Vitamin Supplementation for Infants 2000-2500g
Direct Recommendation
Infants weighing 2000-2500g (marginally-low-birth-weight) should receive iron supplementation at 1-2 mg/kg/day starting between 2-6 weeks of age and continuing until at least 6 months, along with vitamin D 400 IU/day for breastfed infants. 1
Iron Supplementation Protocol
Both American and European guidelines specifically address this weight category:
- Start iron at 1-2 mg/kg/day between 2-6 weeks of age for infants weighing 2000-2500g 1
- Continue supplementation until at least 6 months of age 1
- This lower dose (compared to <2000g infants who need 2-3 mg/kg/day) reflects their intermediate risk status 1
Rationale: These marginally-low-birth-weight infants have lower iron endowment at birth compared to term infants, placing them at higher risk for iron deficiency anemia during rapid growth phases 1. They require supplementation beyond what breast milk or formula alone provides, but less than smaller preterm infants.
Vitamin D Supplementation
For breastfed infants in this weight category:
- Provide 400 IU/day starting in the first days of life 2
- This applies regardless of birth weight if the infant is exclusively or predominantly breastfed 2
- Breast milk does not provide adequate vitamin D 2
For formula-fed infants: Supplementation depends on the vitamin D content of the formula being used 3
Additional Vitamin Considerations
Vitamin K at birth:
- All newborns, including those 2000-2500g, must receive vitamin K at birth (0.5-1.0 mg) to prevent life-threatening vitamin K deficiency bleeding 2, 3
Multivitamin supplementation:
- Infants 2000-2500g who were born very preterm may benefit from continued multivitamin supplementation if they have not yet reached adequate caloric intake (300 kcal/day) 3
- However, once stable on full enteral feeds with adequate growth, routine multivitamin supplementation beyond vitamin D (for breastfed) and iron is not typically required 1
Critical Safety Points
Product selection matters:
- Never use adult multivitamin formulations in infants due to potential toxicity from propylene glycol and polysorbate additives 2, 4
- Use only pediatric-specific formulations 4
Special populations requiring enhanced supplementation:
- Small-for-gestational-age infants in this weight range need extra iron to achieve catch-up growth 1
- Infants with underlying conditions (cholestasis, cystic fibrosis, malabsorption) require individualized vitamin protocols 1
Monitoring Approach
Iron status:
- Clinical monitoring for signs of anemia is generally sufficient 1
- Routine laboratory monitoring is not required unless clinical concerns arise 1
Vitamin D: