Nager C W, Helliwell J P
Department of Reproductive Medicine, The University of California, San Diego Medical Center, 92103-8433, USA.
Am J Obstet Gynecol. 2001 Aug;185(2):444-50. doi: 10.1067/mob.2001.116095.
The aim of this study was to determine the clinical factors that contribute to posterior perineal laceration length.
A prospective observational study was performed in 80 consenting, mostly primiparous women with term pregnancies. Posterior perineal lacerations were measured immediately after delivery. Numerous maternal, fetal, and operator variables were evaluated against laceration length and degree of tear. Univariate and multivariate regression analyses were performed to evaluate laceration length and parametric clinical variables. Nonparametric clinical variables were evaluated against laceration length by the Mann-Whitney U test.
A multivariate stepwise linear regression equation revealed that episiotomy adds nearly 3 cm to perineal lacerations. Tear length was highly associated with the degree of tear (R = 0.86, R(2) = 0.73) and the risk of recognized anal sphincter disruption. None of 35 patients without an episiotomy had a recognized anal sphincter disruption, but 6 of 27 patients with an episiotomy did (P <.001). Body mass index was the only maternal or fetal variable that showed even a slight correlation with laceration length (R = 0.30, P =.04).
Episiotomy is the overriding determinant of perineal laceration length and recognized anal sphincter disruption.
本研究旨在确定导致会阴后位撕裂长度的临床因素。
对80名足月妊娠、大多为初产妇且同意参与研究的女性进行了一项前瞻性观察研究。分娩后立即测量会阴后位撕裂情况。针对撕裂长度和撕裂程度评估了众多母体、胎儿及手术操作者的变量。进行单因素和多因素回归分析以评估撕裂长度和参数化临床变量。通过曼-惠特尼U检验针对撕裂长度评估非参数临床变量。
多因素逐步线性回归方程显示，会阴切开术会使会阴撕裂长度增加近3厘米。撕裂长度与撕裂程度高度相关（R = 0.86，R² = 0.73）以及与公认的肛门括约肌断裂风险相关。35名未行会阴切开术的患者中无一例出现公认的肛门括约肌断裂，但27名行会阴切开术的患者中有6例出现（P <.001）。体重指数是唯一与撕裂长度有轻微相关性的母体或胎儿变量（R = 0.30，P =.04）。
会阴切开术是会阴撕裂长度和公认的肛门括约肌断裂的首要决定因素。
