Table 1.

Characteristics of included randomized controlled trials

Authors	Year	n of Infants	Design	Inclusion criteria	Gestational age, week	Primary outcome(s)	Intervention	Duration of intervention/observation	Length of hospital stay, days (mean ± SD)	Fortification	Comments
Schanler et al. [37]	2005	243	Single blinded	GA ≤ 29 weeks	27 ± 2/ 27 ± 2	Incidence of late-onset; sepsis and NEC	Exclusively MOM MOM + DHM MOM + PF	90 days or discharge.	85.0 ± 53.0/ 90.0 ± 56.0	Bovine fortifier added to DHM group.	According to established criteria, DHM and PF groups were included.
O’Connor et al. [35]	2016	363	Double blinded	BW < 1500 g, enteral feeding within 7 day	27.5 ± 2.4/ 27.8 ± 2.7	Bayley-III score at 18 month; the incidence of NEC	MOM + DHM MOM + PF	90 days or discharge.	77.2 ± 53.0/ 73.2 ± 39.2	Bovine fortifier added to DHM group.	MOM + DHM group: MOM = 58% MOM + PF group: MOM = 63%
Cristofalo et al. [36]	2013	53	Double blinded	BW < 1250 g	27.7 ± 1.5/ 27.5 ± 2.4	Duration of parenteral nutrition; the incidence of NEC	Exclusive DHM Exclusive PF	91 days of age or discharge, or ≥ 50% oral feedings.	80.0 ± 32.1/ 90.0 ± 50.2	DHM fortifier added to DHM group.
Sullivan et al. [32]	2010	207	Single blinded	BW 500–1250 g, intention to provide MOM.	27.2 ± 2.2/ 27.3 ± 2.0	The incidence of NEC; parenteral nutrition, days; length of stay, days; bronchopulmonary dysplasia; weight gain	MOM+DHM MOM + PF	91 days or oral feedings or discharge.	80.1 ± 34.8/ 81.3 ± 24.2	Donor added to DHM group; bovine fortifier added to PF group.	Group HM100 and group PF received fortifier when enteral intake was 100 mL/kg/d. The gestational week refers to the two groups rincluded.

MOM mother’s own milk, PF preterm formula, DHM donor human milk, HM human milk, GA gestational age, BW birth weight, NEC necrotizing enterocolitis