title: Trends in major modifiable risk factors for severe perineal trauma, 1996-2006.
abstract: OBJECTIVE
  To examine what effect the major modifiable risk factors for severe perineal trauma have had on the rates of this trauma over time.
  
  
  METHODS
  A retrospective observational cohort study of singleton vaginal deliveries taken from a perinatal database for the period 1996 through 2006.
  
  
  RESULTS
  A total of 46,239 singleton vertex vaginal deliveries met the inclusion criteria. Major risk factors for severe perineal trauma were increased maternal age (odds ratio [OR] 1.28, 95% confidence interval [CI] 1.1-1.5), non-African American ethnicity (OR 1.5, 95% CI 1.3-1.7), nulliparity (OR 4.8, 95% CI 4.11-5.6), fetal birth weight (OR 2.2, 95% CI 1.9-2.4), forceps (OR 8.3, 95% CI 5.4-10.8), vacuum (OR 2.9, 95% CI 1.9-4.4), and midline episiotomy (OR 5.7, 95% CI 5.0-6.4). Evaluation of the changes in rates of these factors over the study period revealed that the decline in the rates of episiotomy and the use of forceps accounted for a reduction in severe lacerations of more than 50%.
  
  
  CONCLUSIONS
  Reduction of severe perineal trauma by restricted use of the 2 modifiable clinical variables, episiotomy and forceps, is evident over time.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Female Pelvic Medicine and Reconstructive Surgery, Washington Hospital Center, Washington DC 20010, USA. Bela.I.Kudish@medstar.net
authors.forename: Bela
authors.initials: B
authors.lastname: Kudish
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Sokol
authors.forename: Michael
authors.initials: M
authors.lastname: Kruger
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000293:injuries; D001724:Birth Weight; D036861:Delivery, Obstetric / Q000009:adverse effects*; D004841:Episiotomy / Q000706:statistics & numerical data; D005113:Extraction, Obstetrical / Q000009:adverse effects / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D022125:Lacerations / Q000453:epidemiology* / Q000517:prevention & control; D007744:Obstetric Labor Complications / Q000453:epidemiology* / Q000517:prevention & control; D016017:Odds Ratio; D010502:Perineum / Q000293:injuries*; D011247:Pregnancy; D012307:Risk Factors