Prenatal cannabis: A fetal neuroimaging study of neurodevelopment

PROJECT SUMMARY Current estimates suggest that in North America over 7% of women use cannabis during pregnancy and this use is increasing as legalization becomes more common. Despite the high prevalence of prenatal cannabis exposure, its effects on early brain and behavioral development remain poorly characterized, leaving some with the impression that this exposure is benign or potentially even beneficial (e.g., to treat nausea during pregnancy). Prior neurodevelopmental research on prenatal cannabis effects have had been important limitations including few if any brain/behavioral assessments during first two years of life (a period critical to neurodevelopment), poor characterization of the post-natal environment, and limited assessments of pre- and post-natal maternal mood and anxiety, thus confounding interpretation of prenatal cannabis effects. In our study, we will enroll pregnant women with (n=300) and without a history (n=150) of cannabis use during the first trimester gestation and follow their offspring for the first two years of life with a focus on the neurodevelopment of executive functions. First, we will characterize prenatal cannabis use through pregnancy with self-report measures and biospecimens. Second, we will obtain third trimester fetal MRI scans to character offspring brain structure and function free of post-natal confounds. Third, we will assess offspring cognitive and behavioral development over the first two years of life with parent-report and laboratory-based behavioral assessments. Our design considers critical confounds including parent-infant interactions, pre- and postnatal maternal mood and anxiety symptoms, shared genetic liability, and concomitant drug use during pregnancy. Given the lack of clarity on the safety of cannabis use during pregnancy, findings from this study will have important public health implications by informing prevention messaging and strategies particularly in this era of increasing cannabis use.