Pregnant women in a large North American sample reported nearly double the rate of cannabidiol (CBD) use compared with nonpregnant women, new data published in a research letter in Obstetrics & Gynecology indicates.
Healthcare providers should be aware of the high rate of CBD use in pregnancy, especially as legal use of cannabis is increasing faster than evidence on outcomes for exposed offspring, note the researchers, led by Devika Bhatia, MD, from the Department of Psychiatry, Colorado School of Medicine, University of Colorado Anschutz Medical Campus in Aurora.
In an accompanying editorial, Torri D. Metz, MD, MS, deputy editor for obstetrics for Obstetrics & Gynecology, writes that the study “is critically important.” She points out that pregnant individuals may perceive that CBD is a safe drug to use in pregnancy, despite there being essentially no data examining whether or not this is the case.
Large Dataset From United States and Canada
Researchers used data from the International Cannabis Policy Study (2019-2021), a repeated cross-sectional survey of people aged 16-65 years in the United States and Canada. There were 66,457 women in the sample, including 1096 pregnant women.
Particularly concerning, the authors write, is the prenatal use of CBD-only products. Those products are advertised to contain only CBD, rather than tetrahydrocannabinol (THC). They point out CBD-only products are often legal in North America and often marketed as supplements.
The prevalence of CBD-only use in pregnant women in the study was 20.4% compared with 11.3% among nonpregnant women, P < .001. The top reason for use by pregnant women was anxiety (58.4%). Other top reasons included depression (40.3%), posttraumatic stress disorder (32.1%), pain (52.3%), headache (35.6%), and nausea or vomiting (31.9%).
“Nonpregnant women were significantly more likely to report using CBD for pain, sleep, general well-being, and ‘other’ physical or mental health reasons, or to not use CBD for mental health,” the authors write, adding that the reasons for CBD use highlight drivers that may be important to address in treating pregnant patients.
Provider Endorsement in Some Cases
Dr. Metz, associate professor of obstetrics and gynecology with the University of Utah Health in Salt Lake City, says in some cases women may be getting endorsement of CBD use from their provider or at least implied support when CBD is prescribed. In the study, pregnant women had 2.33 times greater adjusted odds of having a CBD prescription than nonpregnant women (95% confidence interval, 1.27-2.88).
She points to another cross-sectional study of more than 10,000 participants using PRAMS (Pregnancy Risk Assessment Monitoring System) data that found that “from 2017 to 2019, 63% of pregnant women reported that they were not told to avoid cannabis use in pregnancy, and 8% noted that they were advised to use cannabis by their prenatal care practitioner.”
The American College of Obstetricians and Gynecologists recommends against prescribing cannabis products for pregnant or lactating women.
Studies that have explored THC and its metabolites have shown “a consistent association between cannabis use and decreased fetal growth,” Dr. Metz noted. “There also remain persistent concerns about the long-term neurodevelopmental effects of maternal cannabis use on the fetus and, subsequently, the newborn.”
Limitations of the study include the self-reported responses and participants’ ability to accurately distinguish between CBD-only and THC-containing products.
Because self-reports of CBD use in pregnancy may be drastically underestimated and nonreliable, Dr. Metz writes, development of blood and urine screens to help detect CBD product use “will be helpful in moving the field forward.”
Study senior author David Hammond, PhD, has been a paid expert witness on behalf of public health authorities in response to legal challenges from the cannabis, tobacco, vaping, and food industries. Other authors did not report any potential conflicts. Dr. Metz reports personal fees from Pfizer, and grants from Pfizer for her role as a site principal investigator for SARS-CoV-2 vaccination and for her role as a site PI for RSV vaccination in pregnancy study.