Cannabis Use During Lactation: Literature Review and Clinical Recommendations

Cannabis is the most commonly used psychoactive substance in Canada. The prevalence of cannabis use both during pregnancy and in the postpartum period has been estimated at 5% of the population. Women who use the drug during lactation place their infants at risk of exposure to cannabis and its metabolites in breast milk. This article provides a systematic review of infant outcomes associated with cannabis use by women during lactation followed by clinical recommendations. A review of the literature was conducted using Medline, Embase, and PsychInfo from their start to July 2018. Inclusion criteria consisted of articles addressing the impact of postpartum cannabis use by lactating women and providing developmental outcomes for infants. Two articles met these criteria and were included in our systematic review. Results indicate conflicting outcomes regarding the risk of exposure to cannabis in breast milk. Women should be advised to abstain from cannabis use during lactation or reduce consumption if abstinence is not possible. Furthermore, women should be advised to avoid breastfeeding within 1 hour of inhaled use to reduce exposure to highest concentration of cannabis in breast milk. Despite some evidence regarding health risks of post-natal exposure to cannabis, further research is needed to determine its impact on infant neurodevelopmental outcomes beyond the first year of life.