More and more people are using marijuana before or during pregnancy to ease nausea, pain, stress and help with sleep. In fact, research found that use has more than doubled in the last two decades.
Marijuana use in pregnancy has been linked to such adverse outcomes for the baby as lower birthweight, preterm birth and higher admission rates to neonatal intensive care units.
What about the potential danger to the mother if she uses cannabis before or during early pregnancy? According to a new study, the news there is alarming as well. There鈥檚 an increased risk of serious, potentially life-threatening maternal complications such as gestational hypertension and preeclampsia, which are both disorders of high blood pressure.
鈥淧regnant individuals who used versus did not use cannabis during early pregnancy had a 17 per cent greater risk of gestational hypertension (and) an 8 per cent greater risk of preeclampsia,鈥 said lead study author Kelly Young-Wolff, a research scientist at Kaiser Permanente Division of Research in Pleasanton, California.
People who used marijuana in early pregnancy also had a 鈥19 per cent greater risk of placental abruption,鈥 Young-Wolff said.
In placental abruption, the organ that provides oxygen and nutrients to the fetus, called the placenta, suddenly detaches from the side of the uterus, thus endangering the health of the mother and the developing baby. A detached placenta is one of the leading causes of death in both expectant mothers and babies.
鈥淩esearch suggests that pregnant people are bombarded with inaccurate messages from social media, cannabis retailers and peers suggesting that cannabis use during pregnancy is safe,鈥 Young-Wolff said. 鈥淥ur study provides timely and important data that adds to the growing body of evidence indicating that cannabis use during pregnancy is not safe.鈥
Compared to weight gain considered optimal for a successful pregnancy, people who used marijuana before or during early pregnancy were more 9 per cent more likely to gain too much weight and 5 per cent more likely to not gain enough weight during their pregnancies, the study found.
鈥淭o my knowledge, this is the largest study to date looking at cannabis use in pregnancy and adverse health outcomes in the mother,鈥 said Brianna Moore, an assistant professor at the Colorado School of Public Health in Aurora, Colorado, in an email. Moore, who studies the use of cannabis in pregnancy, was not involved in the new research.
鈥淚t is never too late to cut back or limit your use of cannabis in pregnancy to minimize the potential health effects,鈥 Moore said. 鈥淭alk to your healthcare provider.鈥
Gestational hypertension is diagnosed when an expectant mother鈥檚 blood pressure rises above 140/90 after the first 20 weeks of pregnancy, typically receding back to normal after birth. Consistent high blood pressure during pregnancy can 鈥渉inder blood flow in many different organ systems in the expectant mother including the liver, kidneys, brain, uterus, and placenta,鈥 according to the Children鈥檚 Hospital of Philadelphia.
For some women, gestational hypertension can develop into preeclampsia, a more serious form of high blood pressure in which increased blood levels of liver enzymes and protein in the urine are signs of possible kidney or liver damage in the mother. Blood platelet levels can decrease, and fluid can build up in the lungs, causing shortness of breath, according to the Mayo Clinic.
In extreme cases, such high blood pressure can lead to blood clots, seizures, stroke, temporary kidney failure and liver complications, according to the Cleveland Clinic.
鈥淧reeclampsia can also lead to preterm delivery and admission in the neonatal intensive care unit, which separates the mom and baby at the time of birth and can interfere with that initial ability to bond skin-to-skin,鈥 said OB/Gyn Dr. Deborah Ansley, medical director for the Kaiser Early Start prenatal health program in Northern California, in an email. She was not involved with the study.
How does marijuana cause such serious consequences during pregnancy? Experts believe that cannabinoids, including tetrahydrocannabinol, or THC, may bind to receptors in the placenta, disrupting estrogen signaling and affecting placental development and function.
THC is the part of the cannabis plant that creates euphoria, but more than 100 other cannabinoids have been identified in the cannabis plant, along with more than 500 other chemical substances.
The study, published Monday in the journal JAMA Internal Medicine, used health data from Kaiser Permanente Northern California, which provides health care to 4.6 million people. More than 250,000 pregnant people were asked about their marijuana use when they entered into prenatal care at approximately 8 to 10 week鈥檚 gestation. Many of those patients also underwent urine analysis that could detect any marijuana use for the past 30 days.
More than 20,000 were identified as cannabis users 鈥 including nearly 11,000 expectant mothers who did not admit to marijuana use but tested positive by urinalysis.
鈥淥ur study was unique in that we had a large enough sample size to conduct a sensitivity analysis that limited the sample to pregnant patients who did not screen positive for any other substances,鈥 Young-Wolff said.
鈥淚mportantly, results from this analysis followed the same general pattern as the main findings, indicating that our findings were not attributable to the use of other substances during pregnancy,鈥 she said.
The likelihood of developing gestational hypertension rose with the frequency of use, with daily users having the most risk.
鈥淥ur prior work has shown that the frequency of prenatal cannabis use is increasing over time, with a greater proportion of those who use cannabis during pregnancy reporting daily use in recent years,鈥 Young-Wolff said.
That鈥檚 especially worrisome as the potency of marijuana today is much greater than in the recent past, experts say.
Using at least once a month or more was linked to a greater risk of placental abruption, the study found. In addition, there was an increased risk of eclampsia, a more serious form of preeclampsia that can lead to seizures and death, but the risk was not statistically significant, according to the study.
There was one unusual finding: a reduced risk for gestational diabetes. Studies in non-pregnant adults have been mixed about the impact of marijuana on insulin resistance and metabolic syndrome, a mix of health issues that can lead to diabetes and other chronic diseases, Moore said.
鈥淢ore studies are needed to understand whether and how cannabis use in pregnancy may impact risk for gestational diabetes,鈥 Moore said.
The study has limitations, the authors acknowledge. For one, they were not able to determine if marijuana use continued during the pregnancy.
鈥淢y suspicion is that the health effects would be stronger if the pregnant person continued to use cannabis after the first trimester, but more studies are needed,鈥 Moore said.
Urine tests could only look for THC and no other cannabinoids, and the self-report could not determine if use was due to smoking or edibles, Young-Wolff said. In addition, since all of the expectant mothers were based in northern California, a state which legalized medicinal cannabis in 1996 and adult use sales in 2018, the results may not be generalizable to other populations in the United States.
The results may also not be applicable to the general population since 鈥渢he participants in this study were older, had higher incomes, and almost all had private health insurance,鈥 Moore added.
As the known health risks for marijuana grow, pregnant women should feel free to discuss any cannabis use with their health care provider without fear of reprisal, experts say.
鈥淚f pregnant individuals are considering using cannabis during pregnancy to self-medicate pregnancy-related symptoms, we encourage them to discuss those symptoms with their doctor and use interventions recommended by clinical practice guidelines,鈥 Young-Wolff said. 鈥淚f pregnant individuals are not willing to quit using cannabis, we recommend that they try to use it less frequently.鈥
Conservative Leader Pierre Poilievre and NDP Leader Jagmeet Singh got into a heated exchange in the House of Commons on Thursday, just minutes after Singh announced his party would not be supporting the Conservatives' first non-confidence motion against Prime Minister Justin Trudeau's government.
The province's public security minister said he was "shocked" Thursday amid reports that a body believed to be that of a 14-year-old boy was found this week near a Hells Angels hideout near Quebec City.
Shamattawa RCMP are searching for a missing six-year-old boy who hasn鈥檛 been seen since Wednesday morning.
B.C.'s police watchdog is investigating the death of a woman who was shot by the RCMP after allegedly barricading herself in a room with a toddler early Thursday morning.
Prime Minister Justin Trudeau tapped Treasury Board President Anita Anand to take on additional duties as Canada's minister of transport on Thursday.
CTV News has learned there are multiple Canadian women alleging they were victims of sexual abuse at the hands of the late Harrods boss Mohamed Al Fayed.
The Royal Canadian Mounted Police has lost 205 firearms since 2020, including more than 120 handguns and at least five fully automatic weapons like machine-guns.
Shohei Ohtani became the first major league player to hit 50 home runs and steal 50 bases in a season, with the Los Angeles Dodgers star going deep twice to reach the half-century mark and swiping two bags to get to 51 against the Miami Marlins on Thursday.
Quebec Premier Francois Legault is calling on the Bloc Quebecois to topple the Trudeau government next Wednesday and trigger a federal election.
B.C.'s police watchdog is investigating the death of a woman who was shot by the RCMP after allegedly barricading herself in a room with a toddler early Thursday morning.
Shamattawa RCMP are searching for a missing six-year-old boy who hasn鈥檛 been seen since Wednesday morning.
Friends and strangers have set up a makeshift memorial outside the home of a five-year-old boy who was found dead yesterday in Coteau-du-lac.
The Royal Canadian Mounted Police has lost 205 firearms since 2020, including more than 120 handguns and at least five fully automatic weapons like machine-guns.
The lawyer for a B.C. RCMP officer convicted of obstruction for telling a witness to delete cellphone video following the violent 2017 arrest of Dale Culver has requested a stay of proceedings.
The province's public security minister said he was "shocked" Thursday amid reports that a body believed to be that of a 14-year-old boy was found this week near a Hells Angels hideout near Quebec City.
A federal law enforcement agency confirmed it's opened an investigation into Robert F. Kennedy Jr. after he allegedly cut off the head of a dead whale and took it home two decades ago.
A judge in a rural Kentucky county was shot and killed in his courthouse chambers Thursday, and the local sheriff was charged with murder, police said.
Israel warned U.S. Defence Secretary Lloyd Austin in a call Tuesday that a military operation was going to take place in Lebanon but gave no details, U.S. officials said Thursday. The same day of the call, in an attack widely blamed on Israel, thousands of pagers belonging to Hezbollah militants exploded.
A 22-year-old woman who became an abortion rights advocate after she was raped by her stepfather as a child tells her story in a new campaign ad for Democratic presidential nominee Kamala Harris.
South Korea鈥檚 government, western countries and adoption agencies worked in tandem to supply some 200,000 Korean children to parents overseas, despite years of evidence they were being procured through questionable or downright unscrupulous means, an investigation led by The Associated Press found.
Israeli security services said on Thursday they had arrested an Israeli citizen on suspicion of involvement in an Iranian-backed assassination plot targeting prominent people including Prime Minister Benjamin Netanyahu.
The head of Via Rail repeatedly told MPs a train delay over the Labour Day long weekend was an isolated incident, despite a similar event two years ago.
Conservative Leader Pierre Poilievre and NDP Leader Jagmeet Singh got into a heated exchange in the House of Commons on Thursday, just minutes after Singh announced his party would not be supporting the Conservatives' first non-confidence motion against Prime Minister Justin Trudeau's government.
Prime Minister Justin Trudeau tapped Treasury Board President Anita Anand to take on additional duties as Canada's minister of transport on Thursday.
Ontario鈥檚 Minister of Sport, Neil Lumsden, will donate his brain to research.
Manitobans are getting another reminder of how long wait times are for diagnostic images.
A new strain of the virus is spreading, largely through skin-to-skin contact, including but not limited to sex. A lack of funds, vaccines and information is making it difficult to stem the spread, according to alarmed disease experts.
Thanks to a special Texas law, NASA's Butch Wilmore and Suni Williams, the two veteran astronauts, will still be able to perform their civic duty, voting absentee from low-Earth orbit for the U.S. election in November.
Lebanese authorities on Thursday banned walkie-talkies and pagers from being taken on flights from Beirut airport, the National News Agency reported, after thousands of such devices exploded during a deadly attack on Hezbollah this week.
NASA scientists have successfully replicated spider-like shapes found on the surface of Mars in a laboratory setting for the first time.
Lawyers representing the producers of 'Russians at War' say they may pursue legal action against Ontario's public broadcaster for pulling support for the controversial documentary amid outcry from the Ukrainian community and some Canadian politicians.
Viewers of Jeopardy got a chance to test their knowledge of trivia about B.C.'s biggest city Wednesday night.
British actress Florence Pugh has revealed that shaving her head for her latest movie role was a 'really bizarre' experience that sent her body 'into a bit of trauma.'
A case involving stolen funds from a Saskatchewan business being used to purchase cryptocurrency will be heading back to the courts, thanks to a new decision by Saskatchewan's Court of Appeal.
Nike Inc. said Thursday it has named Elliott Hill as its president and CEO, replacing John Donahoe, who will retire next month.
Maple Leaf Foods asserted its innocence in an alleged bread price-fixing scheme ahead of a hearing to determine whether it will be added to an ongoing class-action lawsuit.
Only one Toronto restaurant earned a Michelin star this year, but it is not a first for the chef who brought the establishment to stardom.
They say a dog is a man鈥檚 best friend. In the case of Darren Cropper, from Bonfield, Ont., his three-year-old Siberian husky and golden retriever mix named Bear literally saved his life.
For most people, dinner on a cruise ship is a time to relax. But when influencer couple Abby and Matt Howard decided to kick back with a dinner 脿 deux, they ended up kicking up a storm.
Shohei Ohtani became the first major league player to hit 50 home runs and steal 50 bases in a season, with the Los Angeles Dodgers star going deep twice to reach the half-century mark and swiping two bags to get to 51 against the Miami Marlins on Thursday.
Vancouver Canucks goalie Thatcher Demko says he's been working his way back from a rare lower-body muscle injury since being sidelined in last season's playoffs.
Toronto Blue Jays shortstop Bo Bichette returned to the 10-day injured list Thursday due to a right middle finger fracture.
Video of a brazen daylight auto theft which shows a suspect running over a victim in a stolen luxury SUV has been released by police west of Toronto.
The plant was expected to produce batteries for a million electric vehicles a year. Once up and running, it was supposed to create hundreds of permanent jobs in a small southeastern Ontario municipality. But two years later, spending on the construction of the Umicore plant has been delayed in what the company calls a "significant worsening of the EV market context."
A Winnipeg man is asking for help after a classic car that has been a part of his family since the 1950s was stolen from his garage.
They say a dog is a man鈥檚 best friend. In the case of Darren Cropper, from Bonfield, Ont., his three-year-old Siberian husky and golden retriever mix named Bear literally saved his life.
Paleontologists from the Royal B.C. Museum have uncovered "a trove of extraordinary fossils" high in the mountains of northern B.C., the museum announced Thursday.
The search for a missing ancient 28-year-old chocolate donkey ended with a tragic discovery Wednesday.
The Royal Canadian Mounted Police is celebrating an important milestone in the organization's history: 50 years since the first women joined the force.
It's been a whirlwind of joyful events for a northern Ontario couple who just welcomed a baby into their family and won the $70 million Lotto Max jackpot last month.
A Good Samaritan in New Brunswick has replaced a man's stolen bottle cart so he can continue to collect cans and bottles in his Moncton neighbourhood.
David Krumholtz, known for roles like Bernard the Elf in The Santa Clause and physicist Isidor Rabi in Oppenheimer, has spent the latter part of his summer filming horror flick Altar in Winnipeg. He says Winnipeg is the most movie-savvy town he's ever been in.
Edmontonians can count themselves lucky to ever see one tiger salamander, let alone the thousands one local woman says recently descended on her childhood home.
A daytrip to the backcountry turned into a frightening experience for a Vancouver couple this weekend.
B.C.'s police watchdog is investigating the death of a woman who was shot by the RCMP after allegedly barricading herself in a room with a toddler early Thursday morning.
Since she was a young girl growing up in Vancouver, Ginny Lam says her mom Yat Hei Law made it very clear she favoured her son William, because he was her male heir.
The 'Namgis First Nation says a fish farm it owns near Port McNeill shows the potential of land-based aquaculture in B.C.
Toronto police are asking for the public's help in identifying one of the suspected shooters in Tuesday's fatal double shooting in North York.
A pedestrian has been seriously injured after being struck by a vehicle in North York.
Students across York Region will once again see uniformed officers at school, however police and board officials say they will only be stopping by for the occasional safety presentation.
We've produced a special webcast edition of CTV News Calgary for Thursday, Sept. 19, 2024.
The Parole Board of Canada says a man who assaulted a young pregnant woman and left her for dead remains too dangerous to be released into the community.
A Vulcan, Alta., man has been charged with a Lethbridge woman's murder after her body was found in the Oyen area.
Police say a man who was taken to hospital in critical condition after being shot Thursday night has died.
A byelection was called for the Bay of Quinte riding less than a week after Progressive Conservative MPP Todd Smith, Ontario's education minister at the time, resigned his seat in August.
Customers are in the dark about the sudden closure of the Upper Room Furniture stores. The company has filed papers under the Bankruptcy and Insolvency Act. It鈥檚 not known whether orders placed and paid for will be honoured.
Quebec Premier Francois Legault is calling on the Bloc Quebecois to topple the Trudeau government next Wednesday and trigger a federal election.
A harrowing video has been presented to a jury at the trial of three men facing first-degree murder charges.
The province's public security minister said he was "shocked" Thursday amid reports that a body believed to be that of a 14-year-old boy was found this week near a Hells Angels hideout near Quebec City.
Five bison are dead at Elk Island National Park east of Edmonton following an early Thursday morning collision.
An Edmonton man who is charged with sexually assaulting a teen boy is a member of the Alberta sheriffs, CTV News Edmonton has confirmed.
The mayor of Fort Saskatchewan apologized on Thursday for comments she made earlier this week about killing feral cats.
New Brunswick Premier Blaine Higgs has called for a provincial election. Voters will go to the polls on Oct. 21, as prescribed by the province's fixed-date election law.
Police are asking people to avoid the Dartmouth Commons area in Dartmouth, N.S., as they assist with a wildlife call for a bear.
An 83-year-old man is facing sexual interference charges following a Nova Scotia RCMP investigation.
Manitobans are continuing to mop up after a deluge of rain hit southern Manitoba earlier in the week.
Shamattawa RCMP are searching for a missing six-year-old boy who hasn鈥檛 been seen since Wednesday morning.
A Winnipeg pet rescue is putting out a warning to dog owners across the city about a possible parvovirus in the province.
A social media post of purple apples 鈥済rowing鈥 in Saskatchewan has sparked a lot of attention. However, garden experts say there's no such thing.
A case involving stolen funds from a Saskatchewan business being used to purchase cryptocurrency will be heading back to the courts, thanks to a new decision by Saskatchewan's Court of Appeal.
Environment and Climate Change Canada (ECCC) has confirmed a tornado touched down Wednesday evening near Langbank, Sask.
Amber and Adam Brueckner have a pool-shaped hole in their backyard 鈥 and their wallets.
New details have been shared about a missing family that was last seen on Sept. 1 in Kitchener, Ont.
Police are trying to identify a man who approached a woman and child in Wellesley.
A gym teacher at a private Christian school in Saskatoon has been charged. Terra MacEwan, 44, is charged with assault with a weapon. A Saskatoon mother who spoke with CTV News says her autistic son was MacEwan's victim.
Thomas Hamp says he believed secret police were out to kidnap, torture, and kill him when he fatally stabbed his girlfriend Emily Sanche in February of 2022.
A social media post of purple apples 鈥済rowing鈥 in Saskatchewan has sparked a lot of attention. However, garden experts say there's no such thing.
They say a dog is a man鈥檚 best friend. In the case of Darren Cropper, from Bonfield, Ont., his three-year-old Siberian husky and golden retriever mix named Bear literally saved his life.
As northern Ontario gets ready to welcome autumn this weekend, it鈥檚 still feeling a lot like summer as provincial forest fire crews continue to battle blazes.
James Bay Ontario Provincial Police have charged four commercial vehicle drivers with impaired, including one who was hauling 36,000 kilograms of ammonia hydrate.
A Woodstock homeowner says she鈥檚 at her wit鈥檚 end over a homeless encampment situated alongside her backyard. She鈥檚 calling on the city to do more to help those living rough, so she can live in peace.
Police were focusing their attention on the northeast corner of Richmond and Horton, with members of the emergency response unit taking up positions at the scene.
A union representative says someone driving a pick-up truck with heavily tinted windows rammed a member on Western Road, near Elborn College.
Two men from Barrie have been charged after a deadly shooting at a park in Keswick on Wednesday.
A growing group of brides and wedding photographers from across the province say they have been taken for tens of thousands of dollars by a Barrie, Ont. wedding photographer.
A 32-year-old man is facing charges after police say his vehicle struck a child in an Owen Sound intersection.
The Windsor Police Service (WPS) has seized over $56,000 in drugs and have arrested one suspect.
SERVEONE Canada, a global procurement solution company, has begun Canadian operations in Tecumseh.
Enrolment may be down at St. Clair College, but President Mike Silvaggi isn鈥檛 bothered.
In a rare move, the Greater Victoria School District Board of Education has been slapped with a ministerial order from the province requiring it to update a student safety plan 鈥 drawing concern around political posturing leading up to an election.
The Union of B.C. Municipalities is asking the provincial government to make transit free for teenagers.
To appreciate why Mimi Vandermolen is so pleased to notice one particular vehicle she鈥檚 walking past, you need to know that seeing this many cars in one place would have been unimaginable when she was growing-up in the post-war Netherlands.
A pair of runaway pigs are in the custody of an animal sanctuary in the Okanagan after evading police and volunteers for hours earlier this week.
The Red Bridge, a historic landmark in Kamloops, B.C., was completely destroyed by fire early Thursday morning.
Animal protection officers in British Columbia have rescued three pit bulls 鈥 including one that gave birth to 10 puppies 鈥 from a rat-infested home in Kelowna.
A Vulcan, Alta., man has been charged with a Lethbridge woman's murder after her body was found in the Oyen area.
A Lethbridge couple got a good reminder as to why you should keep your vehicle doors locked at all times.
Lethbridge residents who live near the police range can expect to hear plenty of shots fired Wednesday and Thursday.
A new community health profile in the Algoma District shows the area is significantly below provincial averages in a number of health metrics.
North Bay Police Service says one person has died following an industrial accident at the Ontario Northland Transportation Commission Rail Yard on Tuesday.
Three northern Ontario residents are charged with drug trafficking after the vehicle they were in got stuck along a bush road off Highway 17 on Monday.
Newfoundland and Labrador's chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
A 16-year-old biennial event aimed at fostering business in the country's eastern Arctic and northern regions has been cancelled indefinitely as a dispute unfolds between Inuit in Canada and a Labrador group claiming to share their heritage.
Jim Lester鈥檚 farm hopped on the cow-cuddling trend in early August, and his time slots have been pretty well sold out ever since.
The Shopping Trends team is independent of the journalists at CTV News. We may earn a commission when you use our links to shop.聽Read about us.
