Prenatal alcohol exposure is widely known to impair brain development in exposed offspring. Rodent studies have shown that developmental deficits in newborns related to altered levels of a brain chemical called serotonin, leading to subsequent alterations in patterns of neonatal acute pain responses and/or hypothalamic-pituitary-adrenal stress reactivity. New findings show a "blunted response" to an acutely painful event in alcohol-exposed human newborns, indicating that prenatal alcohol exposure may alter the brain's developing pain regulatory system.