# Effects of Lateral Positions in Second‐Stage Labour on Maternal and Neonatal Outcomes: An Observational Study Using Propensity Score Matching Analysis

## TL;DR

This study finds that using lateral positions during childbirth can reduce perineal tears in first-time mothers but may increase blood loss and prolong labor.

## Contribution

The study provides new evidence on the benefits and risks of lateral positions during labor, particularly for primiparous women.

## Key findings

- Lateral positions reduced episiotomy use and moderate perineal tears in first-time mothers.
- Lateral positions increased postpartum blood loss and prolonged labor for first-time mothers.
- Apgar scores and severe perineal tears were rare across both positions.

## Abstract

This study aims to examine the effects of lateral positions during the second stage of labour on maternal and neonatal outcomes.

A prospective observational study was conducted in three Chinese hospitals from June to November 2020.

Eligible women were divided into groups based on their use of lithotomy or lateral positions during the second stage of labour. Propensity score matching (PSM) was employed to assess the effects of lateral positions on maternal outcomes (perineal tears, episiotomy use, postpartum blood loss, duration of the second stage of labour, and mode of birth) and neonatal outcomes (Apgar scores at one and 5 min postpartum).

After PSM matching, lateral positions were associated with a 21% reduced risk of episiotomy use among primiparous women. Primiparous women adopting lateral positions also had significantly reduced risks of moderate perineal tears. There were no significant differences in the duration of the second stage of labour, mode of birth or rates of blood loss over 500 mL at 2 h postpartum. However, lateral positions increased the duration of the second stage of labour by 10 min among primiparous women who adopted lateral positions in this study, and both primiparous and parous women using lateral positions had greater postpartum blood loss. Cases of Apgar scores less than seven and severe perineal tears were rare.

This prospective observational study indicates that lateral positions during the second stage of labour may offer protective benefits for the perineum among primiparous women. However, their use requires careful clinical judgement, as they may not be suitable for primiparous women experiencing slower labour progress, and additional attention should be given for monitoring postpartum blood loss, regardless of parity.

What is already known?
Maternal positions during the second stage of labour are closely associated with maternal and neonatal outcomes.In recent years, the adoption of lateral positions during this stage has gained popularity in China and could play a crucial role in promoting safe vaginal births. Nevertheless, the effects of these positions on maternal and neonatal outcomes remain uncertain.

Maternal positions during the second stage of labour are closely associated with maternal and neonatal outcomes.

In recent years, the adoption of lateral positions during this stage has gained popularity in China and could play a crucial role in promoting safe vaginal births. Nevertheless, the effects of these positions on maternal and neonatal outcomes remain uncertain.

What this paper adds?
Lateral positions during the second stage of labour may prevent perineal tears, with greater protective impacts observed among primiparous women who actually adopted lateral positions in clinical practice.Lateral positions may increase the amount of postpartum blood loss, regardless of parity.Lateral positions may prolong the second stage of labour among primiparous women.

Lateral positions during the second stage of labour may prevent perineal tears, with greater protective impacts observed among primiparous women who actually adopted lateral positions in clinical practice.

Lateral positions may increase the amount of postpartum blood loss, regardless of parity.

Lateral positions may prolong the second stage of labour among primiparous women.

What are the implications of this study?
Findings from this study suggest that while lateral positions during the second stage of labor may offer benefits, such as reducing perineal tears, they also carry potential risks, including increased postpartum blood loss and a longer second stage of labour for primiparous women.Providing individualized care that considers a woman's parity and preferences is essential for optimizing maternal and neonatal outcomes.

Findings from this study suggest that while lateral positions during the second stage of labor may offer benefits, such as reducing perineal tears, they also carry potential risks, including increased postpartum blood loss and a longer second stage of labour for primiparous women.

Providing individualized care that considers a woman's parity and preferences is essential for optimizing maternal and neonatal outcomes.