Abstract
Objectives: To evaluate the nutritional status of vitamin D in relation to calcium-regulating hormones and related minerals.
Methods: A cross-sectional study was conducted on 264 Saudi pregnant females and their babies (at term) living in the Jeddah area. Maternal and fetal concentrations of serum calcidiol and calcitriol were determined together with those of serum intact-PTH, calcitonin, HPL, prolactin, DBP, alkaline phosphatase, calcium, phosphate and magnesium.
Results: The means for maternal serum calcidiol and calcitriol were 47.49 nmol/L and 343.7 pmol/L, respectively. The means for fetal serum calcidiol and calcitriol were 34.02 nmol/L and 206.3 pmol/L, respectively. Subclinical vitamin D-deficiency (serum calcidiol <20 nmol/L, was detected in 24 females, giving an overall rate of 9.1%. The latter females showed significantly higher values for body weight and gravidity (p<0.05 in each case), as compared with females with adequate vitamin D status. The maternal serum levels of calcidiol correlated positively with serum calcitriol (r=0.609, p<0.001), serum calcium (r=0.216, p<0.001), serum magnesium (r=0.171, p<0.003), fetal serum calcidiol (r=0.759, p<0.001), fetal serum calcitriol (r=0.759, p<0.001), fetal serum phosphate (r=0.189, p<0.001) and fetal serum magnesium (r=0.103, p<0.049), respectively. Maternal serum calcidiol correlated negatively with intact-PTH (r-0.719, p<0.001) and fetal intact-PTH (r= -0.132, p<0.016), respectively. Stepwise multiple regression analysis demonstrated that intact-PTH, calcitriol, calcium and magnesium significantly contributed to the variation in maternal calcidiol. No significant neonatal morbidity was associated with subclinical vitamin D-deficiency in the studied population.
Conclusions: These observations provide detailed information on the nutritional status of vitamin D in the local pregnant females and their babies in relation to calcium-regulating hormones and minerals and demonstrate that 9.1% of the studied females exhibited subclinical vitamin D-deficiency and therefore the problem of vitamin D-deficiency in the local pregnant females needs to be targeted.