RESUMO
This study was done to measure vitamin C, ceruloplasmin and antioxidant activity of plasma at birth and their relation to gestational age. We also investigated whether the plasma antioxidant activity is influenced by the vitamin C to ceruloplamin ratio. We also investigated the relation between plasma antioxidant activity at birth and neonatal mortality. Blood samples were taken from 36 preterm newborns and 12 term newborns as a control group within two hours after birth. Plasma ascorbic acid, ceruloplasmin and antioxidant activity of plasma were measured. The premature infants were classified into 2 groups: Group I [survivors - 24] and group II [died, n = 12]. Compared to the full term newborns, the plasma antioxidant activity was significantly decreased [P<0.05] in preterm neo-nates, and showed a significant negative correlation with plasma ascorbic acid and vitamin C to ceruloplasmin ratio. The plasma antioxidant activity was significantly decreased in died preterm infants than survived preterm infants [P<0.05]. There was a significant high [P<0.05] plasma vitamin C in preterm neonates compared to full term neonates and also there was a significant high [P<0.05] vitamin C in died preterm neonates in comparison to survivors. There was a significant low [P<0.05] plasma ceruloplasmin in preterm neonates compared to full term neonates, but there was non significant difference in plasma ceruloplasmin between died and survived preterm neonates. Thus we concluded that plasma antioxidant activity at birth is a significant predictor of neonatal mortality. Some preterm neonates are born with low ceraloplasmin and high vitamin C concentration, the high vitamin C concentration may modulate theferroxidase activity of plasma cerulopasmin which may inhibit the antioxidant activity of plasma. This effect may be an important factor in the mortality of preterm neonates