Donor breast milk versus infant formula for preterm infants: systematic review and meta-analysis

Objectives: To compare the effect of donor breast milk with infant formula in preterm infants. Separate comparisons with formula were made for donor breast milk that was: (1) given as a sole diet; (2) given as a supplement to mother's own breast milk; and (3) fortified with macronutrients and micronutrients. The main outcomes were death, necrotising enterocolitis (NEC), infection, growth and development. Data sources: Electronic databases- Cochrane, CENTRAL, MEDLINE, EMBASE, CINAHL, and HMIC: DH. Review methods: Systematic review and meta-analysis of trials and observational studies of preterm or low birthweight infants. Results: Seven studies (including five randomised controlled trials), all from the 1970s and 1980s, fulfilled the inclusion criteria. All studies compared the effect of sole donor breast milk with formula (combined n = A71). One of these also compared the effect of donor breast milk with formula given as a supplement to mother's own milk (n = 343). No studies examined fortified donor breast milk. A meta-analysis based on three studies found a lower risk of NEC in infants receiving donor breast milk compared with formula (combined RR 0.21, 95% CI 0.06 to 0.76). Donor breast milk was associated with slower growth in the early postnatal period, but its long-term effect is unclear. Conclusion: Donor breast milk is associated with a lower risk of NEC and slower growth in the early postnatal period, but the quality of the evidence is limited. Further research is needed to confirm these findings and measure the effect of fortified or supplemented donor breast milk.