Prenatal tobacco and cannabis exposure linked to higher inflammation markers in young children | Research

The takeaway

Children exposed to tobacco or cannabis before birth showed elevated salivary C-reactive protein in early childhood, suggesting prenatal substance exposure may prime inflammatory pathways.

Researchers studying prenatal substance exposure, pediatric health professionals, and those interested in developmental origins of inflammation.

Biomarker-verified prenatal exposure showed stronger inflammatory associations than self-report

What the researchers found

Prenatal tobacco exposure was associated with higher salivary CRP in children at age 4-6, and prenatal cannabis exposure showed similar patterns, particularly when measured via biomarkers rather than self-report.

Why it matters

If prenatal substance exposure triggers lasting inflammatory changes, it could help explain downstream health and behavioral outcomes in exposed children. Inflammation is a pathway connecting early exposures to later disease.

The numbers in context

Prenatal tobacco and cannabis exposure were both associated with elevated salivary CRP in children at ages 4-6. Biomarker-verified exposure showed stronger associations than self-reported exposure alone.

How the study worked

Longitudinal study following mother-child pairs from pregnancy through early childhood. Prenatal exposure assessed via both self-report and biomarkers (cotinine, THC metabolites). Child inflammation measured by salivary C-reactive protein.

What this study cannot tell us

Salivary CRP is less well-validated than blood-based measures. Self-reported substance use likely underestimates true exposure. Observational design cannot confirm causation. Potential residual confounding from socioeconomic and environmental factors.

How to read the evidence

Longitudinal observational study with biomarker verification, but salivary CRP is a less established measure and residual confounding is possible.

When this study was published

Published 2022.

The bigger picture

Chronic low-grade inflammation in childhood has been linked to numerous health outcomes later in life. Understanding how prenatal exposures shape inflammatory biology could inform both prevention efforts and early intervention strategies.

Questions still open

Does the inflammatory signal persist into later childhood and adolescence? Are there critical windows during pregnancy when exposure has the largest impact on offspring inflammation?

Common questions

What is C-reactive protein?

CRP is a protein produced by the liver in response to inflammation. Higher levels indicate more systemic inflammation. It is commonly measured in blood but can also be detected in saliva, though salivary measurement is less standardized.

Does this prove cannabis causes inflammation in babies?

No. This is an observational study showing an association between prenatal cannabis exposure and higher CRP in young children. The design cannot prove causation, and other factors that differ between exposed and unexposed families could contribute to the pattern.

Read the original research

Associations between prenatal and postnatal substance exposure and salivary C-reactive protein in early childhood.

Neurotoxicology and teratology, 95, 107134

View on PubMed ↗Publisher’s paper ↗

Citation

Simon, Shauna G; Eiden, Rina D; Molnar, Danielle S; Huestis, Marilyn A; Riis, Jenna L. (2023). Associations between prenatal and postnatal substance exposure and salivary C-reactive protein in early childhood.. Neurotoxicology and teratology, 95, 107134. https://doi.org/10.1016/j.ntt.2022.107134