Please use this link to access this publication. ABSTRACT Cannabis is the most commonly used federally illicit substance during pregnancy in the United States, with an estimated prevalence of 3% to 30%. The American College of Obstetricians and Gynecologists and the American Academy of Pediatrics discourage cannabis use during pregnancy and breastfeeding due to safety concerns for the fetus and infant. Despite these recommendations, nearly half of active cannabis users continue use in pregnancy. In this review, we summarize cannabis pharmacology and metabolism with a focus on delta-9-tetrahydrocannabinol, the psychoactive component of the cannabis plant, highlighting its significance in quantifying exposure and the impact...