REM sleep deprivation during mid-pregnancy alters exploratory behaviors in dams and induces locomotor hyperactivity in mouse offspring.

Rodents exhibit exploratory behaviors, such as rearing and digging, in both novel and familiar environments, which serve to monitor their surroundings. Variations in these exploratory behaviors can serve as sensitive indicators of subtle behavioral effects induced by stressors, including sleep deprivation. Disrupted maternal sleep during gestation has been consistently associated with adverse behavioral outcomes in both the mother and her offspring. Several studies have reported that sleep restriction in late pregnancy increases ultrasonic vocalizations, promotes greater novelty-seeking and risk-taking, and increases activity levels in juvenile and adolescent rodents. However, the neonatal stage remains relatively understudied, despite its critical importance for sensory and motor development. Pregnant BALB/c mice underwent a standardized sleep-deprivation protocol for seven consecutive days (gestational days, GD7-14). Behavioral assessments were conducted in home-cage conditions immediately post-deprivation (GD14), during the recovery phase (GD18), and during the postpartum period (PPD3). Early locomotor behavior was evaluated in offspring of sleep-deprived dams using an open-field test on postnatal day 7 (PND7). Dams exhibited marked increases in mobility, rearing, grid climbing, digging, and spontaneous jumping during the sleep-deprivation days (n = 13 dams) compared with controls (n = 6 dams), with these effects persisting during the recovery period. In the postgestational period, a subset of these dams (n = 5) who delivered viable offspring normalized the frequency of these behaviors, but another subset of sleep-deprived dams who experienced miscarriage (n = 8) persisted with a higher frequency of rearing. Notably, offspring born to sleep-deprived dams showed significant locomotor hyperactivity in an open-field test compared with their controls (n = 15 pups per group). These results highlight that gestational sleep deprivation not only alters maternal exploratory patterns but also programs early offspring locomotor hyperactivity, underscoring its lasting impact on behavioral development.