Clinical Takeaway
Cannabis use during pregnancy is linked to measurable suppression of key immune signaling proteins (cytokines) in the mother’s bloodstream. Because these cytokines play a critical role in supporting a healthy pregnancy, this suppression raises legitimate clinical concern about immune function in pregnant patients who use cannabis. Pregnant patients should be counseled that cannabis is not risk-free during pregnancy, and clinicians should screen for use as part of routine prenatal care.
#26 Cannabis Use During Pregnancy Is Associated with the Suppression of Circulating Maternal Cytokines.
Citation: Alshaarawy Omayma et al.. Cannabis Use During Pregnancy Is Associated with the Suppression of Circulating Maternal Cytokines.. Cannabis and cannabinoid research. 2026. PMID: 41104491.
Design: 0 Journal: 1 N: 2 Recency: 3 Pop: 3 Human: 1 Risk: 0
Prenatal cannabis use is increasingly common yet poorly characterized in terms of immunological effects, making this study clinically significant given that maternal immune dysregulation during pregnancy can compromise placental function and fetal development. The suppression of circulating maternal cytokines documented here provides mechanistic evidence that THC exposure may impair critical immune responses required to maintain healthy pregnancy and combat intrauterine infections. These findings establish a biological rationale for counseling pregnant patients about cannabis’s potential immunosuppressive effects and warrant larger studies to determine clinical consequences for maternal-fetal outcomes.
Abstract: INTRODUCTION: The prevalence of prenatal cannabis use has nearly doubled in the United States. Cannabinoid 2 receptors are predominately expressed in cells of the human immune system, and delta-9 tetrahydrocannabinol (THC), the primary active component of cannabis, has been shown to suppress immune responses. Despite these findings, there is very little evidence on the impact of cannabis use on maternal immune system. Here, we evaluate the association between urine-verified cannabis use and the levels of T helper cytokines in the maternal circulation. METHODS: This was an ancillary study of a prospective cohort of pregnant women who participated in the Michigan Archive for Research on Child Health study. Pregnant women (age ≥18 years) were recruited from 22 prenatal clinics in Michigan and matched on age, race, and tobacco smoking (n = 144). The urinary metabolite of delta-9 THC, 11-nor-9-carboxy-delta-9-THC (THC-COOH), was used to define cannabis use status. A bead-based assay was used for the simultaneous detection of maternal cytokines associated with cannabis use and pregnancy outcomes in previous studies. RESULTS: Repeated-measures linear mixed models indicated that urine-verified cannabis use was associated with the suppression of maternal pro-inflammatory cytokines including interferon gamma (β = -0.5; 95% confidence interval [CI] = -0.8, -0.1) and interleukin (IL)-12 (β = -0.3; 95% CI = -0.6, -0.05), as well as the anti-inflammatory IL-4 (β = -0.7; 95% CI = -1.3, -0.2) and IL-10 (β = -0.4; 95% CI = -0.7, -0.03). Similar results were observed when heavy cannabis use was defined using the top tertile of urinary THC-COOH at each trimester. CONCLUSIONS: Urine-verified cannabis use was associated with the suppression of pro- and anti-inflammatory T helper cytokines in a cohort of pregnant women, suggesting that cannabis use can lead to modest dysregulation of the maternal immune system. Additional studies are needed to investigate the role of maternal immune resp
🤰 This study adds to our understanding of cannabis’ immunomodulatory effects by demonstrating associations between prenatal cannabis use and suppressed maternal cytokine levels, which warrants clinical attention given the critical role of maternal immunity in fetal development and pregnancy outcomes. However, several important limitations constrain our interpretation: the observational design prevents causal inference, unmeasured confounders (such as socioeconomic factors, concurrent substance use, or underlying immune conditions) may explain the observed associations, and we lack long-term outcome data linking cytokine suppression to actual maternal or neonatal health consequences. The clinical significance of these cytokine changes during pregnancy remains unclear, as both excessive and insufficient immune activation can be problematic in the prenatal context. Until we have more robust evidence on functional outcomes, this research suggests that pregnant patients using cannabis should be counseled about these potential immune effects and encouraged to discuss their use with their obstetric providers, while recognizing that shared decision-making must account for their individual clinical circumstances and the reasons