Understanding the Mechanism and Extent of Transplacental Transfer of (−)-∆9-Tetrahydrocannabinol (THC) in the Perfused Human Placenta to Predict In Vivo Fetal THC Exposure

Cannabis use during pregnancy may cause fetal toxicity driven by in utero exposure to (−)-∆⁹-tetrahydrocannabinol (THC) and its psychoactive metabolite, (±)-11-hydroxy-∆⁹-THC (11-OH-THC). THC concentrations in the human term fetal plasma appear to be lower than the corresponding maternal concentrations. Therefore, we investigated whether THC and its metabolites are effluxed by placental transporters using the dual cotyledon, dual perfusion, term human placenta.