Guidelines: Preterm Infants Require Vitamin D Supplement

Larry Hand

April 29, 2013

Vitamin D supplementation is recommended for preterm infants both while they are still in the hospital and after discharge, according to dietary guidelines issued in a clinical report published online April 29 in Pediatrics. Calcium and phosphorous supplementation is also recommended early on.

Steven A. Abrams, MD, professor of pediatrics at Baylor College of Medicine in Houston, Texas, developed the guidelines along with the American Academy of Pediatrics Committee on Nutrition.

The guidelines contain the first dietary recommendations for vitamin D and calcium intakes specifically designed for preterm infants, who "have unique bone mineral requirements that may not be assumed to be similar to those of full-term newborn infants," the authors write. Institute of Medicine dietary guidelines issued in 2011 for calcium and vitamin D intake did not include recommendations for preterm infants.

Key elements to help prevent rickets in very low birth weight (VLBW) infants are absorbed calcium and phosphorous, the authors write, and unfortified human milk, parenteral nutrition, and infant formulas do not contain enough of these minerals to promote healthy bones in these infants. Vitamin D helps the infants absorb calcium.

To prevent rickets in preterm infants, the guidelines recommend that high amounts of mineral supplements be used with infants who weigh less than 1800 to 2000 g (almost 4 - 4.5 pounds). Supplementation should include human milk fortified with minerals or formulas designed specifically for preterm infants and should be based on infant weight rather than gestational age.

For vitamin D supplementation, the authors write: "On the basis of limited data, a vitamin D intake of 200 to 400 IU/day for VLBW infants is recommended. This intake should be increased to 400 IU/day when weight exceeds ~1500 g [about 3.5 pounds] and the infant is tolerating full enteral nutrition."

Decreasing mineral supplementation may begin after the infant weighs about 4.5 pounds, and infants with that weight "generally do well with exclusive breastfeeding or routine infant formula after discharge from the hospital," the authors write. Vitamin D supplementation after discharge could ensure that infants receive at least 400 IU/day.

The authors caution, however, that individual clinical conditions may call for some variation.

The guidelines also encourage the routine evaluation of bone mineral, using biochemical testing, for infants weighing less than 1500 g but not for those weighing more. In addition, the guidelines say that clinical evidence of fractures should prompt radiographic evaluation for rickets and management through maximizing calcium and phosphorous intake.

The authors conclude, "Small-for-gestational-age infants at or near term, such as is common in many global settings, may usually be provided minerals in the same way as larger infants of the same gestational age. Such infants should be monitored carefully for growth, and an adequate intake of vitamin D should be ensured."

The authors have disclosed no relevant financial relationships.

Pediatrics. Published online April 29, 2013.