Perinatal events and necrotizing enterocolitis in premature infants.

Among 2123 premature infants monitored during a large multicenter study of patent ductus arteriosus, necrotizing enterocolitis (NEC) was diagnosed in 121 (5.7%) of these infants. Rates ranged from 13.5% among infants with a birth-weight (BW) of 500 to 749 g to 2.9% among infants whose BW was between 1500 and 1750 g. The presence of a hemodynamically significant patent ductus arteriosus did not alter the incidence of NEC. Of a large number of perinatal events and conditions considered, only BW and maternal toxemia were found to be associated with the rate of NEC, both relating inversely. Thus, these data do not support a relationship between NEC and a variety of perinatal factors previously postulated as potential determinants of the disorder.