{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,1]],"date-time":"2026-11-01T01:24:45Z","timestamp":1793496285202,"version":"4.5.0"},"reference-count":49,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T00:00:00Z","timestamp":1767657600000},"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>Complex or difficult cesareans are associated with significant short- and long-term complications. The complication rate increases with the increasing number of cesareans, and the incidence of cesarean section is increasing. To accurately identify women at high risk of surgical difficulty during a cesarean, ultrasound, in addition to clinical assessment, can be used to evaluate many risk factors, including placenta previa, placenta accreta spectrum (PAS) disorders, fibroids, severe pelvic adhesions, and membranous fetal vessels. The role of preoperative ultrasound is to identify ultrasonographic signs of anatomic changes that may affect the risk of intraoperative complications in subsequent cesarean sections. It is important to look for maternal problems as well as fetal problems. Ultrasound is a well-established practice in obstetrical care as it is easily available, accessible, easy to perform, and well accepted by women. However, there are few studies on the role of preoperative ultrasound in the management of complex or difficult cesareans beyond the risk assessment of PAS. Currently, preoperative ultrasound is mostly performed in selected cases only, with the exception in some settings. The aim of this review article is to discuss the benefits and the use of ultrasound assessment before different types of complex or difficult cesareans. Whether ultrasound assessment should be performed before all cesarean sections will also be discussed.<\/jats:p>","DOI":"10.3390\/diagnostics16020178","type":"journal-article","created":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T11:13:18Z","timestamp":1767697998000},"page":"178","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Ultrasound Assessment Before Complex or Difficult Cesarean Section"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9289-6857","authenticated-orcid":false,"given":"Kwok-yin","family":"Leung","sequence":"first","affiliation":[{"name":"Obstetrics and Gynaecology, Gleneagles Hospital Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1002\/ijgo.16094","article-title":"Complex cesarean section: Surgical approach to reduce the risks of intraoperative complications and postpartum hemorrhage","volume":"168","author":"Ramasauskaite","year":"2025","journal-title":"Int. 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