Using Cannabis During Pregnancy May Give Children Stress

“Hey mom, your pot smoking is LITERALLY stressing me out!”

According to a new study, moms who use cannabis during pregnancy may inadvertently predispose their unborn children to stress and anxiety later in life. Published in the Proceedings of the National Academy of Science, the research highlights a risk that the study authors believe may become significantly more prevalent with the increasing rate of the drug’s legalization.


Although controversial due to its illicit use, cannabis is becoming increasingly popular for its potential therapeutic value. This includes things like pain relief or assisting cancer patients reduce wasting from chemotherapy treatments, but also includes a range of potential psychological benefits for people dealing with things like stress and anxiety. As such, the authors note that the results of this study were a bit of surprise.

“We know that cannabinoid signaling plays a role in modulating stress, which is why some people use cannabis to reduce anxiety and relax,” said the first author on the paper Yoko Nomura, a Professor of Psychology at CUNY Graduate Center and Queens College in the press release announcing the study’s results. “But our study shows that in utero exposure to cannabis has the opposite effect on children, causing them to have increased levels of anxiety, aggression, and hyperactivity compared to other children who were not exposed to cannabis during pregnancy.”


In the actual study, a team from the Icahn School of Medicine at Mount Sinai and the City University of New York followed 322 mother-child pairs starting in 2009. When the children reached six years of age, the researchers used hair samples to measure their hormone levels. The research team also used electrocardiogram recordings of the children’s hearts during stress-inducing activities. This information was combined with behavior and emotional functioning surveys administered by the children’s parents to create an overall behavior map for each child.

As the press release announcing the results states, “the children of mothers who used cannabis during pregnancy showed higher anxiety, aggression, hyperactivity, and levels of the stress hormone cortisol, compared to children of non-cannabis users.”

Researchers further determined that “maternal cannabis use was also associated with a reduction in the high-frequency component of heart rate variability—the change in time interval between heart beats—which normally reflects increased stress sensitivity.”

Bottom line, the children of cannabis smoking mothers showed increased stress and anxiety markers both hormonally, behaviorally, and via heartbeat analysis.


In the study’s conclusion, the author’s note that better education in this area is critical going forward.

“Pregnant women are being bombarded with misinformation that cannabis is of no risk, while the reality is that cannabis is more potent today than it was even a few years ago,” said the paper’s senior author Yasmin Hurd, PhD, who is also the Ward-Coleman Chair of Translational Neuroscience and the Director of the Addiction Institute at Mount Sinai. “Our findings indicate that using it during pregnancy can have long-term impact on children.”

“The study results underscore the need for nonbiased education and outreach to the public and particular vulnerable populations of pregnant women regarding the potential impact of cannabis use,” added Hurd. “Disseminating this data and accurate information is essential to improving the health of women and their children.”

Follow and connect with author Christopher Plain on Twitter: @plain_fiction