Doctors have long warned women against drinking alcohol while pregnant. "There is no known safe level of alcohol consumption during pregnancy," according to one piece of advice. Abstaining until after giving birth gives a baby a "better chance of healthy brain growth and development," says another. In some countries, such counsel has been incorporated into health policies. But while the medical advice against prenatal drinking is solid, making related rules and advisories does not appear to reduce infant morbidity or injury, new research suggests. Using a US database of private insurance claim...