Preterm or Low Birth Weight

Low birth weight is defined as an infant weighing less than 5 lbs 8 oz or 2500 gms. Preterm birth is any infant born less than 37 weeks gestational age.

Preterm and low birth weight infants are frequently discharged from the hospital growth-retarded and show reduced growth throughout childhood. Considerable attention has been directed toward improving the nutrition of these infants while they are in the hospital, including the development of special nutrient-enriched formulas and multinutrient fortifiers, which can be added to human milk.

Extremely preterm infants frequently experience impaired neurodevelopment, and poor growth is associated with impaired neurodevelopment. Long-term outcome data now show the neonatal period to be a critical one in terms of the effects of nutrition on later health and developmental outcomes.

Low-birth-weight infants who were breastfed had significantly higher developmental scores at 9 months of age than did formula-fed infants.1

Preterm infants are commonly discharged weighing little more than half the appropriate weight for a term infant at the equivalent postmenstrual age. Of more concern, more than 30 percent of these infants remained below the tenth percentile for weight at age 18 months, and more than 20 percent were below the tenth percentile at 7 to 8 year follow-up.

The use of a nutrient-enriched formula in preterm infants has been associated with improved short-term growth. The American Academy of Pediatrics recognized the importance of nutrient enriched formula in the first 9 months in these infants. The use of preterm formulas to a postnatal age of 9 months results in greater linear growth and weight gain.

Preterm or low-birth-weight infants served by the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) should receive a prescription for Enfacare or Neosure (22 calorie formulas) noting the qualifying diagnosis (prematurity or low birth weight) and the duration of treatment (9 months post natal age).2

Infants born small for gestational age fare better developmentally if fed human breast milk. Every effort should be made to support breastfeeding in these infants.3


  1. Morley, R et al. Neurodevelopment in Children Born Small for Gestational Age: A Randomized Trial of Nutrient-Enriched Versus Standard Formula and Comparison with a Reference Breastfed Group. Pediatrics. 2004;Vol 113, No3:515-521.
  2. Lucas, A., et. Al. Randomized trial of nutrient-enriched formula versus standard formula for post-discharge preterm infants. Pediatrics. 2001: Vol. 108, 703-711.
  3. Morley, R. et al.

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