Richter Holly E, Brumfield Cynthia G, Cliver Suzanne P, Burgio Kathryn L, Neely Cherry L, Varner R Edward
Division of Medical and Surgical Gynecology, Department of Obstetrics and Gynecology, University of Alabama at Birmingham, 35249-7333, USA.
Am J Obstet Gynecol. 2002 Nov;187(5):1194-8. doi: 10.1067/mob.2002.126977.
This study was conducted to identify obstetric risk factors for anal sphincter tear in primiparous patients, patients with a previous cesarean delivery (VBAC), and patients with a previous vaginal delivery (PVD).
An obstetrics automated record system was accessed to retrospectively review records of all singleton vaginal deliveries at greater than 36 weeks' gestation (excluding breech and stillbirth) from 1995 through 2000 (n = 10,928). A number of potential risk factors for anal sphincter tear (third- and fourth-degree episiotomy extensions and lacerations) were tested with use of multivariate logistic regression analysis.
The risk of anal sphincter tear was significantly increased with primiparity (relative risk [RR] 4.08) and VBAC (RR 5.46) compared with PVD, birth weight greater than 4000 g (RR 2.41), forceps delivery (RR 6.00), vacuum delivery (RR 2.18), shoulder dystocia (RR 3.28), and episiotomy (RR 2.59).
Efforts to prevent anal sphincter tear might include reconsideration of modifiable risk factors such as episiotomy, operative vaginal delivery, and VBAC.
本研究旨在确定初产妇、有剖宫产史（阴道试产）的患者以及有经阴道分娩史的患者发生肛门括约肌撕裂的产科危险因素。
使用产科自动记录系统，回顾性分析1995年至2000年所有孕周大于36周的单胎阴道分娩记录（不包括臀位和死产）（n = 10928）。采用多因素逻辑回归分析对肛门括约肌撕裂（会阴Ⅲ度和Ⅳ度裂伤）的一些潜在危险因素进行检验。
与经阴道分娩史的患者相比，初产妇（相对危险度[RR] 4.08）和有剖宫产史（阴道试产）的患者（RR 5.46）发生肛门括约肌撕裂的风险显著增加，出生体重超过4000 g（RR 2.41）、产钳助产（RR 6.00）、真空吸引助产（RR 2.18）、肩难产（RR 3.28）以及会阴切开术（RR 2.59）也会增加风险。
预防肛门括约肌撕裂的措施可能包括重新考虑一些可改变的危险因素，如会阴切开术、阴道助产以及有剖宫产史（阴道试产）。
