Self-report and urine tests moderately agreed on cannabis use during pregnancy
Self-report and urine drug screening for cannabis during pregnancy showed only moderate agreement (kappa=0.49), with discordant results explained by low-level use undetected by urine tests and pre-awareness-of-pregnancy use detected by urine but not reported.
Quick Facts
What This Study Found
Concordance between self-report and urine drug screen was moderate (k=0.49). SR+/UDS+ (n=107), SR-/UDS- (n=142), SR+/UDS- (n=44, less frequent use), SR-/UDS+ (n=40, often used before knowing they were pregnant). Over 50% of discordant cases became concordant by trimester 2. Using SR+ and/or UDS+ as exposed changed classification minimally.
Key Numbers
333 participants (88.6% Black, 45.4% below poverty). Kappa=0.49. SR+/UDS+: 107. SR-/UDS-: 142. SR+/UDS-: 44. SR-/UDS+: 40. 35% of SR-/UDS+ reported secondhand exposure or blunt use. Over 50% of discordant cases resolved by trimester 2.
How They Did This
CUDDEL Study analyzing 333 pregnant individuals (88.6% Black, mean age 26.6) with both self-report and first-trimester urine drug screens. Concordance assessed with kappa statistic and groups characterized by demographics, use patterns, and exposure history.
Why This Research Matters
Accurately measuring prenatal cannabis exposure is essential for research on fetal outcomes. This study shows neither self-report nor urine screening alone captures the full picture, with important implications for how prenatal cannabis studies classify exposure.
The Bigger Picture
The finding that relying on self-report provides "adequate approximation" of cannabis use is reassuring for large epidemiological studies that cannot collect biological specimens. However, the 12% SR-/UDS+ rate means significant underestimation occurs in some populations.
What This Study Doesn't Tell Us
Predominantly Black, urban, lower-income sample may not generalize. CUDDEL Study recruited women with lifetime cannabis use history. UDS has limited detection window. Secondhand exposure may cause positive UDS without active use.
Questions This Raises
- ?Should prenatal cannabis research use both self-report and biological testing?
- ?How does secondhand cannabis exposure affect fetal outcomes?
Trust & Context
- Key Stat:
- Kappa=0.49 (moderate agreement)
- Evidence Grade:
- Well-designed concordance study with both measurement methods, but limited to one site with a specific demographic profile.
- Study Age:
- 2024 analysis from the CUDDEL Study of pregnant individuals
- Original Title:
- Characteristics of women concordant and discordant for urine drug screens for cannabis exposure and self-reported cannabis use during pregnancy.
- Published In:
- Neurotoxicology and teratology, 103, 107351 (2024)
- Authors:
- Bogdan, Ryan(14), Leverett, Shelby D(2), Constantino-Petit, Anna M, Lashley-Simms, Nicole, Liss, David B, Johnson, Emma C, Lenze, Shannon N, Lean, Rachel E, Smyser, Tara A, Carter, Ebony B, Smyser, Christopher D, Rogers, Cynthia E, Agrawal, Arpana
- Database ID:
- RTHC-05148
Evidence Hierarchy
Frequently Asked Questions
Can urine tests always detect cannabis use during pregnancy?
No. 44 women who reported using cannabis had negative urine tests, likely because they used infrequently enough that levels were below detection thresholds.
Why did some women test positive but deny use?
40 women denied use but tested positive. Many had used before knowing they were pregnant (62.5%), and 35% reported secondhand exposure or blunt use that may have contributed to positive tests.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-05148APA
Bogdan, Ryan; Leverett, Shelby D; Constantino-Petit, Anna M; Lashley-Simms, Nicole; Liss, David B; Johnson, Emma C; Lenze, Shannon N; Lean, Rachel E; Smyser, Tara A; Carter, Ebony B; Smyser, Christopher D; Rogers, Cynthia E; Agrawal, Arpana. (2024). Characteristics of women concordant and discordant for urine drug screens for cannabis exposure and self-reported cannabis use during pregnancy.. Neurotoxicology and teratology, 103, 107351. https://doi.org/10.1016/j.ntt.2024.107351
MLA
Bogdan, Ryan, et al. "Characteristics of women concordant and discordant for urine drug screens for cannabis exposure and self-reported cannabis use during pregnancy.." Neurotoxicology and teratology, 2024. https://doi.org/10.1016/j.ntt.2024.107351
RethinkTHC
RethinkTHC Research Database. "Characteristics of women concordant and discordant for urine..." RTHC-05148. Retrieved from https://rethinkthc.com/research/bogdan-2024-characteristics-of-women-concordant
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.