A cohort study of 250 children by American scientists, 80 of whom were exposed to cannabis prenatally (during the mother's pregnancy), showed that it was associated with a deterioration in attention, inhibitory control, and planning ability. In addition, as reported in JAMA Pediatrics, such children showed increased aggression at age five.
The maternal cohort also had high rates of tobacco, substance use, and alcohol use during pregnancy, according to researchers led by Sarah Keim of the Research Institute at Nationwide Children’s Hospital. Most families in the cohort lived in poverty. Age-adjusted standardized measures of attention and inhibitory control were about 0.4 standard deviations lower among those who used cannabis.
