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Justine Renard

Justine Renard

Research & Policy Analyst, Canadian Centre on Substance Use and Addiction

Shea Wood

Shea Wood

Knowledge Broker, Canadian Centre on Substance Use and Addiction

Despite its reputation as being harmless, the negative effects of cannabis can be passed on to your baby during pregnancy and breastfeeding.

Cannabis use in Canada is quite common. It’s been legal to use recreationally since 2018 and it’s sometimes viewed as a risk-free substance.

“There has been an increasing belief that cannabis is harmless and can relieve some of the symptoms of pregnancy — like morning sickness, nausea, anxiety, and sleep disorders,” says Justine Renard, Research and Policy Analyst at the Canadian Centre on Substance Use and Addiction (CCSA), a non-governmental organization aiming to provide national leadership on substance use. “And with this new wave of consuming organic and natural products, some pregnant women think that because cannabis is natural, it won’t harm the fetus.”

However, evidence points otherwise. More research, clinical studies, awareness, and education are needed about the effects that cannabis use can have on pregnancy, breastfeeding and infant development.


Refuting cannabis’ “miracle cure” reputation

Research compiled by the CCSA’s research team highlights the physical and mental effects that cannabis can have on babies when in utero or being breastfed.

“We found that frequent cannabis use during pregnancy is associated with low birth weight and a cluster of other risk factors related to adverse birth outcomes such as pre-term labour,” says Renard. “We also found that there are long-term effects on kids’ behaviours, including attention deficit, emotional disturbance, increased hyperactivity and impulsivity, sleep disorders, and increased risk of developing a substance use disorder later in life. There’s also some evidence of increased psychotic symptoms, anxiety, and depression. Some research shows an association between prenatal cannabis use and congenital abnormalities and autism, but those relationships still need to be confirmed with further research.”

While the research isn’t conclusive and the conclusions may be compounded by other maternal risk factors, Renard notes that cannabinoids — especially THC, the primary psychoactive component of cannabis — are lipophilic, meaning they can be stored in fat tissue and that they’re capable of passing not only through the placenta but also breast milk. As such, current research suggests that no amount of cannabis use is safe during pregnancy and breastfeeding.

Advocating for Canadians’ safety

The CCSA’s goal is to continue research in this space and to advocate for Canadians’ safety. “The CCSA is Canada’s only agency with a legislated national mandate to reduce the harms of alcohol and other drugs on Canadians, and was created by an Act of Parliament to provide national leadership to address substance use in Canada,” says Shea Wood, Knowledge Broker at the CCSA. “Staying evidence-based and making sure to get the most up-to-date evidence out to the public to help people make informed choices about their health is very important to us.”

As an independent, neutral, non-partisan, and trusted third-party expert, the CCSA collaborates with Canadian scientists and service providers to help advance its work. It also works with governments across the political spectrum to advance initiatives that reduce harm, improve wellness, and increase community safety across Canada.

If you’re pregnant or planning on conceiving, talk to your health care provider to learn about the effects of cannabis use during pregnancy and breastfeeding and to explore options for harm reduction.

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