The management of a newborn born to a mother with chorioamnionitis is controversial. By using data collected on neonates born in the era of routine maternal screening for Group B Streptococcus, we calculate that the risk of early-onset sepsis in a hypothetical infant born at term to a mother with chorioamnionitis, who has a normal physical examination at birth, is likely substantially <1% if the mother's screen for Group B Streptococcus was negative. This low rate of sepsis calls into question current guidelines recommending treatment of all such newborns with intravenous antibiotics for 48 hours pending the results of a blood culture. Current guidelines for the management of infants born to mothers with chorioamnionitis also raise an important ethical issue; the recommendation to treat these infants with intravenous antibiotics is, in essence, a de facto determination of what constitutes unacceptable risk to the newborn. We argue that this determination is ultimately value-based and therefore requires broader deliberation than that which frequently occurs among medical experts who develop medical guidelines.