{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T01:06:26Z","timestamp":1770858386580,"version":"3.50.1"},"reference-count":22,"publisher":"Georg Thieme Verlag KG","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Ultraschall Med"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Despite advances in diagnostic approaches, fetal anemia of unknown etiology continues to be observed in rare cases. This study aimed to assess the incidence of unexplained fetal anemia and to evaluate the associated perinatal outcomes.<\/jats:p>\n                  <jats:p>We conducted an observational retrospective cohort study of all fetuses that underwent fetal blood sampling (FBS) due to an MCA-PSV&gt;1.5 MoM at a tertiary center between 2007 and 2024. Fetuses were included if they had moderate or severe anemia defined as a hemoglobin (Hgb) deviation of more than 20g\/L below a gestational age adjusted mean, with a negative anemia workup. Prenatal and postnatal outcomes were obtained.<\/jats:p>\n                  <jats:p>Among 376 fetuses that underwent fetal blood sampling for anemia, 361 (96%) had an identified cause, while 15 (4%) had moderate to severe anemia of unknown etiology. Seven fetuses presented with non-immune hydrops and eight with other major structural anomalies not typically associated with anemia. Eleven (73%) of the 15 fetuses with unexplained anemia had thrombocytopenia, with platelets below 100000\/\u00b5L in 8 cases and below 50000\/\u00b5L in 6 cases. Seven cases (47%) resulted in perinatal death. Rare causes of anemia were elucidated in only 5 cases (33%) postnatally despite extensive investigations.<\/jats:p>\n                  <jats:p>Unexplained fetal anemia is uncommon and is associated with poor neonatal outcomes warranting close pre- and postnatal surveillance.<\/jats:p>","DOI":"10.1055\/a-2773-2240","type":"journal-article","created":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T00:18:17Z","timestamp":1765844297000},"source":"Crossref","is-referenced-by-count":0,"title":["Causes and outcomes of prenatally unexplained fetal anemia"],"prefix":"10.1055","author":[{"given":"Saja","family":"Anabusi","sequence":"first","affiliation":[{"name":"Ontario Fetal Centre, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynaecology, Mount Sinai Hospital, University of Toronto, Toronto, Canada"},{"name":"Maternal Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Saint John Regional Hospital, Saint John, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charles","family":"Litwin","sequence":"first","affiliation":[{"name":"Ontario Fetal Centre, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynaecology, Mount Sinai Hospital, University of Toronto, Toronto, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Greg","family":"Ryan","sequence":"additional","affiliation":[{"name":"Ontario Fetal Centre, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynaecology, Mount Sinai Hospital, University of Toronto, Toronto, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Chitayat","sequence":"additional","affiliation":[{"name":"The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, Toronto, Canada"},{"name":"Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiri","family":"Shinar","sequence":"additional","affiliation":[{"name":"Ontario Fetal Centre, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynaecology, Mount Sinai Hospital, University of Toronto, Toronto, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"194","published-online":{"date-parts":[[2026,2,11]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1721","DOI":"10.1111\/J.1537-2995.2008.01742.X,","article-title":"One single dose of 200 \u03bcg of antenatal RhIG halves the risk of anti-D immunization and hemolytic disease of the fetus and newborn in the next pregnancy","volume":"48","author":"JM Koelewijn","year":"2008","journal-title":"Transfusion (Paris)"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"129","DOI":"10.1016\/S0887-7963(88)70039-5","article-title":"The Prevention of Rh Immunization","volume":"2","author":"JM Bowman","year":"1988","journal-title":"Transfus Med Rev"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"289","DOI":"10.1016\/0002-9378(85)90288-1,","article-title":"Controversies in Rh prophylaxis. 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Use of a new developed Free DNA Fetal Kit RhD","volume":"14","author":"C Rouillac-Le Sciellour","year":"2007","journal-title":"Transfusion Clinique et Biologique"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"417","DOI":"10.1016\/j.ajog.2024.03.044","article-title":"Intravenous immunoglobulin for the treatment of severe maternal alloimmunization: individual patient data meta-analysis","volume":"231","author":"HJ Mustafa","year":"2024","journal-title":"Am J Obstet Gynecol"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"526","DOI":"10.1056\/NEJMOA2314466,","article-title":"Nipocalimab in Early-Onset Severe Hemolytic Disease of the Fetus and Newborn","volume":"391","author":"KJ Moise","year":"2024","journal-title":"New England Journal of Medicine"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"697","DOI":"10.1016\/j.ajog.2015.01.059","article-title":"Society for Maternal-Fetal Medicine (SMFM) Clinical Guideline #8: The fetus at risk for anemia-diagnosis and management","volume":"212","author":"G Mari","year":"2015","journal-title":"Am J Obstet Gynecol"},{"key":"ref11","doi-asserted-by":"publisher","DOI":"10.1055\/S-0031-1281756,","article-title":"Fetal anemia of unknown cause a diagnostic challenge","volume":"32","author":"C Amann","year":"2011","journal-title":"Ultraschall in Med"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"156","DOI":"10.1159\/000501554,","article-title":"Managing the Unusual Causes of Fetal Anemia","volume":"47","author":"E Maisonneuve","year":"2020","journal-title":"Fetal Diagn Ther"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"1073","DOI":"10.1016\/S0140-6736(88)91896-X","article-title":"Fetal haemoglobin measurement in the assessment of red cell isoimmunization","volume":"331","author":"KH Nicolaides","year":"1988","journal-title":"The Lancet"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"550","DOI":"10.1159\/000540342","article-title":"Elevated Middle Cerebral Artery Peak Systolic Velocity in Non-Anemic Fetuses: Providing a Better Understanding of Enigmatic Middle Cerebral Artery Peak Systolic Velocity","volume":"51","author":"S Anabusi","year":"2024","journal-title":"Fetal Diagn Ther"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"740","DOI":"10.1111\/J.1471-0528.1990.TB16250.X,","article-title":"Maternal abdominal pressure alters fetal cerebral blood flow","volume":"97","author":"S Vyas","year":"1990","journal-title":"BJOG"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"432","DOI":"10.1002\/UOG.1010,","article-title":"Prediction of fetal anemia in rhesus disease by measurement of fetal middle cerebral artery peak systolic velocity","volume":"23","author":"M Scheier","year":"2004","journal-title":"Ultrasound in Obstetrics and Gynecology"},{"key":"ref17","doi-asserted-by":"publisher","DOI":"10.1126\/SCIADV.AAX0021,","article-title":"Deficient histone H3 propionylation by BRPF1-KAT6 complexes in neurodevelopmental disorders and cancer","volume":"6","author":"K Yan","year":"2020","journal-title":"Sci Adv"},{"key":"ref18","doi-asserted-by":"publisher","first-page":"1498","DOI":"10.3109\/14767058.2010.551149,","article-title":"Managing the difficult case of fetal anemia","volume":"24","author":"EG Zhang","year":"2011","journal-title":"Journal of Maternal-Fetal and Neonatal Medicine"},{"key":"ref19","doi-asserted-by":"publisher","DOI":"10.1097\/MPH.0B013E31821B368C,","article-title":"In utero diagnosis and management of a fetus with homozygous \u03b1-thalassemia in the second trimester: A case report and literature review","volume":"33","author":"SJ Dwinnell","year":"2011","journal-title":"J Pediatr Hematol Oncol"},{"key":"ref20","doi-asserted-by":"publisher","DOI":"10.1002\/PD.6630","article-title":"Acute fetal leukemia: When should it be suspected? What assessment should be performed? A case series and review of literature","author":"PL Forey","year":"2024","journal-title":"Prenat Diagn"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"440","DOI":"10.1055\/A-2524-5787","article-title":"Intrauterine Therapy","volume":"46","author":"I Gottschalk","year":"2025","journal-title":"Ultraschall in Med"},{"key":"ref22","doi-asserted-by":"publisher","first-page":"E83","DOI":"10.1055\/A-1499-7045","article-title":"Fetal Hemodynamic Response to Anemia in Early Gestation: Using Hemoglobin Bart\u2019s Disease as a Study Model","volume":"44","author":"S Luewan","year":"2023","journal-title":"Ultraschall in Med"}],"container-title":["Ultraschall in der Medizin - European Journal of Ultrasound"],"original-title":[],"language":"de","link":[{"URL":"http:\/\/www.thieme-connect.de\/products\/ejournals\/pdf\/10.1055\/a-2773-2240.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T00:20:00Z","timestamp":1770855600000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.thieme-connect.de\/DOI\/DOI?10.1055\/a-2773-2240"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,15]]},"references-count":22,"URL":"https:\/\/doi.org\/10.1055\/a-2773-2240","archive":["Portico","CLOCKSS"],"relation":{},"ISSN":["0172-4614","1438-8782"],"issn-type":[{"value":"0172-4614","type":"print"},{"value":"1438-8782","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2025,12,15]]},"published":{"date-parts":[[2025,12,15]]}}}