title: Use of intrapartum ultrasound in the prediction of complicated operative forceps delivery of fetuses in non-occiput posterior position.
abstract: OBJECTIVE
  To evaluate the hypothesis that intrapartum ultrasound (ITU) measurements, including the angle of progression (AOP), progression distance (PD) and head direction (HD), can predict complicated forceps delivery in non-occiput posterior deliveries.
  
  
  METHODS
  In this prospective observational study, a single operator performed ITU on 30 patients with an indication for operative forceps delivery. Managing obstetricians were blinded to the results. ITU was performed just before blade application, between contractions and concurrently with contractions and active pushing. Forceps delivery was classified as complicated when one or more of the following situations occurred: three or more tractions; a subjective impression of a difficult or failed application; a third-degree or higher perineal tear; significant bleeding during the episiotomy repair; major tear; significant traumatic neonatal lesion.
  
  
  RESULTS
  Twenty-one forceps deliveries were classified as uncomplicated and nine were complicated. The strongest predictor of a complicated forceps delivery, calculated using the area under the receiver-operating characteristics curve (AUC), was the AOP between contractions (AOP1) (AUC = 98.9%). The best cut-off for predicting a difficult forceps delivery was an AOP1 of 138° (sensitivity = 85.7%, specificity = 100%). The best predictive model included both the AOP1 and the HD during a contraction with active pushing (HD2).
  
  
  CONCLUSIONS
  The sonographic parameters AOP and HD can be used to predict complicated operative forceps delivery in fetuses in non-occiput posterior position.
authors.affiliation: Department of Obstetrics, La Paz University Hospital, Madrid, Spain.
authors.forename: M J
authors.initials: MJ
authors.lastname: Cuerva
authors.forename: C
authors.initials: C
authors.lastname: Bamberg
authors.forename: P
authors.initials: P
authors.lastname: Tobias
authors.forename: M M
authors.initials: MM
authors.lastname: Gil
authors.forename: M
authors.initials: M
authors.lastname: De La Calle
authors.forename: J L
authors.initials: JL
authors.lastname: Bartha
mesh_terms: D000328:Adult; D019540:Area Under Curve; D001724:Birth Weight; D004841:Episiotomy / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007746:Labor Presentation; D007744:Obstetric Labor Complications / Q000000981:diagnostic imaging / Q000517:prevention & control*; D009772:Obstetrical Forceps / Q000706:statistics & numerical data; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D014463:Ultrasonography
keywords: angle of progression; forceps; head direction; intrapartum ultrasound; labor; progression distance