A handful of cannabis bud is shown in Fenwick, Ont., on Tuesday, June 26, 2018. THE CANADIAN PRESS/Tijana Martin

Researchers find cannabis use in pregnancy linked to greater risk of autism

Researchers caution findings only show association — not cause and effect

A new study links cannabis use in pregnancy to a greater risk of autism.

Researchers including experts from the Ottawa Hospital and the University of Ottawa reviewed data from every birth in Ontario between 2007 and 2012, before recreational cannabis was legalized.

They found 1.4 per cent of 18-month-olds were diagnosed with autism but that rate was higher among children exposed to cannabis in the womb, at 2.2 per cent.

RELATED: New study suggests autism overdiagnosed: Canadian expert

RELATED: Surf’s Up Tofino offers wave of positivity for families living with autism

Of roughly 500,000 women in the study, 3,000 reported cannabis use during pregnancy. The analysis focused on 2,200 women who said they only used cannabis during pregnancy, and no other substances.

Researchers don’t know how much cannabis was used, how often, at what stage of their pregnancy, or how it was consumed. They also caution the findings only show association — not cause and effect.

The findings were published today in the medical journal Nature Medicine.

Even though recreational cannabis is now legal and more socially acceptable, study co-author Dr. Darine El-Chaar says that doesn’t mean it’s safe for people who are pregnant or breastfeeding.

El-Chaar says cannabis use seems to be more prevalent, with her patients much more open about telling her it helps ease their morning sickness or pain.

“Our answer is still that we don’t have correct, properly made studies that are designed to look at this question,” says El-Chaar, a maternal-fetal medicine physician and clinician investigator at the Ottawa Hospital and assistant professor at the University of Ottawa.

Researchers had previously found that cannabis use in pregnancy was linked to an increased risk of preterm birth. That study also found pregnant women who used cannabis often used other substances including tobacco, alcohol and opioids.

Funding came from the Canadian Institutes of Health Research.

— By Cassandra Szklarski in Toronto

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

West Shore Rotary Club raises $20,000 with Golf Ball Drop fundraiser

Nearly 4,000 golf balls poured onto Olympic View golf course Saturday

Construction slows weekend traffic at Millstream overpass

West Shore RCMP recommend Leigh Road exit instead

TRAFFIC: Saanich emergency crews responding to Pat Bay Highway collision

Incident took place at Haliburton Road intersection

Saanich race car driver shifts gears as pandemic cuts U.S. season short

Bill Okell, 65, sets sights on Canadian racing circuit for 2020

Chorus expands online options to in-person rehearsal in Langford, Oak Bay

Free, non-auditioned SingYourJoy recruits those aged 16 to 29

B.C. records 98 more COVID-19 cases, most in Lower Mainland

One new senior home outbreak, Surrey Memorial outbreak over

POLL: Do you agree with the decision to call a provincial election for Oct. 24?

British Columbians will put their social distancing skills to the test when… Continue reading

Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

Vancouver Island Tour de Rock riders roll into Parksville Qualicum Beach

Saturday’s schedule includes Port Alberni, Ucluelet and Tofino, followed by Nanaimo on Sunday

97 distressed horses, cats and dogs seized from farm in Princeton

RCMP assisted as BC SPCA executed search warrant

$250K reward offered as investigation continues into Sea to Sky Gondola vandalism

Police also asking for specific footage of Sea to Sky highway around time of incident

Most Read