“Cannabis is now the most commonly used drug, excluding alcohol and tobacco, among pregnant women in the United States and the frequency has been rising since the COVID-19 pandemic," said Dr. Amy Osborne, Senior Lecturer at the School of Biological Sciences at the University of Canterbury in New Zealand in a press release.
Cannabis use during pregnancy has significantly increased in recent years, likely due to the drug's increased legalization and decriminalization. Many studies have already shown that prenatal cannabis use increases the risk of neurodevelopmental problems. However, research that addresses the molecular effects of prenatal cannabis use is currently lacking.
To fill this gap in the research, scientists conducted an epigenome-wide association study involving two longitudinal cohorts from the UK and New Zealand. Data included self-reported answers from mothers regarding their cannabis use alongside DNA samples extracted from blood to assess differences in methylation.
“Using data from individuals at birth, aged seven, 15-17, and 27, we showed a molecular signature of prenatal cannabis exposure (PCE) in exposed individuals," said Osbourne.
“In a world-first, we identified a significant number of molecular changes in genes involved in neurodevelopment and neurodevelopmental disease, across the life course. This is a key finding because it suggests there is a molecular link between prenatal cannabis exposure and impacts on the genes involved in neurodevelopment,” she added.
The findings add to growing evidence of a causative link between prenatal cannabis exposure and negative outcomes in exposed children. The researchers hope their findings will inspire further studies with larger cohorts alongside clearer advice for pregnant women regarding the impacts of cannabis use.
Sources: Neuroscience News, Molecular Psychiatry
