Keywords Placenta endocannabinoid system preterm birth gestational age metabolomics monoacylglycerols ▒ KEY MESSAGE Gestational age is the dominant driver of placental enndocannabinoid system (ECS) variation across gene and metabolite profiles. Spontaneous preterm placentas reflect earlier maturation, with elevated monoacylglycerols and higher PTGS2 expression under 32 weeks. These data refine ECS change interpretations preterm birth and suggest links to prostaglandin pathways in parturition.
