Biochemical changes in serum 25-hydroxy vitamin D3, 1,25-dihydroxy vitamin D3, parathyroid hormone, calcium and phosphorus during pregnancy and lactation

ABSTRACT

In this thesis, 25-hydroxy vitamin D[3] [25-[OH]D[3]], 1.25-dihydroxy vitamin D3 [1.25[OH[2]]2D[3]] and other relaIed serum constituents were determined in non-pregnant, non-lactating women, pregnant women at different periods of gestation and lactating mothers. The results showed a significant decrease in serum 25-OHD3 level in the early stage of pregnancy [8-16 week] as compared to the controls, while there was no difference between its values in both mid [20-28 week] and late [32-40 week] stages pregnant women, lactating mothers and the controls. The mean serum levels of [1.25[OH][2]D[3]] were progressively decreased till [20-28] weeks of gestation as compared to the controls, after that period, the level were non-significantly increased and nearly the same as that of the controls till the end of pregnancy and during lactation. During [8-16] and [32-40] week of gestation, the mean serum level of parathyroid hormone were significantly decreased than that of the non-pregnant controls, while there was no difference between its values in both mid stage pregnant women, lactating mothers and the control nonpregnant women. No statistical difference were found in the mean serum calcium level of the pregnant women during the different periods of pregnancy and the lactating women as compared to the control non-pregnant women. The mean serum phosphorus levels during the different periods of gestation were significantly higher than in the controls, while lactating mothers and the nonpregnant women had the same serum phosphorus levels