The association of maternal social factors and antenatal care with cord serum zinc in full – term neonates

Abstract

Zinc is a crucial micronutrient in early childhood survival and the development of innate and acquired immunity. The objective is to determine the relationship between of maternal social class and antenatal care to serum zinc level in newborns in a tertiary and a rural hospital. It is prospective study using questionnaires on consecutive mothers with normal pregnancy(excluding sepsis and chronic illneses) and cord serum level of Zinc estimation in newborns using flame atomic absorption spectrophotometry. There were 106 mothers and neonates; were made up of 57 females and 49 males. The ages of the mother ranged between 21 years to 39 years, with a mean of 26 years; while the gestational age of the neonates ranged between 30 weeks and 45 weeks with a mean of 37.3. The range of the serum Zinc was 0.14μg/L – 0.92μg/L, with a mean of 0.64μg/L (SD=0.17) and median value of 0.63μg/L. The
social classes of the mothers were low 66, middle 23 and high 17 with mean neonatal serum zinc of 0.62μg/L, 0.68μg/L and 0.72μg/L. The mean serum Zinc in 17/86 neonates of mothers with inadequate tetanus vaccination was 0.53μg/L, (below the median value) compared to 0.66μg/L in 89/106 neonates of mothers with complete vaccination. The serum zinc in the neonates of mothers <25 years of age was 0.68μg/L compared to 0.61μg/L in the neonates of mothers >25years. Fever in pregnancy was seen in 31/106; with mean neonatal serum Zinc of 0.63μg/L compared with those without fever 0.65μg/L. There were 94 neonates with normal weight (>2.5kg) and 12 low birth weight (<2.5kg) with mean serum Zinc of 0.69μg/L and 0.66μg/L respectively. Antenatal care was complete in 81 and incomplete in 25 with mean neonatal serum Zinc of 0.66μg/L and 0.56μg/L respectively. Univariate analysis revealed significant correlation between the mean serum Zinc and the socioeconomic class (P = 0.022), but there was no correlation with maternal age (P=0.327), sex (P=0.566), gestational age (P=0.100), birth weight (P=0.365), vaccination (P=0.954), malaria fever (P=0.875) and antenatal care (P=0.97), We concluded that low social status of the mothers and inadequate vaccination in pregnancy were major factors associated with low neonatal serum zinc. The control of these factors may impact on optimal neonatal nutrition. (Afr. J. Biomed. Res. 11: 297 - 303)

Key word: neonates, serum zinc, maternal social classes, antenatal care, association