A new study conducted in Canada found an association between marijuana use in pregnancy and increased risk of autism
Don't store avocado like this: it's dangerousThe risk of autism may be higher in babies born to women who smoked marijuana during pregnancy. That's what a new study conducted in Canada says.
Extensive research, carried out by a team from Ottawa Hospital, BORN Ontario and the University of Ottawa and recently published in the journal Nature, examined data from every birth that occurred in Ontario (Canada) between 2007 and 2012, well before recreational marijuana was legalized in the country in 2017.
It involves over 500 boys and girls, part of what is believed to be one of the largest studies of its kind.
Out of half a million women, the researchers then narrowed the study to about 2200 women and they reported using cannabis during pregnancy without mixing it with tobacco, alcohol or opioids. They were the ones who were most likely to have autistic babies born:
"Women who used cannabis during pregnancy were 1,5 times more likely to have a child with autism," said Dr. Darine El-Chaâr, maternal fetal medicine specialist, clinical researcher at the Ottawa Hospital Research Institute. and lead author of the study.
The study reports that the incidence of autism in children exposed to cannabis during pregnancy was 4 per 1000 people per year, compared with a level that stopped at 2,42 for unexposed children.
The same researchers had previously found that cannabis use in pregnancy was linked to an increased risk of preterm birth.
Marijuana has become more common in recent years, and health researchers worry that mothers-to-be may think it's okay to use it to treat, for example, morning sickness or other pregnancy-related annoyances, despite the lack of research on the long-term impacts that can have on the fetus.
Pain management, El-Chaâr said, is the most common reason for using marijuana in pregnancy.
“It helps with various conditions they may have or with nausea and vomiting in pregnancy. Some people use it to sleep or to reduce stress. Still others use it recreationally; it's just part of their routine. "
The use of marijuana by pregnant women has grown in the United States over the past few decades. An analysis last year of more than 450.000 pregnant American women between the ages of 12 and 44 by the National Institute on Drug Abuse found that cannabis use more than doubled between 2002 and 2017.
As the new study found, the vast majority of marijuana use occurred during the first three months of pregnancy. Yet the first trimester is one of the most important moments for the development of the fetus also at the brain level, when it is most susceptible to damage, said El-Chaâr.
The authors of the Canadian study acknowledged that this is a limited search. She did not detect the amount and type of marijuana women used during pregnancy, nor was she able to tell how often women used it.
The study therefore it does not prove conclusively that marijuana use during pregnancy causes autism, only that there is an association between the two factors to be investigated with subsequent research.
Fonti: The Ottawa Hospital / Nature
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