The study’s goal was to see if the time to first enteral feeding (EF) and the rate of progression are linked to necrotizing enterocolitis (NEC) or mortality. Secondary examination of prospectively collected data on very-low-birth-weight infants (VLBWI: 400–1500 g) born between 2000 and 2014 in 26 NEOCOSUR centres. 83.7 percent of 12,387 VLBWI survived without NEC, 6.6 percent had NEC and survived, and 9.6 percent had NEC and died or died without NEC (NEC/death). Time to initial EF (median = 2 days) was not linked with NEC after risk adjustment; however, postponing it was protective for NEC/death (odds ratio [OR] = 0.96; 95 percent confidence interval [CI] 0.93—0.99). A slower feeding advancement rate (FAR) was associated with a decreased risk of NEC (OR = 0.97; 95 percent CI = 0.94–0.98) and NEC/death (OR = 0.98; 95 percent CI = 0.96–0.99).

There was no link between an early initial EF and NEC in VLBWI, while postponing it was related with reduced NEC/death. A decreased risk of both outcomes was related with a slower FAR.