Prenatal Cannabis Use Linked to 3.7x Higher Risk of Sudden Infant Death in Genome-Wide Study
A genome-environment analysis of infant deaths found prenatal cannabis use was associated with a 3.7-fold higher risk of sudden unexpected infant death, rising to 6.0-fold after removing cases with strong genetic risk factors.
Quick Facts
What This Study Found
Among 212 SUID cases and 620,392 controls born in San Diego County (2005-2018), prenatal cannabis use was associated with an adjusted hazard ratio of 3.7 for SUID. When cases with strong genetic risk factors were removed, the cannabis association strengthened to aHR 6.0. WGS identified probable or possible genetic etiologies in 16% and 48% of SUID cases, with extreme genetic heterogeneity (144 loci, 173 risks).
Key Numbers
212 SUID cases; 620,392 controls; cannabis aHR 3.7 (overall), 6.0 (after removing genetic cases); 16% probable genetic etiology; 48% possible genetic etiology; 144 loci contributing 173 risks.
How They Did This
Genome-environment analysis linking births in San Diego County (2005-2018) to hospital discharge summaries and death files. 212 SUID cases vs. 620,392 controls. Whole genome sequencing of SUID cases combined with environmental risk factor analysis.
Why This Research Matters
This is the first large-scale study to combine genetic and environmental risk factors for SUID. The finding that cannabis risk strengthens after removing genetic cases suggests it operates through a different mechanism than the genetic causes, possibly representing a truly environmental risk.
The Bigger Picture
SUID (including SIDS) is the third leading cause of infant death with increasing incidence. The finding that prenatal cannabis is a strong risk factor, especially in non-genetic cases, adds to growing concerns about cannabis use during pregnancy and has implications for public health messaging.
What This Study Doesn't Tell Us
Preprint (not yet peer-reviewed). Prenatal cannabis identified from hospital records, likely underestimating true exposure. Cannot separate cannabis from polysubstance use entirely. San Diego County may not represent all populations. Genetic analysis of cases only, not controls.
Questions This Raises
- ?Through what biological mechanism might prenatal cannabis increase SUID risk?
- ?Would these findings replicate in cohorts with more detailed cannabis exposure data?
Trust & Context
- Key Stat:
- 3.7x higher SUID risk with prenatal cannabis (6.0x in non-genetic cases)
- Evidence Grade:
- Large cohort with novel genome-environment design, but preprint status, hospital-record cannabis ascertainment, and single-county sample limit strength.
- Study Age:
- 2025 preprint with 2005-2018 data
- Original Title:
- Genome x Environment analysis of Sudden Unexpected Infant Death unveils etiologic heterogeneity and strong cannabis and genetic disease risks.
- Published In:
- medRxiv : the preprint server for health sciences (2025)
- Authors:
- Kingsmore, Stephen F, Bandoli, Gretchen(8), Helbling, Daniel C, Baer, Rebecca, Blincow, Eric, Cao, Bryant, Frise, Erwin, Heinen, Alaina, Jelliffe-Pawlowski, Laura, Kobayashi, Erica Sanford, Kraan, Lucita Van Der, Kwon, Hugh, Lavy, Rishona, Moore, Barry, Oh, Danny, Oltman, Scott, Eric Ontiveros, Protopsaltis, Liana, Yandell, Mark, Chambers, Christina D
- Database ID:
- RTHC-06833
Evidence Hierarchy
Frequently Asked Questions
Does cannabis use during pregnancy increase SIDS risk?
This study found prenatal cannabis use was associated with a 3.7-fold higher risk of sudden unexpected infant death. The risk rose to 6.0-fold when cases with genetic explanations were excluded, suggesting cannabis may be an independent environmental risk factor.
What causes sudden infant death?
This study found SUID is highly heterogeneous: whole genome sequencing identified probable genetic causes in 16% of cases and possible genetic factors in 48%. Environmental risks including prenatal cannabis, other substance use, and Black race were also significant, especially in cases without strong genetic factors.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-06833APA
Kingsmore, Stephen F; Bandoli, Gretchen; Helbling, Daniel C; Baer, Rebecca; Blincow, Eric; Cao, Bryant; Frise, Erwin; Heinen, Alaina; Jelliffe-Pawlowski, Laura; Kobayashi, Erica Sanford; Kraan, Lucita Van Der; Kwon, Hugh; Lavy, Rishona; Moore, Barry; Oh, Danny; Oltman, Scott; Eric Ontiveros; Protopsaltis, Liana; Yandell, Mark; Chambers, Christina D. (2025). Genome x Environment analysis of Sudden Unexpected Infant Death unveils etiologic heterogeneity and strong cannabis and genetic disease risks.. medRxiv : the preprint server for health sciences. https://doi.org/10.1101/2025.11.26.25341098
MLA
Kingsmore, Stephen F, et al. "Genome x Environment analysis of Sudden Unexpected Infant Death unveils etiologic heterogeneity and strong cannabis and genetic disease risks.." medRxiv : the preprint server for health sciences, 2025. https://doi.org/10.1101/2025.11.26.25341098
RethinkTHC
RethinkTHC Research Database. "Genome x Environment analysis of Sudden Unexpected Infant De..." RTHC-06833. Retrieved from https://rethinkthc.com/research/kingsmore-2025-genome-x-environment-analysis
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.