Maternal serum vitamin D and parathormone concentrations during gestation and in umbilical cord blood - pilot study.

OBJECTIVE: We wanted to define levels of vitamin D (25(OH)D), parathormone (PTH), calcium (Ca), phosphorus (P) and the correlations between them during gestation as well as in umbilical cord blood.

METHODS: The study included 37 healthy singleton pregnant women in the course of gestation with no medical history concerning systemic diseases, nor with negative obstetrics and gynecological history. Biochemical parameters were determined using commercially available kits.

RESULTS: In the studied group, there were no significant differences in serum vitamin D, PTH, Ca and P concentrations in each trimester and during delivery. The negative significant association between serum 25(OH)D and PTH level was observed (r=-0.25; p< 0.05). Vitamin D levels during the summer season were significantly higher than observed in winter time in I (p< 0.01) and II trimester (p< 0.05), but not in III trimester. There was positive correlation between maternal serum and cord blood 25(OH)D (r= 0.74; p < 0.01). It was noted that 38-48% mothers had severe deficiency of vitamin D.

CONCLUSION: The study showed that regardless of the supplementation only 11-21% of studied pregnant women had optimal levels of vitamin D. The association between maternal and cord blood 25(OH)D suggested that inadequate vitamin D stores- during pregnancy may lead to a deficiency of this vitamin in newborns.