WHY IT MATTERS: Pregnant patients and those planning pregnancy should understand that current evidence links prenatal cannabis use to measurable changes in fetal development that may carry lasting neuropsychiatric consequences for their child. CLINICAL OVERVIEW: Emerging research is exploring whether placental biomarkers can serve as early indicators of schizophrenia risk, particularly in the context of prenatal cannabis exposure. THC crosses the placenta and can disrupt fetal neurodevelopment by interacting with the endocannabinoid system during critical windows of brain formation.