All of these facultative anaerobes persist at high levels in the fecal flora of preterm infants and there is significantly delayed colonization with anaerobes, especially Bifidobacteria, compared with that seen in healthy, full-term infants [31–33]. It has been suggested that the enteral administration of probiotics to preterm newborns could prevent infections, prevent NEC, and reduce the use of antibiotics [34]. Some other clinical trials of probiotic preparations to decrease the incidence of neonatal NEC are listed in Table 2.