{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T06:20:48Z","timestamp":1780726848339,"version":"3.54.1"},"reference-count":19,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2015,3,3]],"date-time":"2015-03-03T00:00:00Z","timestamp":1425340800000},"content-version":"vor","delay-in-days":2,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Ultrasound in Obstet &amp;amp; Gyne"],"published-print":{"date-parts":[[2015,3]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Objectives<\/jats:title><jats:p>To examine the distribution of cervical length (<jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content>) in the late second and third trimesters of pregnancy and construct survival models for spontaneous delivery.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>This cross\u2010sectional study included 647 women with a singleton pregnancy who had routine <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> measurements taken by transvaginal ultrasonography between 24 and 40 weeks' gestation. Only one measurement per patient was included in the analysis. Exploratory data analysis revealed that the distribution of <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> measurements was a mixture of two Gaussian distributions, and subsequently a mixture model was applied to describe the distribution of <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content>. Changes in <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> in relation to gestational age were examined by regression analysis and measurements were converted to <jats:italic>Z<\/jats:italic>\u2010scores. Survival analysis was applied to the subgroups identified, to describe the probability of delivery throughout gestation.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p><jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> was best described by a mixture model of two subgroups with Gaussian distribution, one including women with a long cervix (73.85% of the study population, mean <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> of 28.2\u2009\u00b1\u20094.45\u2009mm) and the other including women with a short cervix (26.15% of the study population, mean <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> of 12.3\u2009\u00b1\u20095.14\u2009mm). <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> was dependent on gestational age (<jats:styled-content style=\"fixed-case\">GA<\/jats:styled-content>), therefore conversion to <jats:italic>Z<\/jats:italic>\u2010scores was employed in the analysis. Women with a short cervix had a higher probability for spontaneous delivery (hazard ratio (<jats:styled-content style=\"fixed-case\">HR<\/jats:styled-content>), 1.807; <jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001) than did women with a long cervix, after adjustment for <jats:styled-content style=\"fixed-case\">GA<\/jats:styled-content> at the time of measurement (GA <jats:styled-content style=\"fixed-case\">HR<\/jats:styled-content>, 1.115; <jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001). In both subgroups, the probability of spontaneous delivery was predicted by the <jats:styled-content style=\"fixed-case\">GA<\/jats:styled-content> and <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> <jats:italic>Z<\/jats:italic>\u2010scores. Survival models for the prediction of spontaneous delivery were constructed separately for the short\u2010cervix subgroup (<jats:styled-content style=\"fixed-case\">GA HR<\/jats:styled-content>, 1.085; <jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001 and <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> <jats:italic>Z<\/jats:italic>\u2010score <jats:styled-content style=\"fixed-case\">HR<\/jats:styled-content>, 0.819; <jats:italic>P<\/jats:italic>\u2009=\u20090.003) and the long\u2010cervix subgroup (<jats:styled-content style=\"fixed-case\">GA HR<\/jats:styled-content>, 1.130; <jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001 and <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> Z\u2010score <jats:styled-content style=\"fixed-case\">HR<\/jats:styled-content>, 0.864; <jats:italic>P<\/jats:italic>\u2009=\u20090.005).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p><jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> follows a mixture of two Gaussian distributions, one for a short and one for a long cervix. Late second\u2010trimester\/third\u2010trimester <jats:styled-content style=\"fixed-case\">CL<\/jats:styled-content> measurement may be of value in estimating the probability for spontaneous delivery at any given gestational age. Copyright \u00a9 2014 ISUOG. Published by John Wiley &amp; Sons Ltd.<\/jats:p><\/jats:sec>","DOI":"10.1002\/uog.13407","type":"journal-article","created":{"date-parts":[[2014,5,10]],"date-time":"2014-05-10T14:18:40Z","timestamp":1399731520000},"page":"308-312","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Cervical length in late second and third trimesters: a mixture model for predicting delivery"],"prefix":"10.1002","volume":"45","author":[{"given":"A. P.","family":"Souka","sequence":"first","affiliation":[{"name":"Fetal Medicine Unit, 3rd Department of Obstetrics and Gynaecology University of Athens, \u2018Attikon\u2019 University Hospital  Athens Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"I.","family":"Papastefanou","sequence":"additional","affiliation":[{"name":"Fetal Medicine Unit, 3rd Department of Obstetrics and Gynaecology University of Athens, \u2018Attikon\u2019 University Hospital  Athens Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G.","family":"Papadopoulos","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics Agricultural University of Athens  Athens Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"Chrelias","sequence":"additional","affiliation":[{"name":"Fetal Medicine Unit, 3rd Department of Obstetrics and Gynaecology University of Athens, \u2018Attikon\u2019 University Hospital  Athens Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D.","family":"Kassanos","sequence":"additional","affiliation":[{"name":"Fetal Medicine Unit, 3rd Department of Obstetrics and Gynaecology University of Athens, \u2018Attikon\u2019 University Hospital  Athens Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2015,3,3]]},"reference":[{"key":"e_1_2_5_2_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1469-0705.1998.12050312.x"},{"key":"e_1_2_5_3_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa067815"},{"key":"e_1_2_5_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.9017"},{"key":"e_1_2_5_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(12)60030-0"},{"key":"e_1_2_5_6_1","doi-asserted-by":"publisher","DOI":"10.7863\/jum.2011.30.7.997"},{"key":"e_1_2_5_7_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.2640"},{"key":"e_1_2_5_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.2683"},{"key":"e_1_2_5_9_1","doi-asserted-by":"publisher","DOI":"10.1159\/000335686"},{"key":"e_1_2_5_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.12465"},{"key":"e_1_2_5_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.4158"},{"key":"e_1_2_5_12_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.4018"},{"key":"e_1_2_5_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.2746"},{"key":"e_1_2_5_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.2723"},{"key":"e_1_2_5_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.5291"},{"key":"e_1_2_5_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.5299"},{"key":"e_1_2_5_17_1","doi-asserted-by":"publisher","DOI":"10.1159\/000337322"},{"key":"e_1_2_5_18_1","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2393-10-37"},{"key":"e_1_2_5_19_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.2658"},{"key":"e_1_2_5_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.2685"}],"container-title":["Ultrasound in Obstetrics &amp; Gynecology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fuog.13407","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fuog.13407","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.13407","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,9,23]],"date-time":"2023-09-23T19:32:06Z","timestamp":1695497526000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/uog.13407"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,3]]},"references-count":19,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2015,3]]}},"alternative-id":["10.1002\/uog.13407"],"URL":"https:\/\/doi.org\/10.1002\/uog.13407","archive":["Portico"],"relation":{},"ISSN":["0960-7692","1469-0705"],"issn-type":[{"value":"0960-7692","type":"print"},{"value":"1469-0705","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,3]]},"assertion":[{"value":"2013-12-17","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2014-04-25","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2015-03-03","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}