VITAMIN-D STATUS AND CALCIUM-REGULATING HORMONES IN SAUDI PREGNANT FEMALES AND THEIR BABIES - A CROSS-SECTIONAL STUDY

Objectives: To evaluate the nutritional status of vitamin D in relatio n to calcium-regulating hormones and related minerals. Methods: A cros s-sectional study was conducted on 264 Saudi pregnant females and thei r babies (at term) living in the Jeddah area. Maternal and fetal conce ntrations of serum calcidiol and calcitriol were determined together w ith those of serum intact-PTH, calcitonin, HPL, prolactin, DBP, alkali ne phosphatase, calcium, phosphate and magnesium. Results: The means f or maternal serum calcidiol and calcitriol were 47.49 nmol/L and 343.7 pmol/L, respectively. The means for fetal serum calcidiol and calcitr iol were 34.02 nmol/L and 206.3 pmol/L, respectively. Subclinical vita min D-deficiency (serum calcidiol <20 nmol/L, was detected in 24 femal es, giving an overall rate of 9.1%. The latter females showed signific antly higher values for body weight and gravidity (p<0.05 in each case ), as compared with females with adequate vitamin D status. The matern al serum levels of calcidiol correlated positively with serum calcitri ol (r=0.609, p<0.001), serum calcium (r=0.216, p<0.001), serum magnesi um (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. M aternal serum calcidiol correlated negatively with intact-PTH (r-0.719 , p<0.001) and fetal intact-PTH (r= -0.132, p<0.016), respectively. St epwise multiple regression analysis demonstrated that intact-PTH, calc itriol, calcium and magnesium significantly contributed to the variati on in maternal calcidiol. No significant neonatal morbidity was associ ated with subclinical vitamin D-deficiency in the studied population. Conclusions: These observations provide detailed information on the nu tritional status of vitamin D in the local pregnant females and their babies in relation to calcium-regulating hormones and minerals and dem onstrate that 9.1% of the studied females exhibited subclinical vitami n D-deficiency and therefore the problem of vitamin D-deficiency in th e local pregnant females needs to be targeted.