Serum Level of Some Minerals during Three Trimesters of Pregnancy in Iranian Women and Their Newborns: A Longitudinal Study

Concentrations of various trace elements are altered during pregnancy with changes in the mother's physiology and the requirements of growing fetus. The aim of the present longitudinal study was to learn the changes of micronutrients Iron (Fe), Calcium (Ca), zinc (Zn) Magnesium (Mg) and copper (Cu) of pregnant woman and their relations with newborns levels. Serum levels of iron, calcium, zinc, magnesium and copper of 162 pregnant women and their newborns were determined by an inductively couple plasma mass spectrometer (ICP/MS). The results showed that majority (41 %) of pregnant women were in age group 26- 36 years 55 % had high school and diploma levels of education and the total income ranged between 3 and 5 Rials million per month There was significant difference in iron levels during first, second and third trimesters, 76.0 +/- 17.8, 63.5 +/- 15.2 and 70.1 +/- 14.4 mu g/dl respectively. Significant difference was shown in zinc levels 79.5 +/- 15, 74.5 +/- 16.1, and 65.3 +/- 14.9 mu g/dl during three trimesters. Copper levels during pregnancy were significantly different (130.9 +/- 43.5, 172.0 +/- 38.94, 193.2 +/- 28.5 mu g/dl. The serum levels of calcium and magnesium during pregnancy were constant (Ca: 8.96 +/- 0.48, 8.86 +/- 0.47, 8.91 +/- 0.42 mg/dl and Mg: 2.10 +/- 0.21, 2.08 +/- 0.28, 2.09 +/- 0.29 mg/dl). Results showed that 13 % of pregnant women had hypocalcaemia and hypomagnesaemia. Thirty eight percent and 42 % of pregnant women had iron and zinc deficiency respectively. In this study, unlike zinc, no pregnant women were found deficient in serum copper levels. Calcium, iron, zinc, copper and magnesium levels in the newborn's cord blood were 8.93 +/- 0.43, 106.0 +/- 26.1, 85.35 +/- 16.6, 57.04 +/- 13.8 and 1.99 +/- 0.27 mg/dl respectively. In the present study the levels of iron and zinc in cord blood were higher than the levels of iron and zinc in maternal serum. The mean level of copper in cord blood serum in the current study was lower than maternal values. The mean serum calcium and magnesium in the serum cord blood and in the serum of the pregnant women were similar.