{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T02:03:37Z","timestamp":1767837817117,"version":"3.49.0"},"reference-count":23,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2022,9,1]],"date-time":"2022-09-01T00:00:00Z","timestamp":1661990400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Ultrasound in Obstet &amp;amp; Gyne"],"published-print":{"date-parts":[[2022,9]]},"abstract":"<jats:title>ABSTRACT<\/jats:title><jats:sec><jats:title>Objective<\/jats:title><jats:p>To assess the performance of the \u2018separation sign\u2019 as a predictor of normal placental separation in a large cohort of women at risk for placenta accreta spectrum (PAS) and in a high\u2010risk subgroup with placenta previa or anterior low\u2010lying placenta and at least one previous Cesarean delivery.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>This was a prospective study of women at risk for PAS referred to a specialist clinic at between 22 and 38\u2009weeks' gestation. All women underwent ultrasound assessment for the presence of the separation sign, which detects the difference in elasticity between the myometrium and the placenta, characterized by different rates of rebound after an ultrasound probe is used to apply pressure over the uteroplacental interface. When the sign is positive, the placenta appears to move relative to the myometrium, leading to the appearance or enhancement of the clear zone. The predictive performance of the separation sign for normal spontaneous placental separation at delivery was assessed.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Of the 194 included women, 163 had a positive separation sign, all of whom went on to have normal placental separation at delivery. Of the 24 women with a negative separation sign, three (12.5%) had normal placental separation and 21 (87.5%) were diagnosed with PAS. This yielded a sensitivity of 98.2% (95%\u2009CI, 94.8\u201399.6%) and specificity of 100% (95%\u2009CI, 83.9\u2013100%). In the high\u2010risk cohort (<jats:italic>n<\/jats:italic>\u2009=\u200935), a positive separation sign remained a reliable predictor of normal placental separation, with a positive predictive value of 100%, sensitivity of 88.9% (95%\u2009CI, 65.3\u201398.6%) and specificity of 100% (95%\u2009CI, 80.5\u2013100%).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>The separation sign could be a useful tool in women considered to be at risk for PAS, as it can facilitate the prediction of normal placental separation at delivery. This may prevent overtreatment, the associated iatrogenic morbidity and unnecessary allocation of clinical resources. \u00a9 2022 The Authors. <jats:italic>Ultrasound in Obstetrics &amp; Gynecology<\/jats:italic> published by John Wiley &amp; Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.<\/jats:p><\/jats:sec>","DOI":"10.1002\/uog.26021","type":"journal-article","created":{"date-parts":[[2022,7,15]],"date-time":"2022-07-15T07:20:33Z","timestamp":1657869633000},"page":"390-395","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Separation sign: novel ultrasound sign for ruling out diagnosis of placenta accreta spectrum"],"prefix":"10.1002","volume":"60","author":[{"given":"R. X.","family":"Allwood","sequence":"first","affiliation":[{"name":"The Medical Sciences Division University of Oxford  Oxford UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8846-9916","authenticated-orcid":false,"given":"A.","family":"Self","sequence":"additional","affiliation":[{"name":"The Fetal Medicine Unit John Radcliffe Hospital  Oxford UK"},{"name":"Nuffield Department of Women's and Reproductive Health University of Oxford  Oxford UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S. L.","family":"Collins","sequence":"additional","affiliation":[{"name":"The Fetal Medicine Unit John Radcliffe Hospital  Oxford UK"},{"name":"Nuffield Department of Women's and Reproductive Health University of Oxford  Oxford UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2022,9]]},"reference":[{"key":"e_1_2_7_2_1","doi-asserted-by":"publisher","DOI":"10.1111\/1471-0528.12405"},{"key":"e_1_2_7_3_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000001736"},{"key":"e_1_2_7_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2017.02.050"},{"key":"e_1_2_7_5_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.AOG.0000219750.79480.84"},{"key":"e_1_2_7_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-0412.2011.01147.x"},{"key":"e_1_2_7_7_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.19070"},{"issue":"443","key":"e_1_2_7_8_1","first-page":"e1","article-title":"Impact of targeted scanning protocols on perinatal outcomes in pregnancies at risk of placenta accreta spectrum or vasa previa","volume":"218","author":"Melcer Y","year":"2018","journal-title":"Am J Obstet Gynecol"},{"key":"e_1_2_7_9_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000002865"},{"key":"e_1_2_7_10_1","doi-asserted-by":"publisher","DOI":"10.1080\/110241501300091408"},{"key":"e_1_2_7_11_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000001113"},{"key":"e_1_2_7_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.placenta.2019.04.004"},{"key":"e_1_2_7_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.15810"},{"key":"e_1_2_7_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.13194"},{"key":"e_1_2_7_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2003.11.024"},{"key":"e_1_2_7_16_1","doi-asserted-by":"publisher","DOI":"10.1111\/aogs.13389"},{"key":"e_1_2_7_17_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.24804"},{"key":"e_1_2_7_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.2833"},{"key":"e_1_2_7_19_1","first-page":"773","article-title":"Prevalence of Sonographic Markers of Placenta Accreta Spectrum in Low\u2010Risk Pregnancies","volume":"36","author":"Philips J","year":"2019","journal-title":"Am J Perinatol"},{"key":"e_1_2_7_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/ijgo.12761"},{"key":"e_1_2_7_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/sim.2677"},{"key":"e_1_2_7_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.placenta.2011.11.010"},{"key":"e_1_2_7_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.bpobgyn.2020.08.004"},{"key":"e_1_2_7_24_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1471-0528.1990.tb01743.x"}],"container-title":["Ultrasound in Obstetrics &amp; Gynecology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.26021","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/uog.26021","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.26021","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,8,23]],"date-time":"2023-08-23T05:33:00Z","timestamp":1692768780000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/uog.26021"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9]]},"references-count":23,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2022,9]]}},"alternative-id":["10.1002\/uog.26021"],"URL":"https:\/\/doi.org\/10.1002\/uog.26021","archive":["Portico"],"relation":{},"ISSN":["0960-7692","1469-0705"],"issn-type":[{"value":"0960-7692","type":"print"},{"value":"1469-0705","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9]]},"assertion":[{"value":"2022-03-07","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-06-16","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-09-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}