Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effect of early fortification of human milk versus late fortification on growth and incidence of NEC in preterm infants; and to assess whether the effect varies based upon gestational age, birth weight, or type of fortifier (bovine‐milk‐based HMF or human‐milk‐based HMF or formula powder fortification).