Drusany Starič Kristina, Bukovec Petra, Jakopič Katja, Zdravevski Eftim, Trajkovik Vladimir, Lukanović Adolf
Division of Gynaecology and Obstetrics, University Medical Centre Ljubljana, Ljubljana, Slovenia.
Division of Gynaecology and Obstetrics, University Medical Centre Ljubljana, Ljubljana, Slovenia.
Eur J Obstet Gynecol Reprod Biol. 2017 Mar;210:196-200. doi: 10.1016/j.ejogrb.2016.12.029. Epub 2016 Dec 23.
The aim of the study was to identify primiparous pregnant women with a higher risk for obstetric anal sphincter injuries (OASIS) based on obstetric characteristics (risk factors).
In the retrospective case control study primiparous women were examined using endoanal ultrasonography (EUS) for OASIS identification 6-12 weeks after delivery. Obstetric characteristics for OASIS were collected from the mothers' medical records. The univariate analysis of maternal (age at delivery, maternal height, weight, BMI), infant (length, weight and head circumference) and birth (pregnancy duration, labour and delivery duration, episiotomy, vacuum extraction and oxytocin augmentation) risk factors, Pearson correlations and information gain were carried out. The cut-off values for the aforementioned risk factors divided the patients into groups with higher and lower risk of OASIS.
The data of 84 primiparous women with OASIS, and 58 without, were analysed. Those newborns born to women in the OASIS group were heavier (P<0.05), with the cut-off at 3420g (72% probability of OASIS), had a larger head circumference (P<0.001), cut-off at 36cm (84% probability of OASIS), and were longer (P<0.05), cut-off at 50.5cm (74% probability of OASIS). The maternal age and body mass index (BMI) were risk factors for OASIS (P<0.05 and P<0.05, respectively) with a probability of 83% in women younger than 27.5 years and a 78% probability if BMI was higher than 28kg/m. The incidence of OASIS was not higher in women with episiotomy or vacuum extraction, but it was higher in oxytocin augmentation (P<0.031).
The findings can assist in identification of pregnant women with a higher risk of OASIS who require special attention at delivery to prevent it. In high risk women EUS is indicated to identify and treat possible OASIS as early as possible in order to prevent anal incontinence.
本研究旨在根据产科特征（风险因素）识别初产妇发生产科肛门括约肌损伤（OASIS）风险较高的人群。
在这项回顾性病例对照研究中，对初产妇在产后6 - 12周使用经肛门超声检查（EUS）来识别OASIS。从母亲的病历中收集OASIS的产科特征。对产妇（分娩年龄、产妇身高、体重、体重指数）、婴儿（身长、体重和头围）及分娩（孕期、产程和分娩时长、会阴切开术、真空吸引术和催产素引产）的风险因素进行单因素分析、Pearson相关性分析和信息增益分析。上述风险因素的临界值将患者分为OASIS风险较高和较低的组。
分析了84例发生OASIS的初产妇和58例未发生OASIS的初产妇的数据。OASIS组产妇所生新生儿体重更重（P<0.05），临界值为3420g（发生OASIS的概率为72%），头围更大（P<0.001），临界值为36cm（发生OASIS的概率为84%），身长更长（P<0.05），临界值为50.5cm（发生OASIS的概率为74%）。产妇年龄和体重指数（BMI）是OASIS的风险因素（分别为P<0.05和P<0.05），年龄小于27.5岁的女性发生概率为83%，BMI高于28kg/m²时发生概率为78%。会阴切开术或真空吸引术产妇的OASIS发生率并不更高，但催产素引产的产妇发生率更高（P<0.031）。
这些发现有助于识别发生OASIS风险较高的孕妇，她们在分娩时需要特别关注以预防该情况。对于高危女性，建议使用EUS尽早识别并治疗可能的OASIS，以预防肛门失禁。
