Abstract
This population-based cross-sectional study analyzed electronic health record data of pregnant individuals in an integrated health care delivery system in California to examine changes in prenatal cannabis use through self-report and urine toxicology testing during standard prenatal care between 2012 (n=33,546) and 2022 (n=43,415), and to test whether trends differed by race and ethnicity or age. The prevalence of prenatal cannabis use increased from 5.5% (95% CI, 5.3–5.8%) in 2012 to 9.0% (95% CI, 8.7–9.2%) in 2022 (adjusted prevalence ratio [aPR] 1.82, 95% CI, 1.72–1.92), with similar increases by toxicology test (aPR 1.70, 95% CI, 1.60–1.81) and self-report (aPR 2.12, 95% CI, 1.95–2.30). The increase in prevalence varied significantly across racial and ethnic and age groups, with the highest prevalence among Black individuals and those aged 13–24 across years. Although rates increased more slowly among groups with the highest prevalence of use, disparities persisted over time