title: Ultrasound factors to predict the outcome of external cephalic version: a meta-analysis.
abstract: OBJECTIVE
  To systematically review the medical literature reporting on ultrasound factors that can be predictive for the outcome of an attempt at external cephalic version (ECV).
  
  
  METHODS
  MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials were searched. Studies reporting on potential ultrasound prognosticators and ECV success rates that allowed construction of a 2x2 table were selected.
  
  
  RESULTS
  We selected 37 primary articles reporting on 7709 women. Posterior placental location (odds ratio (OR), 1.9; 95% CI, 1.5-2.4), complete breech position (OR, 2.3; 95% CI, 1.9-2.8) and an amniotic fluid index>10 (OR, 1.8; 95% CI, 1.5-2.1) were predictors of successful ECV.
  
  
  CONCLUSIONS
  Success of an ECV attempt is associated with ultrasound parameters such as fetal position, amniotic fluid and placental location. This knowledge can be used to develop a prognostic model to predict successful ECV.
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. mkok@amc.uva.nl
authors.forename: M
authors.initials: M
authors.lastname: Kok
authors.forename: J
authors.initials: J
authors.lastname: Cnossen
authors.forename: L
authors.initials: L
authors.lastname: Gravendeel
authors.forename: J A
authors.initials: JA
authors.lastname: Van Der Post
authors.forename: B W
authors.initials: BW
authors.lastname: Mol
mesh_terms: D001946:Breech Presentation / Q000000981:diagnostic imaging / Q000628:therapy*; D002585:Cesarean Section / Q000706:statistics & numerical data; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D018570:Risk Assessment; D016216:Ultrasonography, Prenatal / Q000379:methods*; D014710:Version, Fetal / Q000379:methods* / Q000706:statistics & numerical data