Umbilical Serum Copper Status and Neonatal Birth Outcomes: a Prospective Cohort Study

Abstract

Our study aimed to assess the distribution of copper (Cu) in umbilical cord serum and estimated the association between umbilical serum Cu status and neonatal birth outcomes in a Chinese population. Through the Ma'anShan Birth Cohort Study, 2689 maternal-singleton pairs with detailed birth records and available serum samples were identified. The tertile levels of ln-transformed Cu were used to define low, medium, and high levels for serum Cu. The median for umbilical cord serum Cu was 298.2 μg/L with a range of 123.1-699.6 μg/L in this study population. Our study found a positive association between the concentration of serum Cu in the umbilical cord and the duration of gestation. Compared with medium Cu levels, we found that infants with low Cu levels had a significant higher risk of preterm birth (OR = 5.06, 95% CI 2.74, 9.34) and early-term birth (OR = 1.36, 95% CI 1.10, 1.69) in the crude model. We also found that infants with high Cu levels had a significant higher risk of late- or post-term birth (OR = 1.47, 95% CI 1.11, 1.95). A significant higher risk of preterm, early-term, and late- or post-term birth still remained, even after adjustment for potential confounding factors. Our findings suggested that both Cu deficiency and Cu overload had an adverse effect on neonatal birth outcomes.

Maternal Serum Concentrations of Selenium, Copper, and Zinc during Pregnancy Are Associated with Risk of Spontaneous Preterm Birth: A Case-Control Study from Malawi

“…Very little information was found in the literature on the maternal serum concentrations of the trace elements selenium, copper, and zinc in pregnancy and their associations with spontaneous preterm birth in the African region. Comparing with researches from other regions, some studies have found maternal concentrations of these trace elements to be associated with preterm birth, while others have reported no associations [20,24,[35][36][37][38][39]. In this study, higher selenium concentrations were observed in the maternal serum of preterm birth, but this was not significant.…”

“…Copper is an essential cofactor for numerous enzymes involved in various biological processes. The effect of maternal copper concentration is not well understood with some studies suggesting increased preterm birth with copper deficiency [20][21][22][23] and others reporting no association [24,25]. Zinc is a crucial component of many metalloenzymes participating in protein and carbohydrate metabolism, nucleic acid synthesis, and antioxidant functions through the Cu/Zn superoxide dismutase [26].…”

Maternal Serum Concentrations of Selenium, Copper and Zinc during Pregnancy are associated with Risk of Spontaneous Preterm Birth: A case-control study from Malawi

“…Very little information was found in the literature on the maternal serum concentrations of the trace elements selenium, copper and zinc in pregnancy and their associations with spontaneous preterm birth in the African region. Comparing with researches from other regions some studies have found maternal concentrations of these trace elements to be associated with preterm birth, while others have reported no associations [21], [25], [36]- [40]. In this study, higher selenium concentrations were observed in maternal serum of preterm birth, but this was not significant.…”

“…Spontaneous preterm birth reduces the pregnancy duration with resultant increased maternal serum concentrations and reduced fetal hepatic stores. Clinical research indicate that serum concentrations of selenium, copper, and zinc are higher in term infants than preterm infants [21]- [24], [44]- [46]. Consequently, with adequate nutrition, serum concentrations of selenium, copper and zinc would be expected to be higher in serum of women delivering preterm as there is reduced time for the mother to pass these trace elements to placenta and fetus.…”

“…Copper is an essential cofactor for numerous enzymes involved in various biological processes. The effect of maternal copper concentration is not well understood with some studies suggesting increased preterm birth with copper deficiency [21]- [24] and others reporting no association [25], [26]. Zinc is a crucial component of many metalloenzymes participating in protein and carbohydrate metabolism, nucleic acid synthesis and antioxidants functions through Cu/Zn superoxide dismutase [27].…”