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Study Finds Depression Is the Largest Predictor of Substance Use During Pregnancy

August 22, 2019

Depression outranks education, income, and age as the single largest predictor of substance use during pregnancy, suggests a study published in the Journal of Neonatal-Perinatal Medicine.

“Pregnant women who were depressed were 2.6 times more likely to use cannabis and twice as likely to smoke cigarettes and use alcohol while pregnant,” said Jamie Seabrook, PhD, a professor at Brescia University College at Western University in Ontario, Canada. “We don’t know when the substance use first began, but we do know that it was continuing during pregnancy—and that is a big risk factor for poor maternal and infant health outcomes.”

The findings stem from a retrospective cohort study of 25,734 pregnant women in Southwestern Ontario.

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Specifically, researchers found that, compared with women who were not depressed during pregnancy, pregnant women who were depressed were 2.56 times more likely to use cannabis, 2.15 times more likely to use alcohol, and 1.70 times more likely to smoke tobacco.

The findings are especially important with the recent legalization of recreational cannabis in Canada and elsewhere, researchers pointed out, given the association between substance use during pregnancy and poor birth outcomes.

“The research shows that there is an effect later on in life as well with infants that are born preterm or low birth weight,” said Rachel Brown, an MSc candidate and first author of the study. “To intervene or advocate for mental health programs for the mom, the idea is that it sets up the health of the infants later on in life.”

“Let’s help women with their mental health to improve their overall health and, in doing so, improve the health of their baby,” Dr. Seabrook added.

—Jolynn Tumolo


Brown RA, Dakkak H, Gilliland J, Seabrook JA. Predictors of drug use during pregnancy: the relative effects of socioeconomic, demographic, and mental health risk factors. Journal of Neonatal-Perinatal Medicine. 2019;12(2):179-187.

Depression is the single largest predictor of substance use during pregnancy [press release]. Ontario, Canada: University of Western Ontario; August 8, 2019.

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