The Impact of the Delivery Method on Oxidative Stress in Neonates: A Cross-Sectional Study

Abstract

Background/Objectives: Oxidative stress is a factor that may adversely affect the development of the foetus, the course of labour, and newborn health. This study aimed to determine the association between the labour method, oxidative stress parameters, and neonatal condition. Methods: The study material was umbilical cord blood from newborns delivered vaginally (n = 60) or by caesarean section (n = 108). The total antioxidant status (TAS), superoxide dismutase activity (SOD), glutathione peroxidase activity (GPx), and glutathione reductase activity (GR) were determined using colorimetric methods. The concentration of the chemical elements (Zn, Cu, Mn) was estimated, using atomic absorption spectrometry (ASA). Results: The SOD activity was significantly lower in newborns with an Apgar score below 10 at the 5th minute of life compared to newborns with the highest Apgar points (p = 0.041). In neonates delivered by caesarean section (CS), but not vaginally born (VB) neonates, the SOD activity was significantly lower in newborns with Apgar scores less than 10 at the 5th minute of life compared to newborns with the maximum number of Apgar points (p = 0.02). Conclusions: The reduced SOD activity in the umbilical cord blood of newborns with Apgar scores less than 10 could be related to increased oxidative stress during labour. Bupivacaine-induced oxidative stress seems to be the cause of SOD downregulation in caesarean-delivered newborns. The observed SOD downregulation in neonates delivered by CS and with a decreased Apgar score requires confirmation based on a larger cohort of neonates.

Keywords: Apgar score; antioxidant enzymes; bupivacaine; caesarean section; cord blood; oxidative stress; vaginal delivery.

Figure 1

Principal Component Analysis based on oxidative stress markers in newborns and the Apgar score at the 1st minute of life; (a) score plot of cases and grouping of variable ellipses. Each dot represents a case, and the shade of the colour reflects the variable’s value. (b) Variable correlation plots. Variables positively correlated are collected together, and those negatively correlated are located on opposite sides of the plot. The distance between the variables and the origin reflects the quality of the variables (marked as cos2), and the colour reflects the value of the variables.