Descent of the presenting part assessed with ultrasound

Fetal head descent can be expressed as fetal station and engagement. Station is traditionally based on clinical vaginal examination of the distal part skull related to level ischial spines. Engagement a transabdominal proximal above pelvic inlet. Clinical examinations are subjective, objective measurements warranted. Ultrasound feasible diagnostic tool in labor, lie, station, position, presentation, attitude examined. This review presents an overview examined with ultrasound.Ultrasound was first introduced for examining 1977. The distance from sacral tip measured A-mode ultrasound, but more convenient transperineal methods have since been published. Of those, progression distance, angle progression, head-symphysis sagittal plane, using inferior symphysis pubis reference point. Head-perineum frontal plane (transverse scan) shortest perineum skull, representing remaining birth canal fetus pass. At high stations, directed downward, followed horizontal then upward direction when descends deflexes head. Head may assessed transabdominally ultrasound suprapubic angle.Many observational studies shown that predict labor outcome before induction admission test, during second stage labor. Labor progress also longitudinally. International Society Obstetrics Gynecology recommends women prolonged or arrested malpositions malpresentations suspected, operative delivery. One single parameter cannot tell sure whether instrumental delivery going successful. Information about position prerequisite, direction, should considered. ultrasound. angle. Many Examining engagement part. Friedman Sachtleben1Friedman E.A. Sachtleben M.R. presenting I. Pattern descent.Am J Obstet Gynecol. 1965; 93: 522-529Abstract Full Text PDF PubMed Scopus (33) Google Scholar, 2Friedman IV. Slope 1970; 107: 1031-1034Abstract (6) 3Friedman 3. Interrelationship cervical dilatation.Am 537-542Abstract (14) 4Friedman II. Effect course labor.Am 530-536Abstract (20) 5Friedman V. Protracted patterns.Obstet 36: 558-567PubMed Scholar published pattern descent. Their important work digital estimation cavity. spines leading bony were used points, grading system −5 +5 cm. accelerated nulliparous cervix had reached 4 cm dilatation (Figure 1). curve implemented into partographs along his their use recommended worldwide.6World Health Organization partograph management labourWorld maternal health safe motherhood programme.Lancet. 1994; 343: 1399-1404PubMed Scholar,7World OrganizationWHO Labour Care Guide, user’s manual.Geneva. 2020; (ISBN 978-92-4-001757-3. Available at: https://cdn.who.int/media/docs/default-source/reproductive-health/maternal-health/who-labour-care-guide.pdf?sfvrsn=bd7fe865_15. Accessed September 10, 2020)Google A problem this there another divides cavity thirds −3 +3. Even though less commonly used, caregivers confused unless clearly stated.8Graseck A. Tuuli M. Roehl K. Odibo Macones G. Cahill labor.Obstet 2014; 123: 521-526Crossref (21) There has, recently, reassessment curves contemporary obstetrical populations. results Zhang et al9Zhang J. Troendle J.F. Yancey M.K. Reassessing women.Am 2002; 187: 824-828Abstract (259) showing both slower led applicability Friedman's being questioned. Similar later obtained study Graseck al,8Graseck who updated stratified by parity type. several problems connected station. First, spines, point, not always easy palpate, many find it difficult locate them. Second, 2 scoring systems use. Third, seem point head; 1 most states head, which gauged against other taught biparietal diameter Most aware these conflicting coexist within same unit. has recently described sides Atlantic.10Carollo T.C. Reuter J.M. Galan H.L. Jones R.O. Defining station.Am 2004; 191: 1793-1796Abstract (17) Scholar,11Awan N. Rhoades Weeks A.D. validity reliability StationMaster: device improve accuracy assessment labour.Eur Gynecol Reprod Biol. 2009; 145: 65-70Abstract (5) simulation found transvaginal poorly reliable.12Dupuis O. Silveira R. Zentner al.Birth simulator: defined American College Obstetricians Gynecologists classification.Am 2005; 192: 868-874Abstract (186) Another investigating interobserver agreement 508 term could estimated researchers 88% cases, 37% disagreement 47% cases.13Buchmann E. Libhaber Interobserver intrapartum station.Int Gynaecol Obstet. 2008; 101: 285-289Crossref (58) Researchers studying decades acknowledged subjective nature method called than palpation.1Friedman Scholar,9Zhang Scholar,14Hamilton E.F. Simoneau Ciampi al.Descent (station) 2016; 214: 360.e1-360.e6Abstract (10) During last 20 years, describing various standardized purpose.15Barbera A.F. Pombar X. Perugino Lezotte D.C. Hobbins J.C. new assess 33: 313-319Crossref (205) 16Dietz H.P. Lanzarone Measuring head: reproducibility technique.Ultrasound 25: 165-168Crossref (137) 17Eggebø T.M. Gjessing L.K. Heien C. al.Prediction pregnancies prelabor rupture membranes at term.Ultrasound 2006; 27: 387-391Crossref (126) 18Henrich W. Dudenhausen Fuchs Kämena Tutschek B. Intrapartum translabial (ITU): sonographic landmarks correlation successful vacuum extraction.Ultrasound 28: 753-760Crossref (150) 19Youssef Maroni Ragusa al.Fetal distance: simple reliable index labor.Ultrasound 2013; 41: 419-424Crossref (77) An now possible, editorials implement care.20Yeo L. Romero Sonographic evaluation its outcome.Ultrasound 253-258Crossref (56) 21Ugwumadu role scanning ward.Ultrasound 19: 222-224Crossref 22Sherer D.M. 2007; 30: 123-139Crossref (37) 23Ville Y. From obstetric ultrasonographic obstetrics.Ultrasound 1-5Crossref (15) 24Eggebø future active 361-363Crossref Lewin al25Lewin D. Sadoul Beuret T. height cephalic presentation: station.Eur 1977; 7: 369-372Abstract (18) Paris examine they transducer placed tip, sacrum Richey sonography 1995 plane.26Richey S.D. Ramin K.D. Roberts S.W. S.M. Cox Twickler between third-trimester cervix.Obstet 1995; 85: 745-748Crossref (24) In 1996, Voskresynsky27Voskresynsky SL. Biomechanics labour, Minsk; ISBN 985-6178-11-8; 1996.Google biomechanics presented thesis unfortunately gained little attention because Russian. Transperineal demonstrated Video. Dietz Lanzarone16Dietz They instead al,26Richey terms approach, recommended.28Salvesen K.A. imaging floor: ‘what name shall given Child?’.Ultrasound 750-752Crossref (2) line vertical central axis margin (infrapubic line) lowermost 2).16Dietz strong assessments found,16Dietz antenatal prediction deliveries.29Dietz Simpson Predicting delivery.Ultrasound 409-415Crossref (60) clinically useful 2006 Henrich al.18Henrich approach relation extraction; 17 fetuses occiput anterior 3 posterior position. up sign good prognostic factor delivery.18Henrich research group three-dimensional computer tomography reconstruction corresponding below infrapubic line.30Armbrust Hinkson al.Correlation parameters computed tomographic 3D female pelvis.J Perinat Med. 44: 567-571Crossref (3) measuring 3).31Tutschek Braun Chantraine F. labour assessing descent.BJOG. 2011; 118: 62-69Crossref (113) affect where changes, different positions.32Ghi Youssef al.Sonographic descent: relationship duration 82-89Crossref (41) (AoP), Barbera al15Barbera 2009. transperineally through long end tangentially contour 4). original publication, dynamic process, all examined; thus, changed AoP. geometric model images nonpregnant 99° correlate correlated station.33Barbera Imani Becker Anatomic pubic significance 320-325Crossref (57) Arthuis al34Arthuis C.J. Perrotin Patat Brunereau Simon E.G. Computed anatomical interpretation 48: 779-785Crossref studied AoP 110°. Bamberg al35Bamberg Scheuermann S. Slowinski al.Relationship established open magnetic resonance scanner determined 37: 712-716Crossref (31) pregnant women. 120° spines.35Bamberg Scholar,36Bamberg Fotopoulou al.Angle term: systematic comparison ultrasound.Am 2012; 206: 161.e1-161.e5Abstract (19) compared showed mean difference only 1.4°. al37Tutschek Torkildsen Eggebø Comparison 425-429Crossref (72) zero 116°. reproducible descent.38Molina F.S. Terra Carrillo M.P. Puertas Nicolaides K.H. What descent?.Ultrasound 2010; 493-499Crossref (85) labor.39Ghi al.Intrapartum mode 430-435Crossref (54) 40Hadad Oberman Ben-Arie Sacagiu Vaisbuch Levy initiation predicts spontaneous delivery.Am MFM. 2021; 3: 100249Abstract 41Hjartardottir H. Lund S.H. Benediktsdottir Geirsson R.T. Can delivery?.Am ([Epub ahead print])Abstract (4) 42Gillor Zaks Barak Hagay Z. predictor following 2017; 49: 240-245Crossref (22) 43Pereira Frick A.P. Poon L.C. Zamprakou Successful labor: preinduction length, elastography.Ultrasound 468-475Crossref (61) 44Frick Kostiv Vojtassakova Akolekar 55: 391-400Crossref 45Kahrs B.H. Usman Ghi deliveries: multicenter, prospective cohort study.Am 217: 69.e1-69.e10Abstract (48) 46Eggebø Hassan W.A. Salvesen K.Å. Lindtjørn Lees C.C. two-center study.Ultrasound 43: 195-201Crossref (47) 47Torkildsen Prediction 702-708Crossref (91) 48Kamel R.A. Negm al.Predicting cesarean failure singleton pregnancy.Am 224: 609.e1-609.e11Abstract (7) delivery.49Ghi al.ISUOG Practice Guidelines: 2018; 52: 128-139Crossref (93) However, optimal cutoff discussed, angles varying 145.5° studies.15Barbera Scholar,50Kalache Dückelmann A.M. Michaelis S.A. Lange Cichon J.W. occipitoanterior fetuses: how well does ’angle progression’ delivery?.Ultrasound 326-330Crossref (158) 51Cuerva M.J. Tobias P. Gil M.M. De La Calle Bartha J.L. Use complicated forceps non-occiput position.Ultrasound 687-692Crossref (38) 52Sainz J.A. Borrero Fernández-Palacín instrumentation difficulty vacuum-assisted primiparous women.J Matern Neonatal 2015; 2041-2047Crossref (13) 53Bultez Quibel Bouhanna Popowski Resche-Rigon Rozenberg Angle predictive extraction failure.Ultrasound 86-91Crossref study, >120°, associated subsequent delivery.15Barbera Kalache al50Kalache 26 confirmed occurred 90% >120°. Bultez al53Bultez 235 procedure >20 minutes detachment cup >3 times. rate 5% if >145.5° Fetuses positions included. It major limitation inclusions outcomes vary publications, no randomized design. value differ among positions, deeper third cardinal movement (flexion) starts (extension) positions.54Iversen J.K. Kahrs 4, 7, movements (1) maximally flexed, follow optimally position.32Ghi o