Umbilical Cord Zinc Levels and Neonatal Anthropometric Measures: A Cross-Sectional Study in Iran

Background: Zinc (Zn) is one of the trace elements in the body that, despite its low level, plays important roles in molecular and cellular activities. A few investigations have assessed the correlations between cord blood Zn levels and neonatal anthropometric measures; however, the results are conflicting. Objectives: The purpose of the present study was to investigate the relationships between the Zn level in the umbilical cord blood and the birth weight, height, and head circumference of term newborns. Methods: A cross-sectional study was conducted on full-term newborns in Tehran, Iran, in 2021. Neonates’ Zn levels in umbilical cord blood were evaluated. Data related to perinatal and neonatal variables such as the number of pregnancies (gravida), birth height, weight, and head circumference were recorded, and their relationships with umbilical cord Zn levels were assessed. P-values < 0.05 were considered statistically significant. Results: One hundred mothers with a mean age of 30.792 ± 5.908 years and a parity of 2.693 ± 1.181 were included. Of all the newborns, 68% were boys, and 2% had low birth weight. The mean level of cord blood Zn was 107.703 ± 27.843 µg/dL. Evaluating the correlations between cord blood Zn levels and maternal and neonatal qualitative variables, data analysis showed no relationships between Zn levels and neonatal sex (P = 0.70), low birth weight (P = 0.87), and maternal underlying disease (P = 0.49). Data analysis regarding correlations between quantitative variables also showed no significant correlations between cord blood Zn levels and birth weight (P = 0.466), height (P = 0.466), and head circumference (P = 0.925). Conclusions: Although adequate Zn levels were observed in all neonates, these levels did not significantly influence neonatal anthropometric measures or immediate health indicators. Further studies with larger sample sizes are recommended to provide more comparative data, particularly in relation to long-term growth outcomes.