More pregnant women are using cannabis, research shows, despite warnings of its danger from health officials.
According to a recent U.S. study, the number of women who use cannabis while expecting has increased, and the number of women who use cannabis in the year before pregnancy has nearly doubled.
Researchers surveyed 276,991 expectant mothers in northern California and found the number of women who said they used cannabis in the year before their pregnancy grew from 6.8 per cent in 2009 to 12.5 per cent in 2017.
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While the number of women who reported using the drug while pregnant was smaller, it still increased from 1.9 per cent to 3.4 per cent during the same time.
Among the women who reported using the drug while expecting, daily cannabis use increased from 15 per cent in 2009 to 21 per cent in 2017.
The findings, published in the medical journal JAMA Network Open, suggest that increased acceptance of cannabis use and a lack of awareness around fetal harm are factors in the uptick.
The researchers point out that evidence suggests heavier cannabis use might be “associated with worse neonatal health outcomes.”
“Despite this risk, however, U.S. data suggest that 71 per cent of pregnant women who used cannabis in the past year perceive no or slight risk in using cannabis once or twice a week,” the researchers wrote.
Another study by the U.S.’s National Institute on Drug Abuse yielded similar results.
Data collected from 467,100 pregnant women across the U.S. showed past-month cannabis use, daily cannabis use, and occurrence of cannabis use had all increased over the last 15 years.
Between 2002 to 2003 and 2016 to 2017, past-month cannabis use increased from 3.4 per cent to seven per cent among pregnant women overall.
During their first trimester, 12 per cent of women reported using the drug as of 2017, up from just under six per cent in 2003.
What are the risks of using cannabis while pregnant?
The FDA recently released a warning about women using cannabis while expecting or breastfeeding, saying that “marijuana use during pregnancy may affect fetal brain development.”
If a woman uses the drug while pregnant, THC — a cannabinoid found in cannabis — can enter the fetal brain from the mother’s bloodstream, the FDA says.
READ MORE: Cannabis during pregnancy linked to higher risk of pre-term birth
The government agency also said if a mother uses cannabis while breastfeeding, it can remain in breast milk. This exposure can affect a newborn’s brain development and “result in hyperactivity, poor cognitive function, and other long-term consequences.”
The U.S.’s National Institutes of Health also raised concern around expectant moms and cannabis.
“Cannabis use during pregnancy has been associated with effects on fetal growth, including low birth weight and length, and these outcomes may be more likely among women who consume marijuana frequently during pregnancy, especially in the first and second trimesters,” the NIH wrote.
A recent study out of the Ottawa Hospital Research Institute found that cannabis use in pregnancy was associated with “significant increases in the rate of preterm birth.”
Why are women using cannabis while pregnant?
Canadian researchers say more women are using cannabis during pregnancy because they are not informed of its risks.
Research out of the University of British Columbia found that around one-third of pregnant women think it’s safe to use cannabis while expecting and are unaware of potential health risks to their child.
The findings, published earlier this year in the journal Preventive Medicine, looked at data from six U.S. studies and found that “more women seem to be using cannabis during pregnancy than ever before, even though evidence of its safety is limited and conflicting.”
The UBC researchers found that one of the main reasons women may think cannabis is safe is because there’s not enough communication between patients and doctors when it comes to the drug.
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Bayrampour added that her findings also indicate that many women don’t consider cannabis to be a drug, or that it’s a harmful one.
Laura.Hensley@globalnews.ca