Necrotizing enterocolitis (NEC) is a medical condition primarily seen in premature infants, where portions of the bowel undergo necrosis (tissue death). It occurs postnatally (i.e. it is not seen in stillborn infants) and is the second most common cause of morbidity in premature infants, causing 342 deaths per year in the United States in 2012, down from 386 in 2011.