{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T14:58:06Z","timestamp":1774277886615,"version":"3.50.1"},"reference-count":88,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T00:00:00Z","timestamp":1774224000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Operative vaginal delivery (OVD) via vacuum extraction is a fundamental component of modern obstetric management, yet it carries specific risks of failure and maternal\u2013fetal complications, such as cup detachment, cephalohematoma, and intracranial hemorrhage. The success and safety of the procedure rely heavily on the correct application of the vacuum cup over the \u201cflexion point\u201d of the fetal head. Traditional identification of this landmark via digital examination is often hindered by caput succedaneum and cranial molding, leading to high rates of diagnostic error, particularly in dystocic labor, due to fetal head malpositions and malpresentation. Intrapartum ultrasound (ITU) has demonstrated superior accuracy compared to clinical examination in assessing fetal head position and station and internal rotation. This expert commentary and technical proposal analyzes the current literature regarding vacuum extraction application and failures, focusing on the predictive value of ITU parameters (e.g., Angle of Progression, Midline Angle, Head-Symphysis Distance) and the impact of ITU on cup placement and delivery outcomes. Furthermore, we propose a novel technique: the \u201cUltrasound Flexion Point\u201d (UFP). This method utilizes translabial ultrasound to identify the specific intersection of the fetal midline and the biparietal diameter as an objective sonographic proxy for the classical flexion point. By providing spatial orientation guidance immediately before the procedure, this technique aims to guide the operator in aligning the cup\u2019s notch with the sonographically identified target zone, using the midline angle as orientation reference, thereby potentially minimizing paramedian or deflexing applications and reducing the incidence of vacuum detachment and associated neonatal trauma. This expert commentary and technical proposal synthesizes current evidence and proposes a protocol requiring prospective validation through randomized controlled trials.<\/jats:p>","DOI":"10.3390\/diagnostics16060946","type":"journal-article","created":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T13:53:34Z","timestamp":1774274014000},"page":"946","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Intrapartum Ultrasound in Vacuum Operative Delivery: A Comprehensive Review and Proposal of the Novel Ultrasound Flexion Point Method"],"prefix":"10.3390","volume":"16","author":[{"given":"Antonio","family":"Malvasi","sequence":"first","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5061-8007","authenticated-orcid":false,"given":"Giorgio Maria","family":"Baldini","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9711-3497","authenticated-orcid":false,"given":"Tommaso","family":"Difonzo","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2918-3608","authenticated-orcid":false,"given":"Marco","family":"Cerbone","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Iris","family":"Cara","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marianna","family":"Demarco","sequence":"additional","affiliation":[{"name":"Medical School, University of Bari, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilenia","family":"Mappa","sequence":"additional","affiliation":[{"name":"Department of Maternal and Child Health and Urological Sciences, University of Roma Sapienza, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5525-4353","authenticated-orcid":false,"given":"Giuseppe","family":"Rizzo","sequence":"additional","affiliation":[{"name":"Department of Maternal and Child Health and Urological Sciences, University of Roma Sapienza, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9862-1619","authenticated-orcid":false,"given":"Antonella","family":"Vimercati","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3522-4648","authenticated-orcid":false,"given":"Miriam","family":"Dellino","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8426-8490","authenticated-orcid":false,"given":"Andrea","family":"Tinelli","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology and CERICSAL (CEntro di RIcerca Clinico SALentino), Veris Delli Ponti Hospital Scorrano, 73020 Lecce, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Edoardo","family":"Di Naro","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Unit, Department of Interdisciplinary Medicine (DIM), University of Bari \u201cAldo Moro\u201d, 70124 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0606-6425","authenticated-orcid":false,"given":"Lorenzo E.","family":"Malgieri","sequence":"additional","affiliation":[{"name":"The New European Surgical Academy (NESA), 10117 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"American College of Obstetricians and Gynecologists (2020). 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