Birth Size Outcomes in Relation to Maternal Blood Levels of Some Essential and Toxic Elements.

Exposures to toxic trace elements and deficiencies of essential trace elements during pregnancy may impact fetal growth. This study was conducted to determine the association between maternal blood levels of essential elements including manganese (Mn), copper (Cu), and zinc (Zn) and toxic elements including arsenic (As), cadmium (Cd), and lead (Pb) at the first trimester with neonatal anthropometric parameters. This cross-sectional study was conducted in 2019-2020 in Isfahan, Iran. Overall, 263 mother-infant pairs were recruited in the first trimester of pregnancy. Maternal whole blood was collected, and essential and toxic elements were determined by mass spectrometry (ICP-MS)-based method. Birth size measurements were performed according to standardized protocols. Geometric means and standard deviations of maternal blood concentrations of Mn, Cu, Zn, As, Cd, and Pb were 3.94 ± 0.82, 5.22 ± 0.57, 7.67 ± 0.58, 2.21 ± 0.77, - 0.59 ± 0.98, and 3.23 ± 0.72 µg/l, respectively. Mean age of mothers was 29.94 ± 5.22 years. Thirty-one (12.1%) neonates were preterm. Maternal blood Pb levels were negatively correlated with birth weight (β = - 0.22 (CI 95%: - 0.38, - 0.05) p = 0.010) and marginally with birth head circumference (β = - 0.14(CI 95%: - 0.29, 0.02), P = 0.094) after adjustment for potential confounder variables. There was no significant association between Mn, Cu, Zn, As, Cd, and birth size measurements. Reverse association was found between maternal blood Pb levels and birth weight and birth head circumference. There is limited evidence related to the association between essential and toxic elements during pregnancy with birth size measurements and pregnancy disorders. More studies are suggested to assess of the effect of the trace elements and birth outcomes.