Cannabis Use in Pregnancy

Abstract

Concern for adverse effects of prenatal cannabis use (PCU) is warranted. The American Academy of Pediatrics recommends refraining from PCU, because Δ⁹-tetrahydrocannabinol (THC) crosses the placenta at approximately 10% of maternal levels, which can result in adverse offspring outcomes. Little is known about patterns and contexts of PCU; to advance this effort, 64 pregnant women who use cannabis were recruited from Amazon’s Mechanical Turk for a study of PCU thoughts and behaviors. Women were, on average, 22 years of age (range 22-49); mean income was ~$44,000 (range $0-$150,000). 53.3% of respondents were in the first trimester, 43.3% were in the second and 3.4% were in the third. Polysubstance use was common; 25% reported prenatal alcohol use and 64% reported prenatal tobacco use. Approximately 40% reported using about the same amount of cannabis as before pregnancy. Regarding availability and patterns, approximately 44% indicated that cannabis was “somewhat” or “very” easy to get. Women in the third trimester reported the most frequent PCU. Across all trimesters, the majority of women reported using cannabis with roughly equal parts THC and cannabidiol and PCU primarily consisted of consumption of leaf and concentrates. The most common modes of administration were joints in the first trimester and hand pipes in the second and third trimesters. On a typical PCU day, approximately 70% of participants reported consuming ¼ gram of flower or less, 73% reported taking 5 or fewer hits of concentrates, and 85% reported ingesting 10 milligrams of THC or less in edibles. PCU among social networks was prevalent; over 50% reported that their spouse/partner used cannabis during their pregnancy and approximately 80% reported that a few, several, or most of their family and friends use cannabis. Regarding contexts, during a typical week, women reported PCU in their homes (alone [30%], with others [54.7%]), at friends’ or family members’ homes (alone [28%], with others [39%]), in bars/nightclubs/restaurants/breweries (alone [30%], with others [34%]), as well as outdoors (alone [34%], with others [33%]), at work (alone [34%], with others [36%]), at school (alone [23%], with others [36%]), in the car (alone [31%], with others [36%]) or elsewhere (alone [23%], with others [39%]). PCU was perceived as ‘highly effective’ (as reported by 75-95%) at managing nausea, distress (anxiety, depression), and physical discomfort (e.g., backaches). Perceived harm of PCU was low, more than half of participants believed PCU would harm the fetus (~60%) or herself (~64%) “not at all” or “a little.” In conclusion, polysubstance use, particularly tobacco use, is common among women who use cannabis during pregnancy. Although quantity of PCU consumption was relatively low in our sample, any amount is concerning and may have negative impact on the developing fetus. The majority of women’s social networks used cannabis and, in all contexts (with the exception of outdoor use), PCU was typically in the company of others. Perceived efficacy of PCU for symptom modulation was high across a variety of conditions, and risk perceptions were low, both of which may result in riskier use trajectories.