Meta-analysis found prenatal cannabis may slightly raise ADHD risk but not autism in offspring
A meta-analysis of 534,445 participants found prenatal cannabis exposure slightly elevated ADHD risk (OR 1.13) and offspring cannabis use (OR 1.20), but was not associated with autism, psychosis, anxiety, or depression.
Quick Facts
What This Study Found
After adjusting for confounders, pooled ORs: ADHD 1.13 (95% CI 1.01-1.26); ASD 1.04 (0.74-1.46, not significant); psychotic symptoms 1.29 (0.97-1.72, not significant); anxiety 1.34 (0.79-2.29, not significant); depression 0.72 (0.11-4.57, not significant); offspring cannabis use 1.20 (1.01-1.42).
Key Numbers
18 studies, 534,445 participants. ADHD OR: 1.13 (1.01-1.26). ASD OR: 1.04 (0.74-1.46). Psychotic symptoms OR: 1.29 (0.97-1.72). Offspring cannabis use OR: 1.20 (1.01-1.42). Anxiety and depression: not significant.
How They Did This
PRISMA and MOOSE-compliant systematic review searching MEDLINE, EMBASE, and Cochrane through January 2024. 18 observational studies included (534,445 participants). Random-effects meta-analysis with confounder adjustment.
Why This Research Matters
This is the most comprehensive meta-analysis of prenatal cannabis and long-term neuropsychiatric outcomes. The small but significant ADHD association and the null findings for ASD, psychosis, anxiety, and depression help clarify a confusing literature.
The Bigger Picture
The finding that offspring of cannabis-exposed pregnancies were 20% more likely to use cannabis themselves raises questions about whether this reflects genetic heritability, in utero neurobiological priming, or shared environmental factors.
What This Study Doesn't Tell Us
All observational studies with potential residual confounding. Small effect sizes near the null. Limited studies for some outcomes (depression: few studies). Cannot account for increasing cannabis potency over time. Exposure measurement varies across studies.
Questions This Raises
- ?Is the ADHD association causal or driven by unmeasured confounders?
- ?Does increasing cannabis potency mean future pregnancies will show larger effects?
- ?Why does prenatal exposure predict offspring cannabis use?
Trust & Context
- Key Stat:
- ADHD OR 1.13; ASD not significant
- Evidence Grade:
- Large PRISMA-compliant meta-analysis with confounder adjustment provides strong evidence synthesis, though individual study quality varies.
- Study Age:
- 2024 meta-analysis searching databases through January 2024
- Original Title:
- Prenatal cannabis exposure and the risk for neuropsychiatric anomalies in the offspring: a systematic review and meta-analysis.
- Published In:
- American journal of obstetrics and gynecology, 231(6), 574-588.e8 (2024)
- Authors:
- Bassalov, Hely, Yakirevich-Amir, Noa(2), Reuveni, Inbal, Monk, Catherine, Florentin, Sharon, Bonne, Omer, Matok, Ilan
- Database ID:
- RTHC-05121
Evidence Hierarchy
Frequently Asked Questions
Does prenatal cannabis cause ADHD?
The meta-analysis found a small increased risk (13%), which was statistically significant. However, the effect size is small and could partly reflect unmeasured confounders. The authors note caution is warranted but call for more research.
Does prenatal cannabis cause autism?
This meta-analysis found no significant association between prenatal cannabis and ASD (OR 1.04), contradicting some individual studies that reported positive associations.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-05121APA
Bassalov, Hely; Yakirevich-Amir, Noa; Reuveni, Inbal; Monk, Catherine; Florentin, Sharon; Bonne, Omer; Matok, Ilan. (2024). Prenatal cannabis exposure and the risk for neuropsychiatric anomalies in the offspring: a systematic review and meta-analysis.. American journal of obstetrics and gynecology, 231(6), 574-588.e8. https://doi.org/10.1016/j.ajog.2024.06.014
MLA
Bassalov, Hely, et al. "Prenatal cannabis exposure and the risk for neuropsychiatric anomalies in the offspring: a systematic review and meta-analysis.." American journal of obstetrics and gynecology, 2024. https://doi.org/10.1016/j.ajog.2024.06.014
RethinkTHC
RethinkTHC Research Database. "Prenatal cannabis exposure and the risk for neuropsychiatric..." RTHC-05121. Retrieved from https://rethinkthc.com/research/bassalov-2024-prenatal-cannabis-exposure-and
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.