Should You Try Weed to Soothe Your Pregnancy Woes?

A recent study shows a slight uptick in people using pot during pregnancy to ease symptoms like morning sickness. But comprehensive research is still hazy

A hand with manicured nails holds a joint

(Photo: iStock)

Ashley is nearing the end of her pregnancy, and *finally* feeling a bit more comfortable. In her first trimester, the 29-year-old chef from Saint John, N.B., felt like she’d been put in a different body. She was anxious, nauseated and—worst of all for someone who cooks for a living—she suddenly had no appetite. Instead, she started grazing like a college student, subsisting mostly on nuts, berries, and cheese and crackers.

“I really just wish I could smoke a joint right now,” she told me one day over tea. She wanted some relief from her symptoms and felt weed would help, but she wasn’t sure how safe it would be.

There are plenty of expectant parents like Ashley who are wondering whether it’s OK during pregnancy to use cannabis—or products containing its components, like cannabidiol (a.k.a., CBD, a non-psychoactive or less psychoactive element of cannabis) or Tetrahydrocannabinol (THC, the primary psychoactive constituent of cannabis). And others are already experimenting with it to combat some of the less glowy symptoms of pregnancy.

The Society of Obstetricians and Gynaecologists of Canada warns against using cannabis while pregnant. Dr. George Carson, a Regina-based OBGYN, is the former president of SOGC, and he too stands by this warning: “It is undesirable to use cannabis during pregnancy,” he says. “THC has an adverse effect on brain development, and in pregnancy, you’re growing a brain.”

Despite this widely held viewpoint within the medical community, using weed during pregnancy (mostly in the later stages) is becoming an  increasingly common practice in the United States.

In fact, according to a major study recently published in the Journal of the American Medical Association, about one in 14 pregnant women in California now uses pot during pregnancy. The study tracked almost 280,000 women over an eight-year period, and found the number using cannabis while pregnant is on the rise across all age groups. The biggest reported jump was among women aged 18-24 (a 19-percent spike since 2009), but people 35 and over are using it too—albeit reporting a more modest 3.3-percent increase.

Other retroactive studies, involving people who have already given birth but used weed during their pregnancies, have found that cannabis can help soothe morning sickness. In Maryland, it seems like these effects are being acknowledged: midwives can now prescribe cannabis to their pregnant patients.

But ultimately, there’s no conclusive proof whether smoking or consuming weed will or won’t harm a growing fetus—and that’s contributing to a lot of misinformation about pot and pregnancy.

What we think we know

The predominant line of thought in medicine is that it’s a good idea to avoid pot while pregnant. Canadian midwives are saying they don’t plan to prescribe it, even as the plant gains traction as a medicine.

“I would recommend complete abstinence,” says Alix Bacon, president of the Midwives Association of B.C. She explains that cannabis can have an impact on a child’s executive functioning—a.k.a. the part of the brain responsible for making decisions and thinking through consequences.

“What we see is impulsivity, attention deficit and hyperactivity on the behavioural side of things, and then on the neurological side of things, we see impaired visual problem solving, so like trouble with a jigsaw puzzle would be an example,” says Bacon. None of these effects tend to present right away; rather, they may take at least four years to appear. Problems might also arise with visual reasoning and short-term memory. In fact, she says, children who are exposed to cannabis in the womb may end up using a different part of their brain for some of these tasks than those who are not exposed. This holds true no matter how the cannabis is consumed—whether it’s smoked, vaped or ingested.

And while there is little evidence that cannabis can contribute to preterm birth, miscarriage or physical disability, a recent study from researchers in London, Ont. shows that that babies who were exposed to it in utero may be almost three times more likely to have lower birth weight, compared to infants not exposed to it.

MacKenzie Macht, a midwife who works at a downtown Toronto hospital, estimates that about 10 percent of pregnant people who visited that hospital used pot. She also laments that it’s hard to study the exact effects of cannabis, since results are often influenced by other factors such as whether cigarettes and alcohol were also consumed or if the person carrying the baby was self-medicating for anxiety or other issues not related to their pregnancy. Further complicating the issue: the cannabis used in these situations isn’t standardized for strength or quantity. She recommends talking to a mental health professional if you plan on using cannabis for anxiety during pregnancy.

When it comes to oils, bath soaks and balms, Bacon says there isn’t any research to draw on regarding their use while pregnant, and that it may take about 10 years to produce a reliable study on topicals.

Why people may use pot regardless of recent studies

While using pot during pregnancy isn’t recommended by Canadian medical experts, obviously some people do.

Christina, a mother of two in Toronto, is one of them. She’s pregnant for the third time. Between this pregnancy and the last, she hurt her back and used cannabis medicinally so that she could sleep through the pain. When she found out she was pregnant again, she stopped smoking. But her back pain came roaring back, along with morning sickness, so she started researching alternative forms of relief. She found a very small study involving 44 mothers in a rural southeastern community in Jamaica, 24 of whom consumed ganja tea made by steeping dried cannabis leaves in hot water, and 20 who did not. It followed the babies for one month after their birth and found none of the negative effects referred to in other studies during this time. Interestingly enough, the study also noted that one-month-old babies who had been exposed to cannabis in the womb scored higher on reflex tests and irritability tests (meaning they were less irritable). She’s been drinking it sparingly since week 8 of her pregnancy.

“I’m only taking cannabis tea once every few weeks so I don’t know how big of an impact it’s had, but when I do use it I can usually go a few days without getting sick and I feel less nauseated and less pain overall,” she says. “I think it gives my muscles a chance to relax, which helps a lot.”

Ramona, also from Toronto, smoked pot throughout her first pregnancy. Just before finding out she was pregnant, she remembers receiving news that she was HIV-positive. In order to avoid passing HIV to her child, she took medication to prevent its transmission. Nausea was a side effect of the anti-transmission meds—to the point that she constantly felt sick.

“It was horrific,” she says. “And because you’re pregnant, your senses are so heightened.” She smoked pot regularly before pregnancy, and it seemed like a natural choice to her to treat her constantly upset stomach. “As I progressed with the meds, I used it for my symptoms, and as a stress reliever,” she says.

Fast-forward 13 years, and she describes her son as having some of the high energy that studies suggest may be typical of people exposed to pot in utero, but she believes there are a number of other factors that could have contributed to that beyond pot, including her stress while pregnant and her own attention deficit hyperactivity disorder.

Caroline Meyer, a Toronto-based naturopathic doctor and reiki master, sees many people like Christina and Ramona, who complain of such severe nausea and vomiting that they end up using cannabis products “in desperation.” Meyer says this often happens after trying a series of other medical and natural remedies, but to no avail.

She estimates that about one in 10 of her pregnant patients use pot—that includes long-term smokers and those who only started using it during pregnancy for medicinal reasons. For these people, she says, “Minimal cannabis use could be a reasonable last resort to maintain their basic nutrition.”

While it may be helpful for folks who experience nausea, Meyer stresses that she would never prescribe cannabis for any pregnancy complications, and when her patients do decide to use it, it’s of their own accord and not by her suggestion. She maintains that “the safest dose is zero” during this time. She also recommends that those who used pot prior to pregnancy stop doing so—or at the very least, use it less often.

Meyer suggests natural alternatives like acupuncture to help these patients, and sometimes she also refers them to their family doctor for pharmaceutical mood support. “For women who are chronic users, pregnancy can be a great motivator to change addictive habits and find natural alternatives to help deal with the reasons they have been using long-term,” she says.

Dr. Carson in Regina says it also can be useful to try to be aware of the sorts of foods and smells that may trigger nausea and steer clear of them, if possible. He recommends eating several small meals throughout the day instead of a few larger ones, and starting off with something on the blander side because it tends to be easier on the stomach. Carson shares the same concerns as Bacon about studies suggesting cannabis can alter executive functioning.

“Whether for nausea, which it will help with, or for recreational reasons, the evidence about long-term adverse effects [of cannabis] on the brain is important,” he says. “If you’re thinking of using it as a drug, there are better alternatives.”

He refers specifically to more clinical methods for treating morning sickness, such as the brand-name drug Diclectin, the only Health Canada-approved medication to ease vomiting and nausea in pregnancy. The drug is a combination of doxylamine (an antihistamine) and pyridoxine (a form of vitamin B6) in a delayed-release formulation. While products of this sort have been deemed safe for use on the Canadian market since 1957, some doubts were raised recently by Dr. Nav Persaud, a family doctor practicing in Toronto. He had questions about bias and said there was a chunk of data missing from one of the 40-year-old studies that played a part in the drug’s approval; he decided to publish his argument in online journal PLOS One. The Society of Obstetricians and Gynaecologists of Canada responded by issuing a note to reassure expectant parents that the report did not relate to patient safety or “contradict any of the many studies showing efficacy of Diclectin.” The report did not bring forward any new information, according to the statement.

Some people take issue with pharmaceuticals nonetheless, and those feelings can be enhanced during pregnancy out of concern for the developing fetus. Macht acknowledges this. “I realize the politics of saying ‘Don’t smoke this equally accessible street drug and instead pay $100 per month to big pharma so you don’t have to feel like you have to barf every two minutes,’ but we don’t think Diclectin has the same inhibiting effects on a baby.”

Some medical professionals may consider a harm-reduction approach

While most healthcare practitioners don’t recommend using pot in any form while pregnant, Bacon says she hopes they can at least adopt a harm-reduction approach. She acknowledges that some expectant parents will use cannabis regardless of the cautions against it—but she wants those people to know that there are different ways to use cannabis, and some are more dangerous than others. For example, people who smoke cannabis can end up with up to five times the amount of carbon monoxide in their bloodstream (which can affect the level of oxygen reaching the fetus) compared to tobacco smokers. And because smoking has been shown to be associated with low birth weight, Bacon says that if you absolutely feel like you must use cannabis, it would be better to try other potentially less-harmful methods like vaping, topicals or edibles.

Meyer also takes a harm-reduction approach, telling her clients that if they’re going to use pot, to use it with the lowest frequency and dose possible. Macht says that while the level of potential harm done has not been studied on a per-trimester basis, it’s probably the most important to avoid it during the first 12 weeks. She says she knows people who use weed brownies to soothe themselves during the sometimes agonizing lead-up to labour—and she’s not convinced it would has the same effect as eating them during the first trimester might.

“The week before you go into labour, you’re dripping fluid out of your vagina all the time, you’re cramping every eight minutes,” she says. “People get so scared in this time, so some folks will have a glass of red wine every night before they go into labour, some folks will walk around, and some folks will take pot brownies.”

The quality of studies is changing—and so too how we view pot

Legalization in Canada is slated for July 1, and as it draws closer, one thing that is likely to change is the quality of study that can be done on cannabis and pregnancy, says Macht. We’re already seeing more thorough, comprehensive studies in Colorado, where it’s been legal to use cannabis for five years. Upon legalization, strains will be easier to standardize, improving consistency in studies. And as stigma falls away, perhaps more people will feel encouraged enough to report, or even participate in studies.

In the meantime, Macht and her colleagues are strongly recommending complete abstinence during pregnancy (and later, if breastfeeding, as THC can be passed through breast milk). “There’s such a culture of telling pregnant people what to do, which I loathe. but there’s good research on this particular thing,” she says. “I wish I could say if you vape it, it’s different. But the bottom line is, it’s not. This model could be crap, but this is what we’re working with right now.”

Because of this uncertainty, my friend Ashley decided to forego the joint, at least this time around. If she decides to get pregnant again, and there are better studies, it may be a different story.

As for Ramona, she doesn’t like to think about what would have happened had she not used cannabis during her pregnancy. And Christina feels content to keep sipping her tea—she just wishes it wasn’t steeped in as much uncertainty.