SummaryPreterm infants can not achieve intrauterine calcium and phosphorus accretion rate when fed with unsupplemented human milk or formulas with insufficient calcium and phosphorus content Since symptomatic or asymptomatic rickets may develop at 4 12 weeks of age in preterm infants who are not given sufficient calcium phosphorus and vitamin D human milk must be enriched with calcium and phosphorus until at least term age Preterm infants need for vitamin D being associated with the mother s vitamin D status may vary from 400 to 1200 U day Key words: Prematurity Rickets Calcium Phosphorus Vitamin D

Preterm infants can not achieve intrauterine calcium and phosphorus accretion rate when fed with unsupplemented human milk or formulas with insufficient calcium and phosphorus content Since symptomatic or asymptomatic rickets may develop at 4 12 weeks of age in preterm infants who are not given sufficient calcium phosphorus and vitamin D human milk must be enriched with calcium and phosphorus until at least term age Preterm infants need for vitamin D being associated with the mother s vitamin D status may vary from 400 to 1200 U day Key words: Prematurity Rickets Calcium Phosphorus Vitamin D