OBJECTIVE: To identify neurobehavioral effects of prenatal marijuana exposure on neonates in rural Jamaica. DESIGN: Ethnographic field studies and standardized neuro-behavior assessments during the neonatal period. SETTING: Rural Jamaica in heavy-marijuana-using population. PARTICIPANTS: Twenty-four Jamaican neonates exposed to marijuana prenatally and 20 nonexposed neonates. MEASUREMENTS AND MAIN RESULTS: Exposed and nonexposed neonates were compared at 3 days and 1 month old, using the Brazelton Neonatal Assessment Scale, including supplementary items to capture possible subtle effects. There were no significant differences between exposed and nonexposed neonates on day 3. At 1 month, the exposed neonates showed better physiological stability and required less examiner facilitation to...