorter total sleep time, as measured by both auto-videosomnography (β = −0.73 ± 0.087, p < 0.001) and parent reports (β = −0.30 ± 0.12, p = 0.01). While bedtime variability was not linked to nighttime awakenings, it was associated with increased parental visits (β = 0.61 ± 0.16, p < 0.001). Additionally, greater bedtime variability correlated with more bedtime difficulties (β = 0.28 ± 0.10, p = 0.004), though it was not directly associated with overall sleep quality. These findings underscore the importance of maintaining consistent bedtimes to support optimal sleep duration and bedtime ease in infancy, with potential benefits for broader developmental outcomes.