Few studies have explored the association between maternal gestational cannabis use and disruptive behavioural disorders (DBDs) in offspring, often relying on self-reported data and small samples. This study aimed to assess the relationship between maternal cannabis use disorder (CUD) during pregnancy and postpartum periods and the risk of disruptive behaviours in offspring. We conducted a population-based retrospective cohort study using linked health data from New South Wales, Australia, for live births between 2003 and 2005. Mothers with CUD were compared to those without, and the risk of DBDs in offspring was estimated. Both CUD and disruptive behavioural disorders were identified using the International Classification of Disease (ICD) codes. Generalised Linear Models (GLMs) with log-binomial regression were fitted to estimate disruptive behavioural disorder risk in children. Statistical significance was set at p < 0.05.
After adjusting for key confounders, this study revealed significantly higher risks of disruptive behavioural disorders in children of mothers with CUD during the antenatal [risk ratio (RR) = 3.56, 95 % CI 2.42–5.05], perinatal [RR = 3.55, 95 % CI 2.45–4.98], and postnatal [RR = 2.95, 95 % CI 1.23–6.16] periods compared to non-exposed counterparts. These findings underscore the importance of preconception, antenatal, and postnatal counselling on maternal cannabis use to mitigate neurobehavioral risks in children.