Predictive inability of cord zinc, magnesium and copper levels on the development of benign hyperbilirubinemia in the newborn

Cord blood zinc status effects on pregnancy outcomes and its relation with maternal serum zinc levels: a systematic review and meta-analysis

BACKGROUND

The association between maternal and cord blood zinc level and pregnancy outcomes remains uncertain. The present study aims to assess whether maternal blood zinc level represents cord blood zinc level correctly.

METHODS

In this meta-analysis, systematic search was performed in PubMed, Web of Science, and Scopus databases for relevant available English articles which included mean and standard deviation values of cord blood zinc level up to April 2019. For the assessment of the relation between cord blood zinc level and pregnancy outcomes, the pooled standard mean difference with 95% confidence interval (CI) was used and 23 studies were analyzed.

RESULTS

Cumulative analysis showed that cord blood zinc level was found significantly decreased in pregnancies with complications compared with healthy pregnancy controls [REM: P = 0.0007, mean difference - 7.9 (- 12.48, - 3.31)]. For further analysis, maternal serum zinc level status was determined from same studies to compare with cord blood levels and subgroups were detected as "Preterm", "Preeclampsia", "Small for gestational age/Intrauterine growth restriction and Low birth weight". It was observed that cord blood zinc levels in subgroup analysis were also decreased and/or tend to be decreased compared to healthy pregnancies, except for preeclampsia subgroup. Also, a correlation was seen between cord blood and maternal blood zinc level status (R = 0.4365, 95% CI - 0.530, 0.756; P = 0.0351).

CONCLUSION

It was thought that cord blood zinc level might tend to decrease more than maternal serum zinc level in the pathological conditions during pregnancies.

Can Exchange Transfusion Normalize Serum Levels of Copper, Zinc, and Magnesium in Severe Neonatal Hyperbilirubinemia?

BACKGROUND

Neonatal hyperbilirubinemia is a frequently encountered problem. Erythrocytes, especially reticulocytes are rich in copper (Cu) and magnesium (Mg) so its serum levels increase after hemolysis. Zinc (Zn) plays an important role in synthesis of some enzymes included in the bilirubin metabolism and may cause hemolysis. Exchange transfusion is the main treatment for severe neonatal hyperbilirubinemia but can exchange transfusion affect the previous trace elements.

MATERIALS AND METHODS

We measured Cu, Zn, and Mg serum levels in full-term neonates admitted to neonatal intensive care unit of Minia University hospital with severe indirect hyperbilirubinemia before and after exchange transfusion.

RESULTS

There were significant higher serum Cu and Mg and lower Zn serum levels in neonates with hyperbilirubinemia than controls and their levels were significantly normalized after exchange transfusion. Significant positive correlations between the total bilirubin levels and hemoglobin, Cu and Mg serum levels and significant negative correlations with Zn levels were present. There were no significant correlations between maternal and neonatal serum levels of any of them.

CONCLUSIONS

Exchange transfusion can normalize the significant higher Cu and Mg and lower Zn serum levels in neonates with severe indirect hyperbilirubinemia which were not related to their maternal serum levels.

Magnesium supplementation affects metabolic status and pregnancy outcomes in gestational diabetes: a randomized, double-blind, placebo-controlled trial

BACKGROUND

To our knowledge, prior research has not examined the effects of magnesium supplementation on metabolic status and pregnancy outcomes in maternal-child dyads affected by gestational diabetes (GDM).

OBJECTIVE

This study was designed to assess the effects of magnesium supplementation on metabolic status and pregnancy outcomes in magnesium-deficient pregnant women with GDM.

DESIGN

A randomized, double-blind, placebo-controlled clinical trial was performed in 70 women with GDM. Patients were randomly assigned to receive either 250 mg magnesium oxide (n = 35) or a placebo (n = 35) for 6 wk. Fasting blood samples were taken at baseline and after a 6-wk intervention.

RESULTS

The change in serum magnesium concentration was greater in women consuming magnesium than in the placebo group (+0.06 ± 0.3 vs. -0.1 ± 0.3 mg/dL, P = 0.02). However, after controlling for baseline magnesium concentrations, the changes in serum magnesium concentrations were not significantly different between the groups. Changes in fasting plasma glucose (-9.7 ± 10.1 vs. +1.8 ± 8.1 mg/dL, P < 0.001), serum insulin concentration (-2.1 ± 6.5 vs. +5.7 ± 10.7 μIU/mL, P = 0.001), homeostasis model of assessment-estimated insulin resistance (-0.5 ± 1.3 vs. +1.4 ± 2.3, P < 0.001), homeostasis model of assessment-estimated β-cell function (-4.0 ± 28.7 vs. +22.0 ± 43.8, P = 0.006), and the quantitative insulin sensitivity check index (+0.004 ± 0.021 vs. -0.012 ± 0.015, P = 0.005) in supplemented women were significantly different from those in women in the placebo group. Changes in serum triglycerides (+2.1 ± 63.0 vs. +38.9 ± 37.5 mg/dL, P = 0.005), high sensitivity C-reactive protein (-432.8 ± 2521.0 vs. +783.2 ± 2470.1 ng/mL, P = 0.03), and plasma malondialdehyde concentrations (-0.5 ± 1.6 vs. +0.3 ± 1.2 μmol/L, P = 0.01) were significantly different between the supplemented women and placebo group. Magnesium supplementation resulted in a lower incidence of newborn hyperbilirubinemia (8.8% vs. 29.4%, P = 0.03) and newborn hospitalization (5.9% vs. 26.5%, P = 0.02).

CONCLUSION

Magnesium supplementation among women with GDM had beneficial effects on metabolic status and pregnancy outcomes. This trial was registered at www.irct.ir as IRCT201503055623N39.

Maternal micronutrients and fetal outcome

Maternal micronutrient deficiency has been related to adverse fetal effects. It is believed that micronutrient supplementation during pregnancy may improve fetal and neonatal outcome. Despite biological plausibility, the evidence base for individual micronutrient benefit on neonatal morbidity, mortality, growth and development is patchy and often contradictory, except for the role of folic acid in prevention of neural tube defects. Single micronutrient supplementation interventions have not been shown to consistently affect size at birth or duration of gestation. Sound evidence is generally lacking that micronutrient supplementation can reduce infection-related adverse pregnancy outcomes. However, preliminary data suggests that antenatal zinc supplements may cause reduction in later diarrheal and infectious morbidity in infants. The evidence linking maternal micronutrient deficiency to children's cognitive and motor functioning also lacks a clear consensus except for iodine in endemic areas. There is a pressing need for good quality randomized controlled trials evaluating food based and multiple micronutrient interventions in pregnancy and preconceptually. Future studies should also evaluate the effect on body composition and metabolism along with the functional consequences.

Evaluation of plasma ionized magnesium levels in neonatal hyperbilirubinemia

Plasma levels of ionized magnesium (IMg) measured by ion-selective electrode were investigated in neonatal hyperbilirubinemia by comparing the newborns with (> or =205 microM) and without (<205 microM) significant hyperbilirubinemia (groups of severe and moderate hyperbilirubinemia, respectively). Serum bilirubin, plasma IMg, and ionized calcium (ICa) levels were determined in 165 healthy term newborns with nonhemolytic indirect hyperbilirubinemia during the first 10 d of life. Mean serum bilirubin, plasma IMg, and ICa levels were 200.1 +/- 126.5 microM, 0.54 +/- 0.12 mM, and 1.15 +/- 0.12 mM, respectively, in 165 newborns whose mean postnatal age was 156.1 +/- 46.5 h, and there was a significant positive correlation between the mean serum bilirubin and plasma IMg levels (r = 0.535, p < 0.001). Serum bilirubin levels (304.4 +/- 83.8 microM versus 94.1 +/- 54.7 microM) and plasma IMg levels (0.6 +/- 0.12 mM versus 0.49 +/- 0.1 mM) were significantly higher and plasma ICa levels (1.13 +/- 0.12 mM versus 1.18 +/- 0.12 mM) were significantly lower in the group of severe hyperbilirubinemia (n = 83) when compared with the group with moderate hyperbilirubinemia (n = 82). Seventeen of the 83 cases of severe hyperbilirubinemia had IMg levels above the normal range (> or =0.69 mM), whereas none of the 82 cases of moderate hyperbilirubinemia had elevated IMg levels. Fifteen of the 17 with high IMg levels had bilirubin levels >290 microM. Results of the present study suggest that increase in plasma IMg may be due to extracellular movement of Mg, a principally intracellular ion, resulting from generalized cellular injury including neurons and erythrocytes. Considering neuroprotective functions and beneficial effects of Mg ion in improving neurologic outcome, we also may speculate the possibility of a neuroprotective role or a compensatory mechanism in IMg increase against emerging toxicity risk of increasing serum bilirubin levels.

Micronutrient status during pregnancy and outcomes for newborn infants in developing countries

More than 9 million neonatal deaths occur each year, 98% of them in developing countries. Neonatal deaths account for two-thirds of deaths in infancy and 40% of deaths before age 5 y. The major direct causes of neonatal death are infections, preterm delivery and asphyxia. Important indirect causes include low birth weight and hypothermia. The present body of work on multiple micronutrient interventions is not sufficient for us to draw conclusions on their effects on neonatal well-being. Because studies have generally concentrated on single micronutrients and a range of outcomes, this paper reviews the findings for individual nutrients and then summarizes the situation. The evidence for the contribution of micronutrient deficiencies to perinatal mortality and duration of gestation is limited, and the evidence base for individual micronutrient effects on neonatal mortality and morbidity is patchy. To translate knowledge into policy, community evaluations of effect and an expanded evidence base that includes affordability, acceptability and scalability are also required. A balance between supply-side and demand-side interventions must be struck, with an emphasis on effect and sustainability. Among the key requirements are randomized, controlled community effectiveness trials of the effect of micronutrient supplementation in pregnancy on perinatal mortality and neurodevelopment, studies on improving adherence and studies on the relation between micronutrient deficiencies and sepsis and neonatal encephalopathy. It would also be helpful to look at mechanisms for bringing the periconceptional period within the ambit of trials.

Concentrations of copper, zinc and selenium in brain and kidney of second trimester fetuses and infants

The concentrations of copper (Cu), zinc (Zn) and selenium (Se) in the brain and kidneys of second trimester fetuses (abortion cases) and infants (deceased before three months of age) were determined. Concentrations of Cu in brain, 0.31-1.6 mg/kg wet weight, increased with age, and were, on the average, three times higher in the brains of infants than of fetuses. In kidneys, Cu concentrations ranged between 0.34 and 2.9 mg/kg, and increased with age after birth. Concentrations of Zn in the brain decreased significantly with age in the fetuses, from about 7 mg/kg at post-conceptional week 12 to less than 5 mg/kg at week 20, but increased again postnatally. In kidneys, Zn concentrations (12-37 mg/kg) increased in parallel with the increase in tissue density. Concentrations of Se in brain, 0.072-0.14 mg/kg, decreased with age in the fetuses, but increased with age postnatally. Kidney Se concentrations (0.16-0.55 mg/kg) did not change significantly with age during the fetal period, but increased about 2.5 times during the postnatal period. There was a significant association between the concentrations (on molar basis) of Zn and Cu in kidneys, but not in brain. There was no correlation between the concentrations of Cu, Zn or Se and those of mercury, cadmium and lead, previously determined in the same samples, with the exception of mercury and Se in kidneys.