Reference values of parathyroid hormone in very low birth weight infants.

Purpose: The primary goal was to estimate reference values of parathyroid hormone (PTH) in very low birth weight infants without severe neonatal morbidity. A secondary objective was to assess the relationship between PTH serum levels and selected laboratory markers of bone metabolism.

Methods: Ninety two infants with birth weight less than 1500 g met the inclusion criteria of the study.

Dynamics of the vitamin D C3-epimer levels in preterm infants.

Objectives: The primary objective was to determine levels of C3-epi-25(OH)D in very low birth weight infants. The secondary objective was to evaluate the possible influence of preterm birth, intrauterine growth restriction (IUGR), and season of birth on the production of C3-epimers.

Methods: A total of 127 infants with birth weight less than 1,500 g met the inclusion criteria of the study.