title: A multicenter interventional program to reduce the incidence of anal sphincter tears.
abstract: OBJECTIVE
  In Norway, we have experienced a gradual increase in the incidence of obstetric anal sphincter injuries from under 1% in the late 1960s to 4.3% in 2004. This study was aimed to assess whether an interventional program causes a decrease in the frequency of anal sphincter tears.
  
  
  METHODS
  In all, 40,152 vaginal deliveries between 2003 and 2009 were enrolled in the interventional cohort study from four Norwegian obstetric departments. The focus of the intervention was on manual assistance during the final part of the second stage of labor. Data were analyzed in relation to occurrence of obstetric anal sphincter tears.
  
  
  RESULTS
  The proportion of parturients with anal sphincter tears decreased from 4-5% to 1-2% during the study period in all four hospitals (P<.001). The tears associated with both noninstrumental and instrumental deliveries decreased dramatically. The number of patients with grades 3 and 4 anal sphincter ruptures decreased significantly, and the reduction was most pronounced in grade 4 tears (-63.5%) and least in 3c tears (-47.5%) (both P<.001). The number of episiotomies increased in two hospitals but remained unchanged in the other two. The lowest proportion of tears at the end of the intervention (1.2% and 1.3%, respectively) was found in the two hospitals with an unchanged episiotomy rate.
  
  
  CONCLUSIONS
  The multicenter intervention caused a highly significant decrease in obstetric anal sphincter injuries.
  
  
  METHODS
  II.
authors.affiliation: From the Department of Obstetrics and Gynecology, Innlandet Hospital Trust, Lillehammer, Norway; the Department of Obstetrics and Gynecology and Institute of Clinical Medicine, University Hospital of Northern Norway/University of Tromsø, Tromsø, Norway; The Norwegian Continence and Pelvic Floor Center, University Hospital of North Norway, Tromsø, Norway; the National Institute for Health and Welfare, Helsinki, Finland; the Nordic School of Public Health, Gothenburg, Sweden; and the Departments of Obstetrics and Gynecology, Ålesund Hospital, Ålesund, Norway; Stavanger University Hospital, Stavanger, Norway; and Oslo University Hospital, University of Oslo, Oslo Norway.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hals
authors.forename: Pål
authors.initials: P
authors.lastname: Øian
authors.forename: Tiina
authors.initials: T
authors.lastname: Pirhonen
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
authors.forename: Sissel
authors.initials: S
authors.lastname: Hjelle
authors.forename: Elisabeth Berge
authors.initials: EB
authors.lastname: Nilsen
authors.forename: Anne Mette
authors.initials: AM
authors.lastname: Severinsen
authors.forename: Cathrine
authors.initials: C
authors.lastname: Solsletten
authors.forename: Tom
authors.initials: T
authors.lastname: Hartgill
authors.forename: Jouko
authors.initials: J
authors.lastname: Pirhonen
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000293:injuries*; D004841:Episiotomy; D005260:Female; D006801:Humans; D007748:Labor Stage, Second; D007744:Obstetric Labor Complications / Q000517:prevention & control*; D011247:Pregnancy; D012421:Rupture