title: Intrapartum translabial ultrasound with pushing used to predict the difficulty in vacuum-assisted delivery of fetuses in non-occiput posterior position.
abstract: OBJECTIVE
  Our aim is to evaluate the capacity of intrapartum translabial ultrasound (ITU) with pushing in the prediction of difficulty of fetal extraction in vacuum assisted deliveries. Prospective, observational study performed (2/2015-8/2015) on 75 nulliparous women, ≥37 weeks with singleton pregnancies at full dilatation who had ITU-with-pushing performed, previous to vacuum-placement for fetal extraction. Working on the translabial sagittal-plane, we assessed: Angle-Progression (AoP), Progression-Distance (PD) and Head-Direction (HD); in the axial plane we evaluated: Midline-Angle (MLA) and Head-Perineum-Distance (HPD). Vacuum extractions were classified as easy-difficulty (ED) (≤3 vacuum-pulls), difficult-unsuccessful (DD) (>3 vacuum-pulls). We did not assess occipito-posterior-presentations.
  
  
  RESULTS
  Seventy nulliparous were studied (44-ED,26-DD). We observed no differences in obstetric, neonatal or intrapartum characteristics between the two study groups, with the following exceptions: newborn weight (3272 ± 438 g versus 3540 ± 372 g; p = 0.011) and number of vacuum-pulls (1.4-ED-vs-4.4-DD; p < 0.0005). AoP-pushing was 143.9° ± 14.6° in ED and 115.1°± 12.9° in DD (p < 0.0005); Head-Up was 79.5% versus 38.4% (p < 0.0005); PD-Pushing was 42.7 ± 11.3 mm versus 30.4 ± 9.8 mm (p < 0.0005); MLA-Pushing was 27.6°± 26.6° versus 57.5°±26.5°(p=0.025); HPD-Pushing was 40.8 ± 10.0 mm versus 47.4 ± 10.9 mm (p = 0.039).
  
  
  CONCLUSIONS
  We identified that the presence of an AoP-Pushing > 128° predicts an Easy-Vacuum-Delivery (≤3 Vacuum-Pulls) in  >85% of cases (Sen 80%-FPR 9.3%).
authors.affiliation: a Department of Obstetrics and Gynecology , Valme University Hospital , Seville , Spain .|b Department of Obstetrics and Gynecology , University of Seville , Spain , and.
authors.forename: José
authors.initials: J
authors.lastname: Antonio Sainz
authors.affiliation: a Department of Obstetrics and Gynecology , Valme University Hospital , Seville , Spain .
authors.forename: Carlota
authors.initials: C
authors.lastname: Borrero
authors.affiliation: a Department of Obstetrics and Gynecology , Valme University Hospital , Seville , Spain .
authors.forename: Adriana
authors.initials: A
authors.lastname: Aquise
authors.affiliation: a Department of Obstetrics and Gynecology , Valme University Hospital , Seville , Spain .
authors.forename: José Antonio
authors.initials: JA
authors.lastname: García-Mejido
authors.affiliation: a Department of Obstetrics and Gynecology , Valme University Hospital , Seville , Spain .
authors.forename: Laura
authors.initials: L
authors.lastname: Gutierrez
authors.affiliation: c Biostatistics Unit, Department of Preventive Medicine and Public Health , University of Seville , Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Fernández-Palacín
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007746:Labor Presentation; D007748:Labor Stage, Second; D007744:Obstetric Labor Complications / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal; D014620:Vacuum Extraction, Obstetrical; D055815:Young Adult
keywords: Intrapartum ultrasound; labor; pushing; transperineal ultrasound; vacuum delivery