Research Protocol Volume 15 Issue 1 - 2026

Episiotomy Rate and Obstetric Anal Sphincter Injuries among Vaginal Deliveries: A Retrospective Cohort at a Teaching Hospital, Sri Lanka

Walawe Nayaka S*

Post Graduate, Institute of Medicine, University of Colombo, Sri Lanka

*Corresponding Author: Walawe Nayaka S, Post Graduate, Institute of Medicine, University of Colombo, Sri Lanka.
Received: December 22, 2025; Published: January 03, 2026



Background: Routine episiotomy remains common in Sri Lanka, despite evolving guidelines advocating selective use. This study assesses episiotomy prevalence, complications, and the incidence of obstetric anal sphincter injuries (OASIS) among 200 vaginal deliveries.

Methods: Retrospective review of labour-room records from January 2020 backwards. Data captured: maternal age, parity, birthweight, episiotomy status, documented OASIS, and immediate episiotomy outcomes. Rates stratified by parity and birthweight; complications recorded included infection, hematoma, re-suturing, and theatre repair.

Results: Episiotomy rate was 99% overall (100% in primiparas; ~98% in multiparas). Across all birth weights episiotomy exceeded 96%. No OASIS was documented. Complications included one theatre repair (0.5%), five infections (2.5%), one hematoma (0.5%), and one re-suturing (0.5%). Fourteen instrumental deliveries-all with episiotomy (100%).

Conclusion: Episiotomy was nearly universal regardless of risk profile; benefits in preventing OASIS could not be assessed. Routine use exposes women to unnecessary morbidity. Policies should emphasize selective use, technique standardization, and adherence to evidence-based guidelines.

 Keywords: Obstetric Anal Sphincter Injuries (OASIS); Vaginal Deliveries; Episiotomy

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Walawe Nayaka S. “Episiotomy Rate and Obstetric Anal Sphincter Injuries among Vaginal Deliveries: A Retrospective Cohort at a Teaching Hospital, Sri Lanka”. EC Gynaecology  15.1 (2026): 01-05.