Mother’s Own Milk Compared With Formula Milk for Feeding Preterm or Low Birth Weight Infants: Systematic Review and Meta-analysis

We assessed the effect of feeding preterm or low birth weight infants with infant formula compared with mother's own milk on mortality, morbidity, growth, neurodevelopment, and disability.We searched Medline (Ovid), Embase (Ovid), and Cochrane Central Register of Controlled Studies to October 1, 2021.Forty-two studies enrolling 89 638 infants fulfilled the inclusion criteria. We did not find evidence of an effect on mortality (odds ratio [OR] 1.26, 95% confidence interval [CI] 0.91-1.76), infection (OR 1.52, 95% CI 0.98-2.37), cognitive neurodevelopment (standardized mean difference -1.30, 95% CI -3.53 to 0.93), or on growth parameters. Formula milk feeding increased the risk of necrotizing enterocolitis (OR 2.99, 95% CI 1.75-5.11). The Grading of Recommendations Assessment, Development, and Evaluation certainty of evidence was low for mortality and necrotizing enterocolitis, and very low for neurodevelopment and growth outcomes.In preterm and low birth weight infants, low to very low-certainty evidence indicates that feeding with infant formula compared with mother's own milk has little effect on all-cause mortality, infection, growth, or neurodevelopment, and a higher risk of developing necrotizing enterocolitis.