Vathanan Veluppillai, Ashokkumar Oliparambil, McAree Trixie
J Perinat Med. 2014 Nov;42(6):761-7. doi: 10.1515/jpm-2013-0269.
To identify the risks of sustaining obstetric anal sphincter injury (OASI) during childbirth.
Data were analysed from 12,612 vaginal deliveries recorded at Northwick Park District General Hospital, London, from 1 January 2006 to 30 November 2009.
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.
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.
确定分娩期间发生产科肛门括约肌损伤（OASI）的风险。
分析了2006年1月1日至2009年11月30日在伦敦诺斯威克公园综合医院记录的12612例阴道分娩的数据。
总共85.6%为自然分娩，14.2%为器械助产。大多数（64.5%）发生了某种形式的会阴损伤，3.7%为OASI。逻辑回归分析显示，OASI的风险因素包括亚洲种族[比值比（OR）4.798，95%置信区间（CI）2.998 - 7.679]、产妇年龄>40岁（OR 2.722，95%CI 1.315 - 5.636）、胎儿出生体重较高（>4500 g；OR 6.228，95%CI 2.695 - 14.392）、低产次（初产妇；OR 16.803，95%CI 7.697 - 36.685）以及器械助产。产钳助产风险最大（OR 8.4，95%CI 5.822 - 12.151）。未行会阴侧切术相比行会阴侧切术使OASI风险增加了五倍。
OASI的风险因素包括产妇年龄>40岁、胎儿出生体重较高、低产次、器械助产以及亚洲种族。会阴中侧切术似乎可降低OASI风险。已确定了特定变量，可纳入产前引入的降低风险策略中，以评估和评估OASI风险。
