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Study Warns of This New Marijuana Side Effect 

Smoking marijuana while pregnant can impact a child's development and behavior, study finds.
FACT CHECKED BY Alek Korab

There's a new warning for women who smoke marijuana during pregnancy. A recent study conducted by the Proceedings of the National Academy of Sciences of the United States of America finds that children of women who smoked weed during their pregnancy are at greater risk for development and behavior issues. 

The study states, "Here we find that maternal cannabis use is associated with increased cortisol, anxiety, aggression, and hyperactivity in young children. This corresponded with widespread reductions in immune-related gene expression in the placenta which correlated with anxiety and hyperactivity. Future studies are needed to examine the effects of cannabis on immune function during pregnancy as a potential regulatory mechanism shaping neurobehavioral development." Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

Smoking marijuana while pregnant can impact a child's development

It's widely known that specific habits like drinking and smoking are harmful to do while pregnant, but not using marijuana. Yoko Nomura, a behavioral neuroscientist at Queens College, City University of New York, and a co-author of the new study, reiterates that sentiment to the New York Times

Women "tend to think smoking and drinking during pregnancy need to be avoided at all costs, but not cannabis," said Yoko Nomura, a behavioral neuroscientist at Queens College, City University of New York, and a co-author of the new study. "We have a long way to go to educate pregnant women, policymakers and even OB-GYN doctors on this issue."

The study showed a relationship between mCB and immune response gene networks in the placenta as a potential mediator of risk for anxiety-related problems in early childhood."

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The impact of maternal cannabis use

The study did not find, however, the connection between using marijuana during pregnancy and the impact on fetal and child development, but did show the other issues affecting children ages 3-6-years-old. 

"The impact of maternal cannabis use (mCB) on fetal and child development remains unclear. Here, we assessed the effects of mCB on psychosocial and physiological measures in young children along with the potential relevance of the in utero environment reflected in the placental transcriptome. Children (∼3 to 6 y) were assessed for hair hormone levels, neurobehavioral traits on the Behavioral Assessment System for Children (BASC-2) survey, and heart rate variability (HRV) at rest and during auditory startle. For a subset of children with behavioral assessments, placental specimens collected at birth were processed for RNA sequencing. Hair hormone analysis revealed increased cortisol levels in mCB children.

In addition, mCB was associated with greater anxiety, aggression, and hyperactivity. Children with mCB also showed a reduction in the high-frequency component of HRV at baseline, reflecting reduced vagal tone. In the placenta, there was reduced expression of many genes involved in immune system function including type I interferon, neutrophil, and cytokine-signaling pathways. Finally, several of these mCB-linked immune genes organized into coexpression networks that correlated with child anxiety and hyperactivity." And to get through this pandemic at your healthiest, don't miss these 35 Places You're Most Likely to Catch COVID.

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. . Read more