Developmental pathways from prenatal marijuana exposure to Cannabis Use Disorder in young adulthood

Background: Earlier studies reported an association between prenatal marijuana exposure (PME) and cognitive and behavioral problems in the offspring. A recent publication demonstrated the relation between PME and offspring marijuana use at age 22. There are no reports of the association between PME and Cannabis Use Disorder (CUD) at 22years, the age when use of marijuana and CUD peak.

Methods: Subjects are from the Maternal Health Practices and Child Development Study, a longitudinal study of PME and other exposures during pregnancy. The cohort of mothers and their offspring has been followed since the fourth prenatal month through 22years of age. A path analysis was conducted on 590 mother-child pairs, representing 77% of the birth cohort, to examine potential pathways from PME to CUD in offspring at 22years of age.

Results: There is no direct effect of PME on CUD. There are, however, two indirect pathways from PME to CUD. In the first, the pathway from PME to CUD goes through offspring early age of marijuana onset. In the second, offspring depression at age 10 and early age of marijuana onset predict CUD.

Conclusions: Although there is no direct effect of PME on CUD, there are significant indirect pathways from PME to CUD that affect the rate of CUD in the population. Thus, PME, offspring depression, and an early age of marijuana initiation, are significant points for intervention. As marijuana is legalized in more states, the rates of marijuana use will increase significantly, including during pregnancy, and the consequences of the association between PME and CUD will become even more significant from a public health perspective.