title: Prior third- or fourth-degree perineal tears and recurrence risks.
abstract: OBJECTIVE
  The objective of the present study is to determine the recurrence risk of a third-degree (into the anal sphincter) or a fourth-degree (into the rectum) perineal tear in women with a prior extensive laceration.
  
  
  METHODS
  Data were gathered from our computerized perinatal database between January 1990 and December 1994. Women who had two consecutive singleton deliveries were chosen as subjects.
  
  
  RESULTS
  The rate of an extensive perineal laceration was greater if a tear had occurred in a previous pregnancy (19 of 178 cases, 10.7% vs. 56% of 1563 cases, 3.6%, odds ratio 3.4. A 95% confidence interval: 1.8-6.4; p < 0.0001). A prior tear remained a risk factor after controlling for other variables (epidural analgesia, episiotomy, oxytocin use, operative vaginal delivery, fetal macrosomia).
  
  
  CONCLUSIONS
  A prior third-degree or fourth-degree perineal tear is associated with a 3.4-fold increased risk of a recurrent severe obstetrical laceration.
authors: Department of Obstetrics and Gynecology, The University of Oklahoma, Oklahoma City, USA.
authors: T N
authors: TN
authors: Payne
authors: J C
authors: JC
authors: Carey
authors: W F
authors: WF
authors: Rayburn
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008499:Medical Records; D007744:Obstetric Labor Complications / Q000453:epidemiology*; D010502:Perineum / Q000293:injuries*; D011247:Pregnancy; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors