A big study from Curtin University in Western Australia has raised urgent questions about the hidden risks of maternal cannabis use.
The study, published in Psychiatry Research, analysed data from more than 222,600 Australian mothers and children.
The research related to women affected by Cannabis Use Disorder (CUD) — a condition marked by compulsive cannabis use.
If they continued to use cannabis during pregnancy there was increased the risk of disruptive behavioural disorders by 3.56 times, while postnatal use of cannabis in this group of people increased the risk by 2.95 times. These associations remained unaffected after adjusting for maternal smoking, alcohol use disorder, and socioeconomic status.
The study followed babies born in New South Wales, Australia, between 2003 and 2005. Mothers with CUD were categorised as the exposure group, while those without it were used for comparison. Both groups were tracked from pregnancy until their child’s first birthday to monitor hospital admissions for CUD. The study also followed the children until age 15, monitoring for hospital admissions and outpatient visits related to Disruptive Behavioural Disorders (DBDs).
DBDs are characterised by persistent patterns of defiance, hostility, and aggression. Children with these disorders often struggle with emotional regulation and social interactions, increasing their risk of several negative outcomes, including mental health issues, academic difficulties, and substance abuse.
Professor Rosa Alati, the Head of Curtin’s School of Population Health, said the study highlighted the lasting impact of maternal cannabis use on children’s mental health.
“With an estimated one in five Australian pregnant women using cannabis and disruptive behavioural disorders on the rise, our findings underscore the growing public health concern around cannabis use,” says lead researcher Abay Tadesse.
“Cannabinoid ingredients can cross the placenta and enter breast milk, potentially affecting brain development. This research provides critical evidence to help shape health policies aimed at minimising harm,” says Professor Rosa Alati, the Head of Curtin’s School of Population Health.
“While intervention strategies are essential, further genetic research is also needed to better understand the link between maternal cannabis use and childhood behavioural disorders”.
More on cannabis and maternal health.
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