title: Risk factors for sonographic internal anal sphincter gaps 6-12 months after delivery complicated by anal sphincter tear.
abstract: OBJECTIVE
  The objective of the study was to identify risk factors for internal anal sphincter (IAS) gaps on postpartum endoanal ultrasound in women with obstetric anal sphincter tear.
  
  
  METHODS
  This prospective study included 106 women from the Childbirth and Pelvic Symptoms Imaging Supplementary Study who had third- or fourth-degree perineal laceration at delivery and endoanal ultrasound 6-12 months postpartum. Data were analyzed using Fisher's exact and t tests and logistic regression.
  
  
  RESULTS
  Mean (+/- SD) age was 27.7 (+/- 6.2) years. Seventy-nine women (76%) were white and 22 (21%) black. Thirty-seven (35%) had sonographic IAS gaps. Risk factors for gaps included fourth- vs third-degree perineal laceration (odds ratio [OR] 15.4, 95% confidence interval [CI] 4.8, 50) and episiotomy (OR 3.3, 95% CI 1.2, 9.1). Black race (OR 0.23, 95% CI 0.05, 0.96) was protective.
  
  
  CONCLUSIONS
  In women with obstetric anal sphincter repairs, fourth-degree tears and episiotomy are associated with more frequent sonographic IAS gaps.
authors.affiliation: Department of Obstetrics and Gynecology, University of Iowa, Iowa City, IA, USA.
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Bradley
authors.forename: Holly E
authors.initials: HE
authors.lastname: Richter
authors.forename: Robert E
authors.initials: RE
authors.lastname: Gutman
authors.forename: Morton B
authors.initials: MB
authors.lastname: Brown
authors.forename: William E
authors.initials: WE
authors.lastname: Whitehead
authors.forename: Paul M
authors.initials: PM
authors.lastname: Fine
authors.forename: Christiane
authors.initials: C
authors.lastname: Hakim
authors.forename: Frank
authors.initials: F
authors.lastname: Harford
authors.forename: Anne M
authors.initials: AM
authors.lastname: Weber
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D001004:Anus Diseases / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D036861:Delivery, Obstetric / Q000009:adverse effects*; D004841:Episiotomy; D005260:Female; D006801:Humans; D022125:Lacerations / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D007744:Obstetric Labor Complications / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D014463:Ultrasonography