Medical Cannabis During Pregnancy and Breastfeeding: Is the Concern Fully Evidence-Based?

Medical cannabis use is steadily increasing worldwide, including among pregnant and breastfeeding women. This Perspective provides an overview of current evidence regarding cannabis exposure during pregnancy and lactation and its implications for clinical decision-making. The available literature indicates relatively consistent evidence linking prenatal Δ⁹-tetrahydrocannabinol (THC) exposure with adverse perinatal outcomes, including reduced birth weight, increased risk of preterm delivery, and potential neurodevelopmental effects, although the findings remain heterogeneous and often confounded. In contrast, evidence regarding cannabis exposure during breastfeeding is sparse, and long-term infant outcomes associated with postnatal exposure through breast milk remain insufficiently characterized. Data on isolated cannabidiol (CBD) exposure during pregnancy and lactation are particularly limited, and most available evidence derives from preclinical studies or pharmacokinetic modeling rather than clinical outcome studies. Current recommendations from major health organizations uniformly advise avoiding cannabis and cannabinoid use during pregnancy and breastfeeding. This Perspective highlights the need to interpret the evidence according to cannabinoid type, exposure period, route and pattern of use, and the distinction between recreational exposure and regulated medical use. Such distinctions are particularly important because evidence is relatively stronger for prenatal THC exposure, whereas data on CBD and lactational exposure remain limited and are derived largely from indirect clinical, pharmacokinetic, and preclinical sources. Within this evidence landscape, individualized clinical interpretation may be needed when exposure has already occurred, cessation is not immediately feasible, or maternal treatment decisions remain complex, while remaining anchored in current avoidance recommendations.