Ask Dr. Leigh: Can you use cannabis during pregnancy?

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Using cannabis can have a big impact on your physical and mental health—for better, and sometimes for worse. That’s why it’s important to consult a healthcare provider before experimenting.

Here at GreenState, cannabis clinician Dr. Leigh Vinocur is here to answer your questions on healthy living with cannabis.

Editor’s Note: The answer to this question is meant to supplement, not replace, advice, diagnoses, and treatment from a healthcare provider.  Always consult a medical professional when using cannabis for medicinal purposes, and do not disregard the advice of your healthcare provider because of anything you may read in this article. 

Q: Can you use cannabis during pregnancy?

A: As states have started to legalize cannabis for both recreational and medical use, we have seen an increase in its use during pregnancy while alcohol and tobacco use has declined. In states that have recreational cannabis, many have the attitude that it can be responsibly used just like alcohol in adults. As a physician, while I don’t disagree with that, we do have needed laws to prohibit and protect our children with respect to recreational use of alcohol, tobacco and cannabis. Additionally, we have extensive research that shows the harm caused to the unborn fetus when they are exposed to alcohol during pregnancy, causing fetal alcohol spectrum disorder.  However, the data is not as clear-cut for cannabis yet. We do have data on some of the dangers of regular use of cannabis in the normal adolescent brain. And we know the adolescent brain continues to develop until early adulthood, so imagine what potential effects could occur on a newly forming brain and central nervous system (CNS) of the unborn fetus.

Our endocannabinoid system is critical to our normal functioning and homeostasis, which is the maintenance of all of our physiological processes.  And we know external cannabis exposure can affect our internal endocannabinoid system with respect to its functioning and structural neural development in our central nervous system (CNS.) Likewise, we know the endocannabinoid system plays a critical role in early pregnancy during the first trimester when the fetus’ brain and CNS start to form.  Just as in adults, exposing a fetus to external phytocannabinoids in cannabis can lead to downregulating or decreasing our critical cannabinoid receptors, endogenous (internal) endocannabinoids and their required signaling for normal brain and CNS formation and development.

Additionally, there have been longitudinal studies following these children after prenatal exposure to cannabis. The data has been more conflicting with respect to growth or cognitive abnormalities when compared with other teratogenic drugs that cause developmental problems, such as alcohol.  However, there has been more consistent evidence of learning problems developing in these children as they age, leading to problems with attention, hyperactivity and executive functioning.

Another potential harm of prenatal cannabis use, unfortunately, comes from our public health system and child protective services, which disproportionality targets expectant mothers of color in poorer communities even in legalized states. It is very similar to the way prosecution for cannabis has unfairly and disproportionality targeted communities of color. While state laws vary, in general, public hospitals and clinics often do urine drug testing during prenatal visits, and then child protective service agencies use that information against mothers and families. And despite the risks not being anywhere near as dangerous as prenatal exposure to opioids or crystal meth, due to the federal schedule 1 status of cannabis, unfortunately, there is a potential risk of breaking up these families.

Lastly, recreational cannabis uses aside, I am cognizant of the risk some expectant mothers must take with necessary critical prescription medications during pregnancy, for conditions such as hypertension or seizure disorder. And this is a difficult issue for some women. However, there is often a greater severe risk to these mothers and their ability to carry to term if they don’t take those medications. And as a physician who also recommends cannabis for her patients, I still feel we are not at that level yet with medical cannabis science and its disease indications. We don’t have all the clinical research we need yet to deem cannabis a critical therapeutic agent that pregnant medical patients need to take. So, I ask my patients, with all the uncertainties that still prevail, why even take any risk at all if you don’t have to? And I have found overwhelmingly the majority of expectant mothers want the best chance for their babies and they agree.

Got cannabis questions? Ask Doctor Leigh. Send your questions to GreenState’s Assistant Editor Elissa Esher at and keep an eye out for new answers from Dr. Leigh Vinocur every month.

Dr. Leigh Vinocur is a board-certified emergency physician who also has a cannabis consulting practice for patients and industry. She is a member of the Society of Cannabis Clinicians and a graduate of the inaugural class, with the first Master of Science in the country in Medical Cannabis Science and Therapeutics from the University of Maryland School of Pharmacy.

The response to this question was not written or edited by Hearst. The authors are solely responsible for the content.

Leigh Vinocur, MD