Zinc and copper levels in low birth weight deliveries in Medani Hospital, Sudan

Abstract

BackgroundLow birth weight (LBW) is a worldwide health problem, especially in developing countries. We conducted a case–control study at Medani Hospital, Sudan. Cases were women who delivered a LBW (<2500 g) newborn and consecutive women who delivered a normal weight (>2500 g) newborn were controls. Questionnaires were used to collect clinical data. Zinc and copper levels were measured by an atomic absorption spectrophotometer.FindingsThe two groups (50 in each arm) were well matched in their basic characteristics. Median (25–75th interquartile range) maternal zinc (62.9 [36.3–96.8] vs. 96.2 [84.6–125.7] μg/dl; P <0.001) and copper (81.6 [23.7–167.5] vs. 139.8 [31.9–186.2] μg/dl; P = 0.04) levels were significantly lower in cases than in controls. Cord copper levels in cases were significantly lower than those in controls (108 [55.1–157.9] vs. 147.5 [84.5–185.2] μg/dl; P = 0.02). There were significant direct correlations between birth weight and maternal copper levels and maternal and cord zinc levels.ConclusionsMaternal zinc and copper levels, as well as cord copper levels, are lower in LBW newborns than in those with normal weight.

Association between Maternal Zinc Status, Dietary Zinc Intake and Pregnancy Complications: A Systematic Review

“…Conversely, two other studies reported serum zinc to be 40–172 µg/L higher in women who gave birth to a LBW infant compared to those who gave birth to an appropriate weight infant [60,66]. A further four studies, also based on women from India, reported no association between circulating zinc levels and birthweight [62,63,64,69] and this was also reported in two studies of Turkish women [58,65]. However, univariate analysis and small sample size in these studies may not provide an accurate assessment of the effects of maternal circulating zinc and birthweight.…”

“…The association between maternal circulating zinc and birthweight was assessed in 14 studies based on women where inadequate dietary zinc intake was predicted to affect ≥17% of the population [57,58,59,60,61,62,63,64,65,66,67,68,69], of which 7 reported a significant association (Table 1) [57,59,60,61,66,67,68]. All three of the studies based on women from Africa reported serum/plasma zinc on average 72–333 µg/L lower in women who gave birth to a LBW infant compared to those who gave birth to an appropriate weight infant [57,59,67].…”

Effects of Environmental Exposures on Fetal and Childhood Growth Trajectories

“…A clinical trial reported that daily Zn supplementation in women with relatively low plasma Zn concentrations at 19 weeks gestation is associated with greater infant birth weights and head circumferences. 112 Conversely, studies using blood samples collected at birth or in late pregnancy have produced inconsistent results, with eight studies 78,114–119 showing no association and three studies 120–122 observing an increased risk between maternal serum Zn levels and risk of delivering LBW infants.…”

Birth Weight in Relation to Maternal Blood Levels of Selected Elements in Slovenian Populations: A Cross-sectional Study

“…Studies have shown significant direct correlations between birth weight and maternal levels of zinc (Zn) and copper (Cu) in serum [21]. As for manganese (Mn), it has been suggested that Mn levels in maternal whole blood influence birth weight [22,23], while the absence of a correlation between birth weight and Mn, Cu, Zn and selenium (Se) in maternal blood has also been reported [24][25][26].…”