{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:36:56Z","timestamp":1787618216336,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T00:00:00Z","timestamp":1757980800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Neonatology and the Department of Obstetrics, Charit\u00e9-Universit\u00e4tsmedizin Berlin, Germany"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The endogenous human retroviral protein syncytin-1 is vital for placental integrity via syncytiotrophoblast formation. Preeclampsia has been associated with reduced placental syncytin-1 expression. The goal of the prospective pilot study was to investigate the role of circulating fetal syncytin-1 mRNA in women with and without preeclampsia (PE). We therefore determined syncytin-1 mRNA in maternal plasma of n = 26 women without and n = 43 women with PE with quantitative real-time PCR. Median circulating syncytin-1 mRNA concentrations were significantly lower in women with PE [1 217 050 copies; IQR 610 900\u20131 482 069] vs. those without PE [1 992 739 copies; IQR 1 616 811\u20133 126 225], p &lt; 0.001. The area under the receiver operating curve used to diagnose PE at the time of delivery was 0.913 (95% CI: 0.850\u20130.977). Sub-analysis of patients with PE at sampling and patients who later developed PE vs. gestational-age-matched controls yielded a diagnostic accuracy of fetal syncytin-1 expression with an AUC of 0.962 (95% CI 0.877\u20131.000) and a predictive accuracy of 0.924 (95% CI 0.842\u20130.983). Quantification of the fetal syncytin-1 expression in maternal plasma might be used as a diagnostic and predictive tool in PE.<\/jats:p>","DOI":"10.3390\/ijms26189015","type":"journal-article","created":{"date-parts":[[2025,9,17]],"date-time":"2025-09-17T05:59:51Z","timestamp":1758088791000},"page":"9015","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Circulating Plasma Syncytin-1 mRNA in Preeclampsia\u2014A Pilot Study"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9298-3442","authenticated-orcid":false,"given":"Lisa","family":"Lorenz-Meyer","sequence":"first","affiliation":[{"name":"Department of Obstetrics, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9950-414X","authenticated-orcid":false,"given":"Christoph","family":"B\u00fchrer","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Verlohren","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4030-7969","authenticated-orcid":false,"given":"Stefanie","family":"Endesfelder","sequence":"additional","affiliation":[{"name":"Department of Neonatology, Charit\u00e9\u2014Universit\u00e4tsmedizin Berlin, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e626","DOI":"10.1016\/S2214-109X(24)00560-6","article-title":"Global and regional causes of maternal deaths 2009-20: A WHO systematic analysis","volume":"13","author":"Cresswell","year":"2025","journal-title":"Lancet Glob. 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