The influence of prenatal CBD exposure on group dynamics and social behaviors in adult offspring

Approximately 2-5% of pregnant women may use cannabidiol (CBD) on a weekly basis: an estimated 75,000 to 200,000 fetuses annually in the US alone are exposed to CBD. Identifying the impact of CBD on the developing CNS is a public health priority. CBD crosses the placenta and concentrate in breast milk. To investigate the long-term behavioral consequences of fetal CBD exposure, we compared the behavior of adult offspring from dams exposed daily to a low dose of CBD (3mg/kg s.c., E5-E18). The adult offspring was observed using Live Mouse Tracker, a methodology, based on deep learning, eliminating the need for task-specific evaluations, and minimizing experimenter interference. We identified the intricate behavioral patterns (76 behavioral traits in total) of social groups of males (n =12 controls, n = 15 CBD) or females (n = 15 controls, n = 18 CBD) mice from 4 to 6 litters. The results reveal various changes across multiple behavioral domains. Notably, during the initial activity period (night), progeny exposed to CBD demonstrated heightened interactions with littermates, observed in both males and females. However, from the second activity period onwards, male offspring exposed to CBD exhibited a reduced tendency to engage in social dyads. Regarding individual behavior, female mice displayed more frequent isolated rearing behavior, irrespective of the treatment. In summary, these findings indicate that prenatal exposure to CBD alters specific group behaviors in a sex-specific manner during the active period.