Table 1 Summary of basic characteristics of selected studies

1

Joy [17]

RCT

Intramural preterm (<37 weeks gestational age) VLBW infants (birth weight 1000–1500 g) who reached full enteral feeds of 180 mL/kg/day by 2 weeks postnatal age

colloidal ferric hydroxide

early

PO; 2 mg/kg/day start at 2 weeks postnatal age

52

32.4 ± 1.7

1.35 ± 0.15

27/23

12 weeks

late

PO; 2 mg/kg/day start at 6 weeks postnatal age

52

32.4 ± 1.6

1.33 ± 0.14

24/26

2

Sankar [18]

RCT

Preterm VLBW (<1500 g) infants who reached at least 100 mL/kg/day of oral feeds by day 14

colloidal iron

early

PO; 3–4 mg/kg/d at 2 weeks

22

32.4 ± 1.8

1.189 ± 0.228

12/10

60 days

late

PO; no iron until 60 days

24

31.5 ± 2.6

1.213 ± 0.196

12/12

3

Arnon [19]

RCT

All infants with a gestational age of 32 weeks who were fed human milk and reached enteral intake of 100 mL/kg/d

Iron trivalent (III)– hydroxide polymaltose complex

early

PO; 5 mg/kg/d enteral iron polymaltose complex at 2 weeks

32

18/12

8 weeks

late

PO; 5 mg/kg/d enteral iron polymaltose complex at 4 weeks

36

14/16

4

Franz [21]

RCT

All inborn infants with a birth weight of < 1301 g

ferrous sulfate

early

PO; 2–4 mg/kg/d oral iron once enteral feeding was tolerated

105

na

61 days

late

PO; started at 61 days of life at a dose of 2 mg/kg/day.

99

5

Jansson [20]

RCT

LBW infants with a birth weight ≦2000 g and/or a gestational age of ≦35 weeks

ferrous succinate

early

PO; 2–3 mg/kg/day from 3 weeks of age

15

1.855 ± 0.430

na

1-2 days; 8–10 weeks; 6 months

late

PO; 2–3 mg/kg/day from 2 months of age

13

1.779 ± 0.327