{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,27]],"date-time":"2026-10-27T12:44:33Z","timestamp":1793105073024,"version":"4.5.0"},"reference-count":39,"publisher":"Elsevier BV","issue":"1","license":[{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/legal\/tdmrep-license"},{"start":{"date-parts":[[2023,10,15]],"date-time":"2023-10-15T00:00:00Z","timestamp":1697328000000},"content-version":"am","delay-in-days":287,"URL":"http:\/\/www.elsevier.com\/open-access\/userlicense\/1.0\/"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-017"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-012"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2023,1,1]],"date-time":"2023-01-01T00:00:00Z","timestamp":1672531200000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-004"}],"content-domain":{"domain":["ajogmfm.org","elsevier.com","sciencedirect.com"],"crossmark-restriction":true},"short-container-title":["American Journal of Obstetrics & Gynecology MFM"],"published-print":{"date-parts":[[2023,1]]},"DOI":"10.1016\/j.ajogmf.2022.100755","type":"journal-article","created":{"date-parts":[[2022,9,23]],"date-time":"2022-09-23T05:01:06Z","timestamp":1663909266000},"page":"100755","update-policy":"https:\/\/doi.org\/10.1016\/elsevier_cm_policy","source":"Crossref","is-referenced-by-count":3,"title":["The head direction to the angle of progression ratio: a quantitative parameter for intrapartum evaluation of cephalic malposition"],"prefix":"10.1016","volume":"5","author":[{"given":"Eriko","family":"Yano","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7970-6695","authenticated-orcid":false,"given":"Takayuki","family":"Iriyama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seisuke","family":"Sayama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Ariyosi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoya","family":"Akiba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mari","family":"Ichinose","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masatake","family":"Toshimitsu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahiro","family":"Seyama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenbun","family":"Sone","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keiichi","family":"Kumasawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takeshi","family":"Nagamatsu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toshio","family":"Nakayama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koichi","family":"Kobayashi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutaka","family":"Osuga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","reference":[{"key":"10.1016\/j.ajogmf.2022.100755_bib0001","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1002\/uog.19072","article-title":"ISUOG Practice Guidelines: intrapartum ultrasound","volume":"52","author":"Ghi","year":"2018","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0002","doi-asserted-by":"crossref","first-page":"493","DOI":"10.1002\/uog.7709","article-title":"What is the most reliable ultrasound parameter for assessment of fetal head descent?","volume":"36","author":"Molina","year":"2010","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0003","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1111\/1471-0528.12810","article-title":"Instrumental delivery and ultrasound: a multicentre randomised controlled trial of ultrasound assessment of the fetal head position versus standard care as an approach to prevent morbidity at instrumental delivery","volume":"121","author":"Ramphul","year":"2014","journal-title":"BJOG"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0004","doi-asserted-by":"crossref","first-page":"326","DOI":"10.1002\/uog.6294","article-title":"Transperineal ultrasound imaging in prolonged second stage of labor with occipitoanterior presenting fetuses: how well does the \u2018angle of progression\u2019 predict the mode of delivery?","volume":"33","author":"Kalache","year":"2009","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0005","doi-asserted-by":"crossref","first-page":"2408","DOI":"10.3109\/14767058.2015.1092137","article-title":"Intrapartum sonographic signs: new diagnostic tools in malposition and malrotation","volume":"29","author":"Malvasi","year":"2016","journal-title":"J Matern Fetal Neonatal Med"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0006","doi-asserted-by":"crossref","first-page":"192","DOI":"10.1002\/ijgo.12712","article-title":"Measuring angle of progression by transperineal ultrasonography to predict successful instrumental and cesarean deliveries during prolonged second stage of labor","volume":"144","author":"Chan","year":"2019","journal-title":"Int J Gynaecol Obstet"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0007","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1002\/uog.14951","article-title":"Angle of fetal head progression measured using transperineal ultrasound as a predictive factor of vacuum extraction failure","volume":"48","author":"Bultez","year":"2016","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0008","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1002\/uog.3848","article-title":"Intrapartum translabial ultrasound (ITU): sonographic landmarks and correlation with successful vacuum extraction","volume":"28","author":"Henrich","year":"2006","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0009","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.ajogmf.2019.05.001","article-title":"A simple sonographic finding is associated with a successful vacuum application: the fetal occiput or forehead sign","volume":"1","author":"Bellussi","year":"2019","journal-title":"Am J Obstet Gynecol MFM"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0010","doi-asserted-by":"crossref","first-page":"735","DOI":"10.1002\/uog.6400","article-title":"What is the best transperineal ultrasound parameter for predicting success of vacuum extraction?","volume":"33","author":"Lau","year":"2009","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0011","first-page":"746","article-title":"Intrapartum sonography and persistent occiput posterior position: a study of 408 deliveries","volume":"91","author":"Gardberg","year":"1998","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0012","doi-asserted-by":"crossref","first-page":"974","DOI":"10.1097\/01.AOG.0000158861.43593.49","article-title":"Changes in fetal position during labor and their association with epidural analgesia","volume":"105","author":"Lieberman","year":"2005","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0013","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1002\/uog.1064","article-title":"Investigation of occiput posterior delivery by intrapartum sonography","volume":"24","author":"Akmal","year":"2004","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0014","doi-asserted-by":"crossref","DOI":"10.1016\/j.ajog.2020.10.054","article-title":"When does fetal head rotation occur in spontaneous labor at term: results of an ultrasound-based longitudinal study in nulliparous women","volume":"224","author":"Hjartard\u00f3ttir","year":"2021","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0015","first-page":"1027","article-title":"Influence of persistent occiput posterior position on delivery outcome","volume":"98","author":"Fitzpatrick","year":"2001","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0016","first-page":"915","article-title":"Persistent fetal occiput posterior position: obstetric outcomes","volume":"101","author":"Ponkey","year":"2003","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0017","doi-asserted-by":"crossref","first-page":"1702","DOI":"10.1016\/j.ajog.2004.11.047","article-title":"The impact of occiput posterior fetal head position on the risk of anal sphincter injury in forceps-assisted vaginal deliveries","volume":"192","author":"Benavides","year":"2005","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0018","doi-asserted-by":"crossref","first-page":"837","DOI":"10.1097\/01.AOG.0000206217.07883.a2","article-title":"The association between persistent occiput posterior position and neonatal outcomes","volume":"107","author":"Cheng","year":"2006","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0019","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1016\/j.ajog.2005.03.059","article-title":"Occiput posterior fetal head position increases the risk of anal sphincter injury in vacuum-assisted deliveries","volume":"193","author":"Wu","year":"2005","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0020","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1097\/AOG.0000000000001273","article-title":"Predictors of failed operative vaginal delivery in a contemporary obstetric cohort","volume":"127","author":"Palatnik","year":"2016","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0021","doi-asserted-by":"crossref","first-page":"610","DOI":"10.1046\/j.1471-0528.2003.01463.x","article-title":"Cohort study of operative delivery in the second stage of labour and standard of obstetric care","volume":"110","author":"Murphy","year":"2003","journal-title":"BJOG"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0022","doi-asserted-by":"crossref","first-page":"1203","DOI":"10.1016\/S0140-6736(01)06341-3","article-title":"Early maternal and neonatal morbidity associated with operative delivery in second stage of labour: a cohort study","volume":"358","author":"Murphy","year":"2001","journal-title":"Lancet"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0023","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1002\/uog.13324","article-title":"Sonographic pattern of fetal head descent: relationship with duration of active second stage of labor and occiput position at delivery","volume":"44","author":"Ghi","year":"2014","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0024","article-title":"Sonographic diagnosis of fetal head deflexion and the risk of cesarean delivery","volume":"2","author":"Bellussi","year":"2020","journal-title":"Am J Obstet Gynecol MFM"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0025","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1002\/uog.21913","article-title":"Comparison of different methods of measuring angle of progression in prediction of labor outcome","volume":"55","author":"Frick","year":"2020","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0026","doi-asserted-by":"crossref","first-page":"3175","DOI":"10.1080\/14767058.2019.1678143","article-title":"Reliability of transperineal ultrasound for the assessment of the angle of progression in labor using parasagittal approach versus midsagittal approach","volume":"34","author":"Kamel","year":"2021","journal-title":"J Matern Fetal Neonatal Med"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0027","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1002\/uog.12335","article-title":"Fetal head-symphysis distance: a simple and reliable ultrasound index of fetal head station in labor","volume":"41","author":"Youssef","year":"2013","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0028","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1002\/uog.1765","article-title":"Measuring engagement of the fetal head: validity and reproducibility of a new ultrasound technique","volume":"25","author":"Dietz","year":"2005","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0029","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1111\/j.1471-0528.2010.02775.x","article-title":"A study of progress of labour using intrapartum translabial ultrasound, assessing head station, direction, and angle of descent","volume":"118","author":"Tutschek","year":"2011","journal-title":"BJOG"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0030","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1002\/uog.6313","article-title":"Diagnosis of station and rotation of the fetal head in the second stage of labor with intrapartum translabial ultrasound","volume":"33","author":"Ghi","year":"2009","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0031","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1016\/j.ajog.2017.07.025","article-title":"The use of intrapartum ultrasound to diagnose malpositions and cephalic malpresentations","volume":"217","author":"Bellussi","year":"2017","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0032","doi-asserted-by":"crossref","first-page":"535","DOI":"10.1002\/uog.19169","article-title":"How reliable is fetal occiput and spine position assessment prior to induction of labor?","volume":"53","author":"Kamel","year":"2019","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0033","volume":"1","author":"Cunningham","year":"2018"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0034","doi-asserted-by":"crossref","first-page":"249","DOI":"10.15557\/JoU.2019.0037","article-title":"Comparing intrapartum ultrasound and clinical examination in the assessment of fetal head position in African women","volume":"19","author":"Wiafe","year":"2019","journal-title":"J Ultrason"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0035","doi-asserted-by":"crossref","first-page":"210","DOI":"10.1002\/uog.7504","article-title":"Sonographic assessment of fetal spine and head position during the first and second stages of labor for the diagnosis of persistent occiput posterior position: a pilot study","volume":"35","author":"Blasi","year":"2010","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0036","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1080\/jmf.13.1.59.63","article-title":"Intrapartum ultrasound for the examination of the fetal head position in normal and obstructed labor","volume":"13","author":"Souka","year":"2003","journal-title":"J Matern Fetal Neonatal Med"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0037","doi-asserted-by":"crossref","first-page":"65","DOI":"10.14390\/jsshp.2.65","article-title":"Fetal station based on the trapezoidal plane and assessment of head descent during instrumental delivery","volume":"2","author":"Takeda","year":"2014","journal-title":"Hypertens Res Pregnancy"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0038","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1002\/uog.6329","article-title":"A new method to assess fetal head descent in labor with transperineal ultrasound","volume":"33","author":"Barbera","year":"2009","journal-title":"Ultrasound Obstet Gynecol"},{"key":"10.1016\/j.ajogmf.2022.100755_bib0039","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1002\/uog.7752","article-title":"Three-dimensional ultrasound in monitoring progression of labor: a reproducibility study","volume":"36","author":"Ghi","year":"2010","journal-title":"Ultrasound Obstet Gynecol"}],"container-title":["American Journal of Obstetrics & Gynecology MFM"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S2589933322001860?httpAccept=text\/xml","content-type":"text\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S2589933322001860?httpAccept=text\/plain","content-type":"text\/plain","content-version":"vor","intended-application":"text-mining"}],"deposited":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T23:51:47Z","timestamp":1762905107000},"score":1,"resource":{"primary":{"URL":"https:\/\/linkinghub.elsevier.com\/retrieve\/pii\/S2589933322001860"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,1]]},"references-count":39,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2023,1]]}},"alternative-id":["S2589933322001860"],"URL":"https:\/\/doi.org\/10.1016\/j.ajogmf.2022.100755","relation":{},"ISSN":["2589-9333"],"issn-type":[{"value":"2589-9333","type":"print"}],"subject":[],"published":{"date-parts":[[2023,1]]},"assertion":[{"value":"Elsevier","name":"publisher","label":"This article is maintained by"},{"value":"The head direction to the angle of progression ratio: a quantitative parameter for intrapartum evaluation of cephalic malposition","name":"articletitle","label":"Article Title"},{"value":"American Journal of Obstetrics & Gynecology MFM","name":"journaltitle","label":"Journal Title"},{"value":"https:\/\/doi.org\/10.1016\/j.ajogmf.2022.100755","name":"articlelink","label":"CrossRef DOI link to publisher maintained version"},{"value":"article","name":"content_type","label":"Content Type"},{"value":"\u00a9 2022 Elsevier Inc. All rights reserved.","name":"copyright","label":"Copyright"}],"article-number":"100755"}}