Weed in the Womb
Is cannabis safe during pregnancy is certainly a question that causes many to ponder. We know, and have known, for many years that alcohol use is strongly discouraged during pregnancy. Lots of retroactive studies have undoubtedly proven the association of alcohol use in pregnancy and developmental delays, behaviour disorders and Fetal Alcohol Spectrum Disorder.
But now that cannabis is legal to buy and use in Canada, many women are asking: Is it safe for me to smoke/vape or ingest a tasty edible during pregnancy? Seemingly harmless since it is a plant, after all, which causes many to think, “Doesn’t that mean it’s natural and therefore safe?” I mean, it must be better than smoking cigarettes or using illegal drugs, like meth and heroin. But you would be surprised at how difficult a question this is to answer.
It’s really hard to study the affects of cannabis use on mothers and their unborn babies. Although legal now, until October of last year it wasn’t, so who would ever admit that they used cannabis at a party, or to combat morning sickness or relieve anxiety when they were expecting for fear of having their children taken away by Family and Children’s Services (F&CS) and being labeled as a druggie or an addict. Even now after legalization, a strong stigma exists for those who admit cannabis use. Not many women were willing to admit they use cannabis during pregnancy, even if their use is rare, so it becomes difficult to gather a lot of data. We can’t study what we don’t know.
“If you choose to use cannabis during or throughout your pregnancy, talk to your healthcare provider. Don’t hide your use or be ashamed.”
As a nurse in a busy labour and delivery unit, I have encountered patients who have used pretty much everything. It used to be, years ago, that if a mom admitted she had smoked weed in her pregnancy we had to call F&CS. As the years have gone by, most social workers would tell you that marijuana was the least of their worries and not to bother. How things have changed. That being said, there are a few good studies, that although have limited data, the data they produced seems to hold up.
What we also know about cannabis use in pregnancy and its effects on neonates is that cannabis does cross the placenta. Meaning that if you smoke, vape or ingest it, it will eventually enter your baby’s blood stream and their body. Health Canada and the Society of Obstetricians and Gynecologists of Canada (SOGC) have released data that states cannabis effects the brain of adults and adolescents (this has been well studied). Health Canada recommends adolescents avoid cannabis use as it can affect the rapidly developing brain of a teenager and cause mental health and behaviour issues.
Theoretically, apply that same science to a rapidly growing fetal brain, producing millions of new cells a day. Use of cannabis could then affect the growth and development of a baby’s brain. The cells of the human brain are lipophilic, meaning they are made up mostly of lipids or fat. We know that THC deposits easily into fat cells and can stay there for long periods of time.
Use of cannabis has been linked to poor birth outcomes in infants. A few studies have cited low birth weight in infants of mothers who self reported cannabis use. Having a slightly smaller baby might sound somewhat appealing to some (I myself had a nine-pound baby and could have done with a wee bit smaller personally), but having a baby with low birth weight has been strongly associated with long-term health effects, such as an increased risk of respiratory issues in infancy and adulthood, increased risk of diabetes, hypertension, cardiovascular disease and long-term decreased academic achievement.
The same studies also looked deeper at the long-term consequences and noted infants whose mothers used cannabis daily at 0-3 years of age had difficulty being calmed, had exaggerated startle reflexes and notable sleep problems. At 3-6 years of age researches noted poor memory, increased impulsive behaviours and decreased ability to focus and maintain attention. Lastly at 6-10 years of age an increase in reports of hyperactivity, learning difficulties, increased incidence of depression, anxiety, difficulty with decision making and attention issues.
All that being said, what the studies also state is that most mothers in the study, used cannabis daily, also smoked cigarettes, were of lower socioeconomic status, had poor nutrition and poor physical and mental health. So, its hard to know, if these were healthy, middle-class women, who smoked or vaped occasionally, would the effects on the baby or child have been the same? What all this means really, is it’s hard to draw a final conclusion.
Should you or shouldn’t you use cannabis if you are pregnant? Could you harm your baby? We really don’t have enough solid evidence to say. Health Canada and SOGC caution women against cannabis use in pregnancy, and if they do choose to use that they decrease their use if possible.
My final advice as a nurse and childbirth educator is that more research needs to be done. We don’t definitively know if or what amount of cannabis use is safe in pregnancy. If you choose to use cannabis during or throughout your pregnancy, talk to your healthcare provider. Don’t hide your use or be ashamed. By letting your obstetrician, family doctor or midwife know, they can help you if you need assistance decreasing your use, discuss safer options for use (smoking vs. vaping) and help you decide what is best for you, your situation and your baby.
This article originally appeared in the Spring 2019 issue of The Holistic Parent.