Aspiration is a potential problem in intubated infants who are fed enterally. In this prospective study, intubated preterm infants were fed orogastrically or oroduodenally. Aspiration was assessed by examining endotracheal aspirates for evidence of blue-colored dye. None of the babies had blue-colored endotracheal secretions when fed by either route. Heart and respiratory rates, blood pressure, and transcutaneous oxygen and carbon dioxide measurements were recorded at each interval of the study. There were no significant differences from baseline for these measurements. These findings indicate that there is no significant aspiration in intubated preterm infants who are fed by the orogastric or the oroduodenal route.