{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T13:40:53Z","timestamp":1790948453374,"version":"4.1.0"},"reference-count":38,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2025,5,9]],"date-time":"2025-05-09T00:00:00Z","timestamp":1746748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Placental dysfunction is important to recognize, and more evidence is needed on the dynamics of the placental biomarkers, soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF), in early pregnancy. This study aimed to establish reference intervals for placental biomarkers in early pregnancy.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>This was a retrospective cohort study of pregnant women (n = 702) in the North Denmark Region, 2013, who had blood samples drawn in early pregnancy including measurements of sFlt-1 and PlGF (Kryptor Compact, Thermofisher Scientific). Reference intervals were established, and the association between sFlt-1 and PlGF and maternal characteristics (age, body mass index [BMI], country of birth, and smoking in pregnancy) was evaluated using linear regression analyses and reported as adjusted beta coefficient (a\u03b2) with 95% confidence intervals (CIs).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>The placental biomarkers showed a dynamic trend with higher levels for increasing week of pregnancy; however, sFlt-1 reached a plateau around week 10 of pregnancy. Higher maternal age associated with higher sFlt-1 and PlGF (sFlt-1: a\u03b2 1.02 [95% CI, 1.01\u20131.03], PlGF: a\u03b2 1.02 [95% CI, 1.01\u20131.03]), and higher maternal BMI associated with lower sFlt-1 (a\u03b2 0.97 [95% CI, 0.96\u20130.98]). Furthermore, the level of PlGF was higher among women born outside of Denmark (a\u03b2 1.17 [95% CI, 1.03\u20131.34]) compared to women born in Denmark and among smokers (a\u03b2 1.56 [95% CI, 1.38\u20131.78]) compared to nonsmokers.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>In a large cohort of pregnant women in Denmark, levels of sFlt-1 and PlGF increased during early pregnancy and were influenced by a series of maternal characteristics.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jalm\/jfaf064","type":"journal-article","created":{"date-parts":[[2025,4,17]],"date-time":"2025-04-17T09:33:43Z","timestamp":1744882423000},"page":"949-962","source":"Crossref","is-referenced-by-count":1,"title":["Reference Intervals for Placental Biomarkers in Early Pregnancy"],"prefix":"10.1093","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-6031-0137","authenticated-orcid":false,"given":"Maja Hjelm","family":"Lundgaard","sequence":"first","affiliation":[{"name":"Department of Clinical Biochemistry, Aalborg University Hospital , Aalborg ,","place":["Denmark"]},{"name":"Department of Clinical Medicine, Aalborg University , Aalborg ,","place":["Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niels Henrik","family":"Bruun","sequence":"additional","affiliation":[{"name":"Research Data and Biostatistics, Aalborg University , Aalborg ,","place":["Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5719-203X","authenticated-orcid":false,"given":"Aase","family":"Handberg","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, Aalborg University Hospital , Aalborg ,","place":["Denmark"]},{"name":"Department of Clinical Medicine, 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