The effect of donor human milk on the length of hospital stay in very low birthweight infants: a systematic review and meta-analysis

Background Donor human milk (DHM) is an alternative to preterm infant formula if the mother's own milk is not available. Since the lactation period and preservation treatment of DHM are different from those of mother's own milk, we aimed to determine the reduction in the length of hospital stay by DHM compared to preterm infant formula. Methods In this systematic review, we searched PubMed/MEDLINE, EMBASE, and the Cochrane Library to retrieve studies on the impact of DHM on the clinical outcomes of preterm infants published before 1 November 2019. The study included very low birthweight (VLBW) infants taking either DHM or infant formula with data on the length of hospital stay. Data were analysed using Review Manager 5.3 software. Results The literature search yielded 136 articles, and four randomised controlled trials (RCTs) and eight observational studies met the inclusion criteria. A meta-analysis of the RCTs (N = 725) showed no reduction in the length of hospital stay in both the DHM and infant formula groups (- 0.22 days; 95% CI -6.38, 5.95 days), whereas that of the eight observational studies (N = 2496) showed a significant reduction in the length of hospital stay in the DHM group (- 11.72 days; 95% CI -22.07, - 1.37 days). A subgroup analysis of the RCTs revealed that the incidence of necrotising enterocolitis (NEC) was significantly lower in the DHM group when the analysis included high-quality RCTs (RR = 0.32; 95% CI 0.15, 0.69). Conclusions This systematic review of RCTs showed that DHM neither prolonged nor shortened the length of hospital stay in VLBW infants compared to preterm infant formula; however, it reduced the incidence of NEC, further validating the protective role of DHM in the health and safety of VLBW infants.