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Cannabis & Pregnancy

I’m a soon to be first time mom and I don’t know too much about the do’s and don’ts of smoking with a new addition to the household. Should I wait until he becomes older because I will be breastfeeding or do you think everything will be OK from the get go?

Thank you, CeCe from Phoenix

Kelly here again, Mama’s oldest daughter and temporary question answerer while she prepares for her big move to Portugal. I’ll be filling in while she’s gone and settling in her new home, but like Mama does, she’s still helping out so keep those questions coming. I’ll do my best to share with you some of that wisdom that Mama raised me with!

With more and more states legalizing cannabis medically and recreationally, it’s only reasonable that questions will arise regarding cannabis consumption and pregnancy. Unfortunately, the data we have is not the most reliable, and – in my opinion – is inherently flawed. Let me preface this article by saying that I am by no means a medical professional nor have I ever been pregnant, but I do think it’s important to understand what kinds of studies are being done, what claims are being made, etc. as a cannabis consuming uterus owner – and even if you’re not.

It has been proven that THC can cross the placental barrier and enter the fetal bloodstream, so it makes sense to question how this and other cannabinoids, like CBD, could affect a developing fetus, early childhood development or the health of the mother. The short answer is that we just don’t know yet.

Pregnancy and cannabis use is a complex issue. There is no official federal screening system for cannabis use during pregnancy in the US and in some states, substance use is enough to bring on child abuse or neglect inquiries. Data is hard to come by; while the legality of cannabis varies from state to state, it can be difficult to obtain reliable data. Pregnant women in prohibition states may be less likely to disclose cannabis use to their doctors or other healthcare professionals because of legal or social repercussions. Some states don’t screen for cannabis, focusing on other substances that have known adverse effects for pregnant women and developing fetuses. Women who are open with their doctors about their cannabis use may face ridicule or criminal behavior lectures, or even allegations of abuse.

In my research for this article, there was one particular study that I found cited multiple times across articles regarding pregnancy and cannabis use. In 2017, the Journal of the American Medical Association published a research letter titled “Trends in Self-reported and Biochemically Tested Marijuana Use Among Pregnant Females in California from 2009-2016” conducted at Kaiser Permanente Northern California (KPNC). KPNC screens all pregnant women at their facility for cannabis use, using a self-report survey and urine toxicology reports.

KPNC conducted the study on pregnant women aged 12 years and older, administering the self-report survey and urine toxicology test at approximately 8 to 10 weeks gestation, from 2009 to 2016. The research letter, however, does not say whether these women were screened throughout their pregnancy for cannabis use, nor did they delve into method of use, quantity, frequency or potency. Instead, the study focused on the amount of pregnant women either self-reporting or testing positive for cannabis in the first eight to ten weeks of pregnancy, their age group, racial demographic and household income. In addition, cannabis can be detected up to 30 days after consumption, which could mean that some of the women in this study had last consumed cannabis prior to becoming pregnant or prior to becoming aware of the pregnancy.

This KPNC study is cited in multiple articles related to the safety of cannabis consumption during pregnancy when it appears that the study wasn’t actually focused on that at all. In fact, there is one sentence in the whole letter related to the medical effects of cannabis during pregnancy: “Initial evidence suggests that prenatal marijuana use may impair fetal growth and neurodevelopment, but in 79% of 785 women surveyed between 2007 and 2012 reported perceiving little to no harm in prenatal use.

The study focused on the increase in cannabis use, either self-reported or discovered through toxicology, within the different age groups, finding the greatest increase among those 18-24. It doesn’t take a study to know that the national attitude towards cannabis has significantly shifted in the last ten years, and I believe this is what is reflected in the study. Not to mention the fact that Kaiser Permanente Northern California is just that, a medical facility in Northern California that has had legalized medical cannabis since 1996.

What’s frustrating is that the articles citing the KPNC study are geared toward the safety of cannabis consumption, and overwhelmingly suggest that it’s unsafe. Kelly Young-Wolff, one of the KPNC researchers involved in the study, is quoted in an article saying “no amount of cannabis has been shown to be safe during pregnancy,” but the science on both sides is limited, and often incomplete or outdated.

Most studies I found focus solely on smoking as the means of consumption. The National Academies of Sciences, Engineering and Medicine published a report on cannabis that reviewed more than 10,000 studies published between 1999 and 2016 and focused on smoking as the primary means of consumption. The report found that cannabis “shows promise” for treating chronic pain and multiple sclerosis, but also suggests that prenatal use of cannabis may contribute to lower birth weight. Marie Claire McCormick, professor of maternal and child health at Harvard and chair of the National Academy of Sciences that released the report, says that they couldn’t determine whether it “is a direct effect of marijuana or smoking” and that birth weight findings were consistent with the effects of cigarette smoking. Smoking increases carbon monoxide in the blood, which decreases its ability to carry oxygen to a developing fetus.

What we seem to gain from these studies is statistical evidence that suggests that prenatal cannabis use is on the rise, but that’s it. There are no studies – that I could find – comparing the use of edibles versus a water pipe or the long-term effects on the children who were exposed to cannabis in utero. The THC content in some cannabis is higher now making the findings of older studies irrelevant. New research needs to be done, under a multitude of controls and environments, to mirror the current reality of cannabis use in today’s society before we’ll have definitive answers either way.

When questions surrounding cannabis and pregnancy arise, the natural next step is breastfeeding. So, it may not be safe to consume cannabis while you’re pregnant, but what about while you’re breastfeeding? Cannabis is stored in fat cells and metabolizes slowly over time, meaning there can be cannabinoids present in your system weeks after your last use. The body uses fat to make breast milk and, like the placental barrier, THC may enter the breast milk and in turn, a breastfeeding child. But also like the placental barrier, there is little to no information on other cannabinoids or how they might affect a breastfeeding child developmentally or long-term. Breastfeeding and prenatal cannabis use are similar in that there is such a lack of scientific data, it’s difficult for doctors to say that any amount of cannabis is safe during pregnancy or breastfeeding. With that said, there are a few things to consider, but also keep in mind that many of the studies used for reference are old, incomplete or inconclusive.

Some studies have suggested that cannabis exposure “may affect” the development of movement, coordination and strength. Others have suggested that women who use cannabis may not breastfeed for as long, but it’s unclear as to whether this relates directly to cannabis. If smoking is your go to, limit the baby’s exposure to secondhand smoke. I know a mother who used edibles while breastfeeding to help her and baby sleep, but a sleepier baby can mean less eating which can lead to slower development and can be serious for underweight or premature babies. Last but not least, cannabis may affect your awareness, affecting the ability to care for a baby.

In my experience, pregnancy can cause a shift in lifestyle, from the subtle to the extreme, and I believe that cannabis use is a thing that will need to shift with you during that time. It can be frustrating. Most cannabis users are aware of how useful it can be for a myriad of problems but we have no solid evidence on how it may affect pregnant people or their offspring, short or long term. We just don’t know if it’s safe. For example, a pregnant person with a seizure disorder may need to continue CBD treatments to ensure both their health and their child’s, but CBDs can cause high brain activity that may not be healthy for a growing brain during fetal or early childhood development. So, the best advice is to do your own research and use the facts and science we have now, like smoking anything isn’t great for you. With more progressive cannabis laws comes the opportunity for more expansive and conclusive cannabis and pregnancy research, and this is one area where it’s currently severely lacking.


Laura Mastropietro

Laura Mastropietro, former cannabis co-op grower and patient advocate, consultant, Edible Chef for two edible lines, featured in ‘Cannabis Saved my Life’ by Elizabeth Limbach, currently curates a learning hub called, stays active in the cannabis community while running a restaurant and commercial bakery in beautiful Sedona Arizona. Wife, Mother, Grandmother, with a full beautiful life and toss in a life altering disease, cannabis is the magic that helps her keep it all going. Have a cannabis question? Send it to Dear Mama at

#Cannabis #kellymahoney #Pregnancy #Health #September2019 #mothers


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