Serum zinc and copper concentrations in Nigerian women with normal pregnancy

Abstract

The impact of normal pregnancy on serum zinc and copper concentrations and on copper/zinc ratio has been determined in a cross-sectional study of eighty-four healthy pregnant Nigerian women. Fifty-seven healthy non-pregnant women served as controls. Serum zinc and copper levels were determined by atomic absorption spectroscopy. Mean serum copper concentration is significantly higher (P < 0.001) in the pregnant group than in controls [19.74(4.65) and 11.87(2.61) micromol/L respectively], while mean zinc level is significantly lower (P< 0.001) than in controls [4.40(1.34) and 5.54(1.04) micromol/L respectively. Copper/Zinc ratio is also significantly higher than (P<0.001) in the test subject [4.87(1.77) and 2.23(0.75) micromol/L respectively]. One-way analysis of variance shows that the mean serum zinc and copper concentrations and copper/zinc ratio differ significantly (P < 0.01, P < 0.05, and P < 0.05 respectively) between any two of the trimester groups. Furthermore, there is a significant positive correlation between gestational age and copper/zinc ratio (r- 0.201; P < 0.05), and a significant negative correlation between gestational age and serum zinc concentration (r = -0.274; P < 0.01). In normal pregnancy, a negative and positive linear relationship exists between gestational age and serum zinc level and copper/zinc ratio respectively. Serum copper does not show any significant trend throughout gestation, though pregnant subjects have higher mean serum copper level than controls.