Abstract: A method for preventing or treating meconium aspiration syndrome (“MAS”) by administering a meconium aspiration syndrome preventing or treating amount of one or more complement inhibitors to a patient likely to develop or suffering from MAS. The complement inhibitors are preferably antibodies that bind to and inhibit complement proteins involved in the formation of the membrane attach complex, preferably anti-Factor D or anti-C5 antibodies. The complement inhibitors can be used alone or in combination with other MAS therapies to decrease the morbidity and mortality caused by MAS.