Study Of Cord Blood Zinc Levels in Low and Normal Birth Weight Neonates and Correlate with Their Mother’s Serum Zinc Levels

Abstract

Background: Zinc is a divalent cation first isolated in 1509 and since then its importance has been increasingly recognised in human health and nutrition. Women are at increased risk of zinc deficiency during pregnancy because of high fetal requirements for zinc. Severe maternal zinc deficiency has been associated with poor fetal growth, spontaneous abortion and congenital malformations, whereas milder forms of zinc deficiency have been associated with low birth weight (LBW), intrauterine growth retardation, and preterm delivery. Birth weight is the single most important marker of perinatal and neonatal outcome. We conducted this study to know and compare the cord blood zinc levels in normal and low birth weight neonates and correlate these with their mother’s serum zinc levels.
Aim: To study and compare the cord blood zinc levels in normal and low birth weight neonates and correlate these with their mother’s serum zinc levels.
Material and Methods: This study is a comparative study conducted in a tertiary care hospital.All inborn newborns with birth weight >2.5 kg to 4kg’s and their mothers were labelled as ‘Group 1’ and ‘Group 1 mothers’ respectively. All inborn newborns with a birth weight of <2.5kg and their mothers were labelled as ‘Group 2’ and ‘Group 2 mothers’ respectively. Serum zinc was measured by using zinc reagent in semi-auto biochemistry machine. After delivery, baby’s weight was measured within 1 hour after birth with no clothing on electronic weighing scale.
Statistical Analysis: The statistical analysis was done with SPSS software. Mean, Mode, Medians of various quantitative variables were calculated to study the central tendency of the parameters, while standard deviations of the parameters were calculated to study their extent of dispersion. Parametric test such as students t-test was used to study association between two quantitative parameters. Non-parametric test such as Chi-square test was applied to study the association between two qualitative parameters. A p value <0.05 was taken as significant.

Results: In normal birth weight group 1 mean cord blood zinc level was 97.07±8.13μgm/dl whereas in low birth weight group 2 the mean cord blood zinc level was 83.73±10.18μgm/dl. On comparing mean cord blood zinc level in normal birth weight to low birth weight, the difference was statistically significant. The mean maternal zinc level in normal birth weight group 1 was 97.32±9.65 μgm/dl, whereas in low birth weight group 2 it was 88.42±14.56 μg/dl. The results show a significant association between maternal zinc levels and birth weight.
Conclusion: Present study showed the maternal serum zinc level in normal birth weight group neonates was significantly higher compared to maternal serum zinc levels of low birth weight group. The mean cord blood zinc levels in the normal birth weight group neonates were significantly higher compared to low birth weight group of neonates.