Despite positive effects from direct CBD exposure, mice exposed to CBD during pregnancy and nursing showed increased anxiety and thousands of altered DNA methylation sites in their brains as adults.
Reproductive health researchers, epigeneticists, and clinicians advising pregnant patients about CBD use.
Thousands of brain DNA methylation changes in offspring exposed to CBD during development
What the researchers found
F1 offspring exposed to CBD during development exhibited increased anxiety and improved memory in a sex-specific manner. Thousands of differentially methylated loci were identified in cerebral cortex and hippocampus, with functional enrichment for neurogenesis, substance use phenotypes, and other psychologically relevant terms.
Why it matters
This is the first study to examine developmental CBD exposure effects on offspring behavior and epigenetics, raising important questions about CBD use during pregnancy and breastfeeding.
The numbers in context
CBD dose: 20 mg/kg daily. Exposure window: 2 weeks pre-mating through lactation. Thousands of differentially methylated loci identified in both cerebral cortex and hippocampus of offspring.
How the study worked
Female mice received 20 mg/kg CBD or vehicle daily from two weeks before mating through gestation and lactation. Adult F1 offspring underwent behavioral testing (spatial memory, anxiety/compulsive behavior) and reduced-representation bisulfite sequencing of brain tissue.
What this study cannot tell us
Animal study in mice. CBD dose (20 mg/kg) may not reflect typical human exposure. Agouti mouse model has specific genetic characteristics. Behavioral effects were sex-specific, complicating interpretation.
How to read the evidence
Novel animal study with rigorous epigenetic methodology, but requires human validation.
When this study was published
Published in 2021.
The bigger picture
With CBD products increasingly used by pregnant and nursing women, understanding how developmental exposure affects offspring brain development and behavior becomes a pressing public health question.
Questions still open
- Do these epigenetic changes persist throughout the lifespan? Would lower CBD doses produce similar effects? Are there critical windows during development where CBD exposure matters most?
Common questions
Does CBD during pregnancy affect offspring brain development?
Were the effects the same in male and female offspring?
Read the original research
Developmental cannabidiol exposure increases anxiety and modifies genome-wide brain DNA methylation in adult female mice.
Clinical epigenetics, 13(1), 4
Citation
Wanner, Nicole M; Colwell, Mathia; Drown, Chelsea; Faulk, Christopher. (2021). Developmental cannabidiol exposure increases anxiety and modifies genome-wide brain DNA methylation in adult female mice.. Clinical epigenetics, 13(1), 4. https://doi.org/10.1186/s13148-020-00993-4
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