Children exposed to cannabis prenatally showed decreased attention, inhibitory control, and planning abilities compared with unexposed children at age 5 years, according to a new study.

In the prospective cohort study, published in JAMA Pediatrics, investigators enrolled pregnant participants aged 16 through 50 years who were receiving prenatal care at Ohio State University Wexner Medical Center. The study population included 62% non-Hispanic Black children, 4% Hispanic children, 14% multiracial or other race non-Hispanic children, and 20% White non-Hispanic children. 

The study included 250 children between 2016 and 2020. The investigators identified 80 children (32%) with prenatal cannabis exposure through maternal urine toxicology, self-reporting, and obstetric record review.

Assessment methods included:

• NIH Toolbox Early Childhood Cognition Battery
• Tower of Hanoi task
• Disappointing gift task
• Child Behavior Checklist
• Bobo Doll task
• Behavior Rating Inventory of Executive Function.

Concurrent substance use occurred in 22% to 39% of participants reporting tobacco, alcohol, or other drug use during pregnancy. The investigators controlled for these potential confounders using propensity score weighting and multiple regression analyses.

The investigators found that exposed children scored approximately 0.4 standard deviations lower on attention and inhibitory control measures (β = –6.1 points, 95% confidence interval [CI] = –10.8 to –1.4) after adjusting for confounders. Additionally, exposed children demonstrated poorer planning ability on task-based assessments and exhibited more observed aggression during behavioral testing.

Key findings laboratory assessments revealed:

• Attention/inhibitory control scores were 6.1 points lower (95% CI = –10.8 to –1.4).
• Planning ability showed a 0.3 standard deviation decrease.
• Observed aggression increased by 17 percentage points in fisted hits to target.

Caregiver-reported measures showed no statistically significant differences between exposed and unexposed children. The investigators found no differences in cognitive flexibility, emotion regulation, or other executive function domains.

The study design included:

• Prospective exposure assessment using multiple detection methods
• Masked outcome assessment
• Diverse study population
• Comprehensive confounding control
• Multi-informant outcome measurement
• Modern computerized assessment tools.

Limitations included:

• Inability to determine specific timing and dose of exposure
• Potential exposure misclassification
• Possible residual confounding
• Some standardized measures originally developed with less diverse populations
• Missing outcome data for some participants.

The research occurred as cannabis use during pregnancy increased from 3.4% in 2002 to 7.2% in 2021, according to national survey data cited in the study.

Conflict of interest disclosures can be found in the study.