A ten-year evaluation of the incidence of obstetric anal sphincter injury with a reduced episiotomy rate

INTRODUCTION: The role of episiotomy in preventing obstetric anal sphincter injury (OASIS) remains controversial. Liberal use of episiotomy has been reduced locally. This study aimed to review the incidence of OASIS in our unit over the past decade given the reduced episiotomy rate. METHODS: A retrospective study was conducted in a single tertiary obstetrics and gynaecology unit. All singleton vaginal deliveries, including normal and instrumental deliveries, between 2012 and 2021 were included. Data were retrieved from the hospital electronic delivery database between July 2022 and June 2023. The degree of OASIS was assessed using the Abdul Sultan classification. RESULTS: In total, 43 732 deliveries were included. The episiotomy rate decreased from 62.8% in 2012 to 44.7% in 2021 (P