Cannabis Use During Pregnancy Suppresses Key Immune Signals in Mothers
Urine-verified cannabis use during pregnancy was associated with suppression of both pro-inflammatory and anti-inflammatory cytokines, suggesting modest immune dysregulation that could affect birth outcomes.
Quick Facts
What This Study Found
Cannabis use suppressed pro-inflammatory cytokines IFN-γ (β=-0.5) and IL-12 (β=-0.3) and anti-inflammatory cytokines IL-4 (β=-0.7) and IL-10 (β=-0.4) in pregnant women, indicating broad immune modulation rather than simple immunosuppression.
Key Numbers
144 matched participants; IFN-γ β=-0.5 (95% CI -0.8 to -0.1); IL-12 β=-0.3 (-0.6 to -0.05); IL-4 β=-0.7 (-1.3 to -0.2); IL-10 β=-0.4 (-0.7 to -0.03).
How They Did This
Ancillary prospective cohort study of 144 pregnant women from the MARCH cohort matched on age, race, and tobacco smoking, using urine-verified THC-COOH to define cannabis use and bead-based multiplex cytokine assays with repeated-measures linear mixed models.
Why This Research Matters
Pregnancy requires precise immune balance to protect both mother and baby — cannabis disrupting both pro- and anti-inflammatory signals could explain some of the adverse birth outcomes linked to prenatal use.
The Bigger Picture
This provides a potential biological mechanism for why cannabis use during pregnancy is linked to adverse outcomes — immune dysregulation during a period when precise immune balance is critical for fetal development.
What This Study Doesn't Tell Us
Modest sample size (n=144); observational design cannot establish causation; cytokine levels are systemic and may not reflect placental immune environment.
Questions This Raises
- ?Do these immune changes persist after cannabis cessation during pregnancy?
- ?Is the cytokine suppression dose-dependent?
- ?Could immune dysregulation explain specific adverse birth outcomes?
Trust & Context
- Key Stat:
- Evidence Grade:
- Well-matched prospective cohort with urine verification and repeated measures, but limited sample size and observational design prevent causal conclusions.
- Study Age:
- Published in 2026 from the NIH ECHO-affiliated MARCH cohort, using objective biomarker verification.
- Original Title:
- Cannabis Use During Pregnancy Is Associated with the Suppression of Circulating Maternal Cytokines.
- Published In:
- Cannabis and cannabinoid research, 11(1), 78-88 (2026)
- Authors:
- Alshaarawy, Omayma(9), Sotzen, Morgan, Kurjan, Emily, Padmanabhan, Vasantha, Ruden, Douglas M, Olson, L Karl
- Database ID:
- RTHC-08075
Evidence Hierarchy
Frequently Asked Questions
Does cannabis use during pregnancy affect the immune system?
Yes — this study found that cannabis use suppressed multiple immune signals in pregnant women, including both pro-inflammatory (IFN-γ, IL-12) and anti-inflammatory (IL-4, IL-10) cytokines.
Why does maternal immune suppression matter during pregnancy?
Pregnancy requires a carefully balanced immune system to support fetal development and prevent complications. Disrupting this balance could contribute to adverse outcomes like preterm birth or growth restriction.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-08075APA
Alshaarawy, Omayma; Sotzen, Morgan; Kurjan, Emily; Padmanabhan, Vasantha; Ruden, Douglas M; Olson, L Karl. (2026). Cannabis Use During Pregnancy Is Associated with the Suppression of Circulating Maternal Cytokines.. Cannabis and cannabinoid research, 11(1), 78-88. https://doi.org/10.1177/25785125251388764
MLA
Alshaarawy, Omayma, et al. "Cannabis Use During Pregnancy Is Associated with the Suppression of Circulating Maternal Cytokines.." Cannabis and cannabinoid research, 2026. https://doi.org/10.1177/25785125251388764
RethinkTHC
RethinkTHC Research Database. "Cannabis Use During Pregnancy Is Associated with the Suppres..." RTHC-08075. Retrieved from https://rethinkthc.com/research/alshaarawy-2026-cannabis-use-during-pregnancy
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.