ABSTRACT
Intestinal dysbiosis is common in very premature infants and increases the risk of sepsis and necrotizing enterocolitis. Probiotics are dietary supplements that contain live microbes. Randomized placebo-controlled trials including more than 10,000 premature infants and observational cohort studies including more than 38,000 premature infants have demonstrated that prophylactic administration of probiotic microbes decreases the risk of necrotizing enterocolitis, sepsis, and death. Mechanisms include suppression of excessive inflammation, increased barrier stability resulting in decreased bacterial translocation, and alteration of the composition of the intestine. Probiotic administration for the prevention of NEC appears to be most effective when the premature infant is receiving human milk, likely due to synergism of these ingested microbes with components of human milk such as human milk oligosaccharides and lactoferrin. Future clinical trials and observational studies are needed to determine the optimum dose and strain(s) of probiotic microbes. Such studies will require large sample sizes.
