Objectives: This study evaluated demographic patterns related to prenatal cannabinoid urine drug screening (UDS) over a 5-year period during which recreational marijuana was legalized and became accessible in Washington State.
Methods: Using electronic health record data, we performed a retrospective analysis for deliveries occurring over a 5-year period that encapsulated the transitions to marijuana legalization and legal access. For three cohorts of women delivering prior to legalization, between legalization and accessibility, and following accessibility, the UDS completion rate and screening demographic characteristics were assessed using Chi-squared tests and multivariate logistic regression.
Results: 25,514 deliveries occurred between March 2011 and March 2016. A significantly higher percentage of women underwent UDS post-accessibility (24.5%) compared to pre-legalization (20.0%, p < 0.001). A corresponding increase was not observed in the percentage of marijuana-positive UDS in tested patients (22.7% vs. 23.3%, p = 0.86). African American women had 2.8 times higher odds than Latinas of being tested, 2.1 times higher odds than Asian women, 1.7 times higher odds than White women, and 1.4 times higher odds than women of other races (all p < 0.001). Subsidized insurance status was also strongly associated with increased likelihood of testing (aOR = 3.5, p < 0.001).
Conclusions for practice: Prenatal UDS testing patterns changed as recreational marijuana possession and accessibility became legal. Demographic discrepancies in testing reveal biases related to race and insurance status, which may be a proxy for socioeconomic status. As such discrepancies are potential contributors to health outcome disparities, it is important for providers and health care systems to examine their practices and ensure they are being appropriately, equally, and justly applied.
Keywords: Health equity; Marijuana legalization; Maternal marijuana use; Prenatal care; Urine drug screening.