{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T22:26:29Z","timestamp":1787091989571,"version":"build-2736575974"},"reference-count":17,"publisher":"Wiley","issue":"2","license":[{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Ultrasound in Obstet &amp;amp; Gyne"],"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To evaluate the outcome of monochorionic diamniotic (MCDA) pregnancies complicated by twin reversed arterial perfusion (TRAP) sequence and to evaluate potential prognostic ultrasound markers as predictors of pump\u2010twin survival.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This was a retrospective cohort study of MCDA twin pregnancies diagnosed with TRAP sequence at two medical centers in China between January 2010 and December 2024. All cases were analyzed retrospectively for intrauterine course and outcome. Cases that underwent expectant management were assigned to the primary cohort (cases from the First Affiliated Hospital of Sun Yat\u2010sen University, Guangzhou) or the external\u2010validation cohort (cases from Dalian Women and Children's Medical Group, Dalian). Cases that underwent intrauterine intervention at the First Affiliated Hospital of Sun Yat\u2010sen University were assigned to the intrauterine\u2010intervention cohort. The following parameters were evaluated in the primary and external\u2010validation cohorts for their predictive value regarding pump\u2010twin survival: in the first trimester, the crown\u2013rump length (CRL) and nuchal translucency thickness of the pump twin, the upper pole\u2013rump length (URL) of the acardiac twin, the URL\/CRL ratio, and the presence of reversed a\u2010wave in the ductus venosus and the umbilical artery pulsatility index (UA\u2010PI) in the acardiac twin; and in the second trimester, the URL of the acardiac twin, the estimated fetal weight (EFW) of each twin, the twin weight ratio (TWR) (EFW\n                      <jats:sub>acardiac twin<\/jats:sub>\n                      \/EFW\n                      <jats:sub>pump twin<\/jats:sub>\n                      ) and the UA\u2010PI of each twin. Univariate Cox regression analysis was performed to identify the parameters associated with pump\u2010twin survival. Performance was evaluated by the area under the receiver\u2010operating\u2010characteristics curves (AUCs) and calibration curves. Finally, Kaplan\u2013Meier survival analysis was performed.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 117 MCDA pregnancies with TRAP sequence were included in the analysis: 55 in the primary cohort, 38 in the intrauterine\u2010intervention cohort and 24 in the external\u2010validation cohort. The overall pump\u2010twin survival rate was 65.8% (77\/117). Three variables (URL and URL\/CRL ratio in the first trimester and TWR in the second trimester) were identified to be independent risk factors influencing pump\u2010twin survival in both the primary and external\u2010validation cohorts. The AUCs were indicative of good predictive discrimination in both cohorts: 0.811 (95%\u00a0CI, 0.667\u20130.956) for URL, 0.780 (95%\u00a0CI, 0.619\u20130.941) for the URL\/CRL ratio and 0.859 (95%\u00a0CI, 0.730\u20130.988) for TWR in the primary cohort; and 0.844 (95%\u00a0CI, 0.662\u20131.000) for URL, 0.823 (0.633\u20131.000) for the URL\/CRL ratio and 0.925 (95%\u00a0CI, 0.766\u20131.000) for TWR in the external\u2010validation cohort. The optimal cut\u2010off values were 4.85\u2009cm for URL, 0.54 for the URL\/CRL ratio and 0.295 for TWR in the primary cohort. The TWR exhibited good calibration, but URL and the URL\/CRL ratio exhibited poor calibration. Kaplan\u2013Meier survival analysis revealed that pump twins with TWR\u2009\u2265\u20090.295 experienced a significantly shorter intrauterine survival duration in both the primary and external\u2010validation cohorts, and pump twins with URL \u2265\u20094.85\u2009cm or URL\/CRL ratio \u2265\u20090.54 experienced a significantly shorter intrauterine survival duration in the primary cohort. However, the optimal cut\u2010offs of URL and the URL\/CRL ratio showed no statistical difference in the external\u2010validation cohort.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>After 14\u2009+\u20090\u2009weeks' gestation, the threshold of TWR &lt;\u20090.295 can reliably predict survival of the pump twin in MCDA pregnancies with TRAP sequence. However, the predictive value of URL and the URL\/CRL ratio in the first trimester for pump\u2010twin survival is poor. A well\u2010designed prospective multicenter study is warranted to develop a first\u2010trimester multivariable predictive model with enhanced predictive performance. \u00a9 2026 International Society of Ultrasound in Obstetrics and Gynecology.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/uog.70256","type":"journal-article","created":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T16:56:11Z","timestamp":1784307371000},"page":"220-228","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development and external validation of prognostic markers to predict pump\u2010twin survival in twin reversed arterial perfusion sequence"],"prefix":"10.1002","volume":"68","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0354-3396","authenticated-orcid":false,"given":"L.\u2010H.","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y.\u2010Y.","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9576-2619","authenticated-orcid":false,"given":"H.","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5049-2267","authenticated-orcid":false,"given":"L.","family":"Du","sequence":"additional","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y.","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Ultrasound Dalian Women and Children's Medical Group  Dalian China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R.","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1705-1328","authenticated-orcid":false,"given":"H.\u2010N.","family":"Xie","sequence":"additional","affiliation":[{"name":"Department of Ultrasonic Medicine First Affiliated Hospital of Sun Yat\u2010sen University  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,7,17]]},"reference":[{"key":"e_1_2_6_2_1","doi-asserted-by":"publisher","DOI":"10.1002\/bdra.23405"},{"key":"e_1_2_6_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/pd.1269"},{"key":"e_1_2_6_4_1","doi-asserted-by":"publisher","DOI":"10.1053\/j.semperi.2014.10.005"},{"key":"e_1_2_6_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2012.09.025"},{"key":"e_1_2_6_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9378(90)91094-S"},{"key":"e_1_2_6_7_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2010.04.018"},{"key":"e_1_2_6_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.16013"},{"key":"e_1_2_6_9_1","doi-asserted-by":"publisher","DOI":"10.1159\/000295176"},{"key":"e_1_2_6_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.12495"},{"key":"e_1_2_6_11_1","doi-asserted-by":"publisher","DOI":"10.1055\/a-1526-1775"},{"key":"e_1_2_6_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.bpobgyn.2022.03.006"},{"key":"e_1_2_6_13_1","doi-asserted-by":"publisher","DOI":"10.1111\/jebm.12488"},{"key":"e_1_2_6_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9378(85)90298-4"},{"key":"e_1_2_6_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/tera.1420500306"},{"key":"e_1_2_6_16_1","doi-asserted-by":"publisher","DOI":"10.1097\/00006250-199909000-00017"},{"key":"e_1_2_6_17_1","doi-asserted-by":"publisher","DOI":"10.1067\/S0002-9378(03)00597-0"},{"issue":"44","key":"e_1_2_6_18_1","first-page":"181","article-title":"Ultrasound imaging of acardia blood spontaneously blocked before and after and pump twin outcome in twin reversed arterial perfusion sequence","volume":"10","author":"Chen X","year":"2014","journal-title":"Ultrasound Obstet Gynecol"}],"container-title":["Ultrasound in Obstetrics &amp; Gynecology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.70256","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/uog.70256","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.70256","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T21:49:03Z","timestamp":1787089743000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/uog.70256"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,17]]},"references-count":17,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,8]]}},"alternative-id":["10.1002\/uog.70256"],"URL":"https:\/\/doi.org\/10.1002\/uog.70256","archive":["Portico"],"relation":{},"ISSN":["0960-7692","1469-0705"],"issn-type":[{"value":"0960-7692","type":"print"},{"value":"1469-0705","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,17]]},"assertion":[{"value":"2025-11-05","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-04-28","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-17","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}