Maternal THC use increased significantly in Arkansas, especially after state legalization
THC was the most common substance detected in newborn drug screening at an Arkansas hospital, found in 64% of positive results, and THC-positive rates increased significantly over the study period, particularly after state legalization.
Quick Facts
What This Study Found
Among 450 positive meconium drug screens, THC was most common (64.2%), followed by amphetamines (11.1%) and opioids (6.7%). The adjusted positive rate increased from 6.8% to 7.4% over 2018-2023. THC use increased more than other substances and the increase accelerated after state legalization. Infants with positive screens had lower birth weight, height, head circumference, and longer hospital stays.
Key Numbers
8,030 live births, 957 screened, 450 positive (47%). THC: 64.2% of positives. Adjusted positive rate: 6.8% to 7.4% over study period. 17.8% positive for multiple substances. Smoking mothers: OR 2.39 for positive MDS.
How They Did This
Retrospective analysis of 957 mother-infant dyads with meconium drug screen results from 8,030 live births at a reference hospital in Arkansas (2018-2023). An adjusted monthly positive rate accounted for variable screening rates.
Why This Research Matters
Prenatal THC exposure is increasing alongside legalization, and this study documents measurable adverse neonatal outcomes. The acceleration of THC use after legalization adds urgency to the need for prenatal screening and intervention.
The Bigger Picture
Cannabis is increasingly perceived as safe during pregnancy, partly because of normalization through legalization. This study shows that prenatal cannabis exposure continues to rise and is associated with measurable adverse birth outcomes, even in a state that only recently legalized.
What This Study Doesn't Tell Us
Non-universal screening means true prevalence is unknown. Screening was provider-initiated, introducing selection bias. Cannot control for confounders like poverty, nutrition, and other substance use that accompany THC-positive results. Single hospital in one state.
Questions This Raises
- ?Would universal prenatal substance screening change intervention opportunities?
- ?How much of the THC increase is due to legalization versus changing reporting or detection methods?
Trust & Context
- Key Stat:
- of positive newborn drug screens were THC-positive, making cannabis the most detected substance in prenatal exposure
- Evidence Grade:
- Reasonable sample with adjusted rate calculation to account for variable screening, but non-universal screening and single-site design limit generalizability.
- Study Age:
- 2025 publication with 2018-2023 data.
- Original Title:
- Evaluating maternal drug use disparities, risk factors and outcomes in Northeast Arkansas: a pre, during, and post-COVID-19 pandemic analysis.
- Published In:
- BMC public health, 25(1), 509 (2025)
- Database ID:
- RTHC-06559
Evidence Hierarchy
Looks back at existing records to find patterns.
What do these levels mean? →Frequently Asked Questions
Is cannabis use during pregnancy harmful?
This study found infants exposed to substances (predominantly THC) had lower birth weight, shorter length, smaller head circumference, higher preterm rates, and longer hospital stays. However, these outcomes may partly reflect confounding factors like poverty and polysubstance use.
Did legalization increase prenatal cannabis use?
THC-positive rates increased more steeply after Arkansas legalized cannabis, though the study cannot prove causation. Legalization may reduce perceived risk of prenatal cannabis use.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-06559APA
Gomez Pomar, Enrique; Berryhill, Johnna; Bhattacharyya, Sudeepa. (2025). Evaluating maternal drug use disparities, risk factors and outcomes in Northeast Arkansas: a pre, during, and post-COVID-19 pandemic analysis.. BMC public health, 25(1), 509. https://doi.org/10.1186/s12889-025-21636-4
MLA
Gomez Pomar, Enrique, et al. "Evaluating maternal drug use disparities, risk factors and outcomes in Northeast Arkansas: a pre, during, and post-COVID-19 pandemic analysis.." BMC public health, 2025. https://doi.org/10.1186/s12889-025-21636-4
RethinkTHC
RethinkTHC Research Database. "Evaluating maternal drug use disparities, risk factors and o..." RTHC-06559. Retrieved from https://rethinkthc.com/research/gomez-2025-evaluating-maternal-drug-use
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.