Obstetric anal sphincter injury risk reduction: a retrospective observational analysis

Vathanan, V and Ashokkumar, Oliparambil and McAree, Trixie (2014) Obstetric anal sphincter injury risk reduction: a retrospective observational analysis. Journal of Perinatal Medicine, 42 (6). pp. 761-767. ISSN 1619-3997

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Objective: To identify the risks of sustaining obstetric anal sphincter injury (OASI) during childbirth.
Methods: Data were analysed from 12,612 vaginal deliveries recorded at Northwick Park District General Hospital, London, from 1 January 2006 to 30 November 2009.
Results: A total of 85.6% were spontaneous deliveries and 14.2% were instrument deliveries. The majority (64.5%) sustained some form of perineal damage, 3.7% being OASI. Logistic regression analyses revealed the risk factors for OASI to be Asian ethnicity [odds ratio (OR) 4.798, 95% confidence interval (CI) 2.998–7.679], a maternal age of > 40 years (OR 2.722, 95% CI 1.315–5.636), higher foetal birth weight ( > 4500 g; OR 6.228, 95% CI 2.695–14.392),lower parity (para 0; OR 16.803, 95% CI 7.697–36.685), and instrumental delivery. Forceps delivery posed the greatest risk (OR 8.4, 95% CI 5.822–12.151). Not having an episiotomy increased the risk of OASI by five times compared with having one.
Conclusions: Risk factors for OASI include maternal age > 40 years, higher foetal birth weight, lower parity, instrumental delivery, and Asian ethnicity. Mediolateral episiotomy appears to reduce the risk of OASI. Specific variables have been identified for incorporation into a risk-reduction strategy that could be introduced antenatally to evaluate and assess OASI risk.

Item Type: Article
Identification Number: https://doi.org/10.1515/jpm-2013-0269
November 2014Published
6 March 2014Accepted
2 October 2013Submitted
Uncontrolled Keywords: Episiotomy; instrumental delivery; obstetric anal sphincter injury; perineal trauma
Subjects: CAH01 - medicine and dentistry > CAH01-01 - medicine and dentistry > CAH01-01-01 - medical sciences (non-specific)
Divisions: Faculty of Health, Education and Life Sciences > Centre for Social Care, Health and Related Research (C-SHARR)
Depositing User: Trixie Mcaree
Date Deposited: 13 Nov 2019 09:01
Last Modified: 03 Mar 2022 17:15
URI: https://www.open-access.bcu.ac.uk/id/eprint/8412

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