Evidence on the effect of in-utero cannabis exposure in neonates.
Level 5 - mechanism / opinion, no new human data
Narrative review summarizing existing literature without a systematic review protocol.
PubMed 40797024 · doi:10.1038/s41372-025-02383-1
What was done
This narrative review synthesized existing literature and meta-analyses to examine biological mechanisms, placental and breast milk transfer, and clinical outcomes associated with in-utero and lactational cannabis exposure in neonates.
What was found
The review notes that THC concentrations in cannabis products have risen from 5% to 30%, and breastfed infants receive approximately 2.5% of the maternal dose. Observational studies and meta-analyses show associations between prenatal cannabis exposure and low birth weight, preterm birth, neonatal intensive care unit admission, reduced Apgar scores, and long-term neurodevelopmental alterations affecting memory, attention, and executive function. No specific pooled effect sizes or statistical values are reported in the abstract.
Why it matters
With rising cannabis potency and use during pregnancy, clarifying transfer mechanisms and associated risks aids clinical counseling regarding maternal cannabis use during pregnancy and lactation.
Limits
The review relies on observational studies because randomized controlled trials are ethically impossible, leaving findings vulnerable to confounding. The abstract provides no specific quantitative risk estimates, search methodology, or study counts.
Cited by
- supports Tetrahydrocannabinol (THC) crosses the human placenta directly.