Children Exposed to Cannabis Before Birth Had Fewer Doctor Visits But More ER and Psychiatrist Visits

In a retrospective cohort of 508,025 Ontario infants (3,248 cannabis-exposed), prenatal cannabis exposure was associated with 14% fewer primary care visits (aRR 0.86, 95% CI 0.84-0.87), 29% more outpatient psychiatrist visits (aRR 1.29, 95% CI 1.00-1.66), 5% more ER visits (aRR 1.05, 95% CI 1.03-1.08), and 12% more hospitalizations (aRR 1.12, 95% CI 1.04-1.20). Among the highest income quintile, cannabis exposure was associated with a twofold increase in psychiatrist visits.

Retrospective cohort using linked perinatal and health administrative databases for all live singleton births in Ontario hospitals (April 2007-March 2012). Infants followed until March 2017 (up to age 10). Cannabis exposure identified from maternal self-report. Adjusted Poisson regression assessed differences in healthcare utilization rates.

This massive population-based study reveals a concerning pattern: children exposed to cannabis before birth visit primary care doctors less often but end up in emergency departments, hospitals, and psychiatrist offices more frequently. The reduced primary care suggests these families may face access barriers that lead to more acute healthcare needs.

The pattern of less preventive care and more acute care is a well-known marker of healthcare access disparities. While prenatal cannabis exposure may contribute to child health problems, the reduced primary care visits suggest socioeconomic and access factors play a significant role in the healthcare utilization differences observed.

Self-reported cannabis use (0.6% prevalence) likely underestimates true exposure. Cannot separate cannabis effects from confounding socioeconomic factors that drive both cannabis use and healthcare patterns. Administrative data lacks clinical detail. Cannot determine whether children's health problems were caused by cannabis exposure or related social determinants.