Children of women who used cannabis while they knew they were pregnant may be at greater risk of symptoms of mental illness than children of women who did not use cannabis during pregnancy, according to a report in JAMA Psychiatry. For instance, youth who were exposed to cannabis in the womb were more likely to report more psychotic-like experiences, as well as problems with aggressive behavior, depression, and anxiety than those without such exposure.
“[P]regnant women, and even those contemplating pregnancy, should be discouraged from using any cannabis by health care professionals, dispensaries, and others,” wrote Ryan Bogdan, Ph.D., of Washington University in St. Louis and colleagues.
Bogdan and colleagues analyzed data from 11,489 children enrolled in the Adolescent Brain and Cognitive Development (ABCD) study—an ongoing study tracking the brain development of U.S. children through adolescence. Based on retrospective prenatal cannabis use reported by parents or caregivers of children in the study, the researchers divided the ABCD study participants into three groups: no exposure to cannabis (n=10,834), exposure to cannabis prior to maternal knowledge of pregnancy only (n=413), and exposure to cannabis after maternal knowledge of pregnancy (n=242). The average age of children in the study was 10.
The researchers used several validated questionnaires to measure outcomes in children including the Prodromal Questionnaire–Brief Child to assess child-reported psychotic-like experiences and the Child Behavior Checklist to assess internalizing problems (for instance, depression and anxiety) and externalizing problems (for instance, aggressive behavior) as well as attention, thought, sleep, and social problems.
The researchers found that children whose mothers had used cannabis before or after they learned they were pregnant were more likely to have psychotic-like experiences and increased internalizing and externalizing problems compared with children who had no prenatal exposure. Exposure later in pregnancy, after mothers had learned of their pregnancy, was related to greater psychiatric problems in children even after adjusting for possible variables such as family demographics.
“It is clear that more studies on the association between prenatal cannabis exposure and offspring developmental outcomes are needed to examine potential causal effects, moderating or protective factors, and biological mechanisms,” the researchers wrote. “Similar to the effective messaging surrounding the adverse consequences of alcohol and tobacco exposure during pregnancy, education regarding the potential harms associated with prenatal cannabis use is necessary.”
For related information, see the Psychiatric News article “Cannabis Use During Pregnancy on the Rise.”