Cannabis use during pregnancy alters placental blood vessel markers and increases risk of pregnancy complications
In a study of 8,008 pregnant women, cannabis use before and during pregnancy was associated with altered placental angiogenic markers, higher placental-to-birth-weight ratio, and increased risk of pregnancy complications.
Quick Facts
What This Study Found
Cannabis use before and during pregnancy was associated with higher PlGF and lower sFlt-1/PlGF ratio in first and second trimesters. First-trimester-only cannabis use was associated with higher sFlt-1 and higher sFlt-1/PlGF ratio at delivery. Continued cannabis or tobacco use was linked to higher placental weight-to-birth-weight ratio and increased pregnancy complications.
Key Numbers
8,008 pregnant women. Cannabis use associated with higher PlGF and lower sFlt-1/PlGF ratio (both p<0.05). Continued use linked to higher placental weight-to-birth-weight ratio and more pregnancy complications (both p<0.05).
How They Did This
Population-based prospective cohort of 8,008 pregnant women. Tobacco and cannabis use assessed by questionnaires. Placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) measured in first trimester, second trimester, and at delivery from blood samples. Placental weight and complications from medical records.
Why This Research Matters
This is one of the largest studies to measure specific placental biomarkers in relation to cannabis use, providing mechanistic evidence for how cannabis may lead to adverse pregnancy outcomes.
The Bigger Picture
The finding that cannabis and tobacco both alter placental angiogenic factors, but in somewhat different patterns, suggests these substances affect placental development through overlapping but distinct mechanisms.
What This Study Doesn't Tell Us
Self-reported substance use likely underestimates true exposure. Cannot fully separate cannabis effects from tobacco (many co-use). Questionnaire-based assessment cannot capture dose or potency. Residual confounding possible.
Questions This Raises
- ?Do the altered angiogenic markers explain the increased complication risk, or are they simply correlates?
- ?Is there a safe timing or amount of cannabis use during pregnancy?
- ?Would the effects differ with CBD-only products?
Trust & Context
- Key Stat:
- Cannabis use altered placental markers across all three trimesters
- Evidence Grade:
- Large population-based prospective cohort with biomarker measurements, though self-reported exposure and potential confounding are limitations.
- Study Age:
- Published in 2022.
- Original Title:
- Maternal preconception and pregnancy tobacco and cannabis use in relation to placental developmental markers: A population-based study.
- Published In:
- Reproductive toxicology (Elmsford, N.Y.), 110, 70-77 (2022)
- Authors:
- Cajachagua-Torres, Kim N(4), El Marroun, Hanan(6), Reiss, Irwin K M(6), Jaddoe, Vincent W V
- Database ID:
- RTHC-03737
Evidence Hierarchy
Enrolls participants and follows them forward in time.
What do these levels mean? →Frequently Asked Questions
How does cannabis affect the placenta?
This study found cannabis use altered levels of PlGF and sFlt-1, proteins involved in placental blood vessel development. These changes were associated with a higher placental-to-birth-weight ratio and increased pregnancy complications.
Does the timing of cannabis use matter during pregnancy?
Yes. Continued use throughout pregnancy showed different marker patterns than first-trimester-only use, and continued use was associated with more complications. However, even first-trimester-only use showed altered markers at delivery.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-03737APA
Cajachagua-Torres, Kim N; El Marroun, Hanan; Reiss, Irwin K M; Jaddoe, Vincent W V. (2022). Maternal preconception and pregnancy tobacco and cannabis use in relation to placental developmental markers: A population-based study.. Reproductive toxicology (Elmsford, N.Y.), 110, 70-77. https://doi.org/10.1016/j.reprotox.2022.03.015
MLA
Cajachagua-Torres, Kim N, et al. "Maternal preconception and pregnancy tobacco and cannabis use in relation to placental developmental markers: A population-based study.." Reproductive toxicology (Elmsford, 2022. https://doi.org/10.1016/j.reprotox.2022.03.015
RethinkTHC
RethinkTHC Research Database. "Maternal preconception and pregnancy tobacco and cannabis us..." RTHC-03737. Retrieved from https://rethinkthc.com/research/cajachagua-torres-2022-maternal-preconception-and-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.