Since the 1940s women have been prohibited from eating and drinking during labor because of the danger of aspirating stomach contents should general anesthesia be necessary. This is a critical review of the research on which prohibiting oral intake during labor has been based and includes studies demonstrating delay of gastric emptying in pregnant and laboring women. Problems in defining the scope of maternal mortality from aspiration during anesthesia are discussed, as well as other effects of prohibiting women from eating and drinking during labor. These include physiologic effects from short-term deprivation of oral intake which has been largely overlooked in the literature and requires further investigation. Psychologic effects have been neglected altogether and should also be examined.