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

## TL;DR

This study found that newborns delivered by caesarean section with lower Apgar scores had reduced antioxidant activity, possibly due to oxidative stress.

## Contribution

The study identifies a link between caesarean delivery, lower Apgar scores, and reduced superoxide dismutase activity in neonates.

## Key findings

- SOD activity was significantly lower in newborns with Apgar scores below 10 at 5 minutes of life.
- In caesarean-delivered newborns, lower SOD activity was associated with lower Apgar scores.
- Bupivacaine-induced oxidative stress may explain reduced SOD activity in caesarean-delivered neonates.

## 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.