Please use this link to access this publication. Abstract Introduction: Human breast milk macronutrients play a vital role in the development of breastfed infants and are known to be influenced by several factors. There is limited information on the influence of cannabis use during lactation on these macronutrients. Given the rising use of cannabis among lactating women with its widespread legalization, this study aimed to examine the association of cannabis use during lactation on breast milk macronutrients. Materials and Methods: A cross-sectional study design was used and 637 breast milk samples with measured macronutrients were utilized. Of these, 165 samples that had detectable cannabis metabolites were...