{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T09:41:14Z","timestamp":1786527674113,"version":"build-2736575974"},"reference-count":21,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T00:00:00Z","timestamp":1786492800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background\/Objectives: Preeclampsia is a heterogeneous hypertensive disorder of pregnancy, and accessible hematologic indices may reflect maternal physiologic differences before the clinical syndrome becomes evident. This study evaluated whether the first-trimester hemoglobin-to-red cell distribution width (Hb\/RDW) ratio was associated with later documented preeclampsia and assessed its discrimination, relation to disease severity, and association with maternal\u2013neonatal outcomes in a tertiary-care cohort. Methods: This retrospective cohort study included 224 singleton pregnancies managed at a tertiary referral center between January 2024 and December 2025. Data extraction, anonymization, and analysis were performed after ethics approval (Approval No. 72; 2 March 2026). Participants were categorized as preeclampsia-negative (n = 131) or preeclampsia-positive (n = 93). Preeclampsia and severe features were defined according to American College of Obstetricians and Gynecologists criteria. The Hb\/RDW ratio was calculated from routine first-trimester complete blood count parameters obtained before clinical diagnosis or final outcome classification. ROC analysis, multivariable logistic regression, multicollinearity assessment, events-per-variable evaluation, calibration testing, and exploratory incremental discrimination analyses were performed. Results: The first-trimester Hb\/RDW ratio was higher in pregnancies later complicated by preeclampsia. Single-marker ROC analysis showed moderate discrimination (AUC = 0.687; bootstrap 95% CI: 0.618\u20130.755). At the 0.63 cut-off, sensitivity was 89.2%, specificity 47.3%, positive predictive value 54.6%, and negative predictive value 86.1%. In the primary multivariable model, Hb\/RDW remained associated with later preeclampsia (adjusted OR per 0.1-unit increase = 1.45; 95% CI: 1.22\u20131.72; p &lt; 0.001). However, Hb\/RDW was not independently associated with severe preeclampsia among affected patients, fetal growth restriction, or composite maternal morbidity. VIF values ranged from 1.00 to 1.07. Secondary models for fetal growth restriction and composite maternal morbidity had borderline events-per-variable values and were interpreted as exploratory. Conclusions: First-trimester Hb\/RDW was associated with later documented preeclampsia in this retrospective tertiary-care cohort, but its single-marker performance was modest and specificity was limited. The ratio should be interpreted as an inexpensive research marker of hematologic phenotype rather than a stand-alone screening, diagnostic, or management tool. Prospective multicenter validation with standardized first-trimester sampling and adjustment for hematinic and nutritional variables is required before clinical implementation.<\/jats:p>","DOI":"10.3390\/jcm15166234","type":"journal-article","created":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T09:11:36Z","timestamp":1786525896000},"page":"6234","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["First-Trimester Hemoglobin-to-RDW Ratio in Pregnancies Subsequently Complicated by Preeclampsia: Association, Discrimination, and Clinical Interpretability in a Retrospective Cohort"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9526-3828","authenticated-orcid":false,"given":"Murat","family":"Haksever","sequence":"first","affiliation":[{"name":"Department of Perinatology, Sanliurfa Training and Research Hospital, 63040 Sanliurfa, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0755-5338","authenticated-orcid":false,"given":"Deniz","family":"Ta\u015fdemir","sequence":"additional","affiliation":[{"name":"Department of Perinatology, Sanliurfa Training and Research Hospital, 63040 Sanliurfa, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3951-3503","authenticated-orcid":false,"given":"Selim","family":"Kandemir","sequence":"additional","affiliation":[{"name":"Department of Gynecologic Oncology, Sanliurfa Training and Research Hospital, 63040 Sanliurfa, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8729-1669","authenticated-orcid":false,"given":"Bekir","family":"Kahveci","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Sanliurfa Training and Research Hospital, 63040 Sanliurfa, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5866-1798","authenticated-orcid":false,"given":"Refaettin","family":"\u015eahin","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Istinye University Faculty of Medicine, Liv Hospital, 34517 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3574-6649","authenticated-orcid":false,"given":"Alp Koray","family":"Kinter","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Istinye University Faculty of Medicine, Liv Hospital, 34517 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3028-5804","authenticated-orcid":false,"given":"Sava\u015f","family":"\u00d6zdemir","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Recep Tayyip Erdogan University Faculty of Medicine, 53200 Rize, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8209-8248","authenticated-orcid":false,"given":"Atakan","family":"Tana\u00e7an","sequence":"additional","affiliation":[{"name":"Department of Perinatology, Ankara Bilkent City Hospital, University of Health Sciences, 06018 Ankara, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3833-0999","authenticated-orcid":false,"given":"Ismet","family":"Hortu","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ege University Faculty of Medicine, 35100 Izmir, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2856","DOI":"10.1161\/CIRCULATIONAHA.109.853127","article-title":"Preeclampsia, a disease of the maternal endothelium: The role of antiangiogenic factors and implications for later cardiovascular disease","volume":"123","author":"Powe","year":"2011","journal-title":"Circulation"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1146\/annurev-pathol-121808-102149","article-title":"Pathogenesis of preeclampsia","volume":"5","author":"Young","year":"2010","journal-title":"Annu. Rev. Pathol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"S32","DOI":"10.1016\/j.placenta.2008.11.009","article-title":"The two stage model of preeclampsia: Variations on the theme","volume":"30","author":"Roberts","year":"2009","journal-title":"Placenta"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1077","DOI":"10.1161\/01.HYP.0000187899.34379.b0","article-title":"Circulating angiogenic factors in the pathogenesis and prediction of preeclampsia","volume":"46","author":"Lam","year":"2005","journal-title":"Hypertension"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1038\/nm1429","article-title":"Soluble endoglin contributes to the pathogenesis of preeclampsia","volume":"12","author":"Venkatesha","year":"2006","journal-title":"Nat. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1056\/NEJMoa1414838","article-title":"Predictive value of the sFlt-1:PlGF ratio in women with suspected preeclampsia","volume":"374","author":"Zeisler","year":"2016","journal-title":"N. Engl. J. Med."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"(2020). Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222. Obstet. Gynecol., 135, e237\u2013e260.","DOI":"10.1097\/AOG.0000000000003891"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"030502","DOI":"10.11613\/BM.2018.030502","article-title":"Red blood cell distribution width in pregnancy: A systematic review","volume":"28","author":"Paliogiannis","year":"2018","journal-title":"Biochem. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1186\/s40885-019-0119-7","article-title":"Red cell distribution width and preeclampsia: A systematic review and meta-analysis","volume":"25","author":"Adam","year":"2019","journal-title":"Clin. Hypertens."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1186\/1746-1596-9-29","article-title":"Red blood cell distribution width is not correlated with preeclampsia among pregnant Sudanese women","volume":"9","author":"Abdullahi","year":"2014","journal-title":"Diagn. Pathol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1177\/1076029613490827","article-title":"Relationship of red cell distribution width with the presence and severity of preeclampsia","volume":"21","author":"Aras","year":"2015","journal-title":"Clin. Appl. Thromb. Hemost."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1016\/j.preghy.2016.05.001","article-title":"Red blood cell distribution width: A simple parameter in preeclampsia","volume":"6","author":"Yilmaz","year":"2016","journal-title":"Pregnancy Hypertens."},{"key":"ref_13","first-page":"e55910","article-title":"A case-control study utilizing red cell distribution width as a bio-inflammatory marker in pre-eclampsia","volume":"16","author":"Singhal","year":"2024","journal-title":"Cureus"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Meszaros, B.M., Veres, D.S., Nagyistok, L., Kovacs, B.G., Kukor, Z., and Valent, S. (2024). A meta-analysis on first-trimester blood count parameters-is the neutrophil-to-lymphocyte ratio a potentially novel method for first-trimester preeclampsia screening?. Front. Med., 11.","DOI":"10.3389\/fmed.2024.1336764"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e18496","DOI":"10.1097\/MD.0000000000018496","article-title":"Diagnostic value of neutrophil-lymphocyte ratio in preeclampsia: A PRISMA-compliant systematic review and meta-analysis","volume":"98","author":"Zheng","year":"2019","journal-title":"Medicine"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1553","DOI":"10.1002\/ijgo.70510","article-title":"Unraveling preeclampsia: Is the fibrinogen-to-albumin ratio the key to early risk assessment?","volume":"172","author":"Zorlu","year":"2026","journal-title":"Int. J. Gynaecol. Obstet."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1002\/ijgo.12802","article-title":"The International Federation of Gynecology and Obstetrics (FIGO) initiative on pre-eclampsia: A pragmatic guide for first-trimester screening and prevention","volume":"145","author":"Poon","year":"2019","journal-title":"Int. J. Gynaecol. Obstet."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1056\/NEJMoa1704559","article-title":"Aspirin versus placebo in pregnancies at high risk for preterm preeclampsia","volume":"377","author":"Rolnik","year":"2017","journal-title":"N. Engl. J. Med."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"473","DOI":"10.2217\/bmm-2021-0577","article-title":"Prognostic value of hemoglobin-to-red cell distribution width ratio in cancer: A systematic review and meta-analysis","volume":"16","author":"Chi","year":"2022","journal-title":"Biomark. Med."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Coradduzza, D., Zinellu, A., Mangoni, A.A., Angius, A., Carru, C., and De Miglio, M.R. (2023). Assessing the predictive power of the hemoglobin\/red cell distribution width ratio in cancer: A systematic review and future directions. Medicina, 59.","DOI":"10.3390\/medicina59122124"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Li, M., Li, H., Zhong, W., Wang, S., Liu, R., Cheng, H., Li, L., Wei, Q., and Wang, L. (2025). Hemoglobin-to-red cell distribution width ratio was associated with cardiovascular diseases and death. J. Clin. Med., 14.","DOI":"10.3390\/jcm14134464"}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/16\/6234\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T09:23:25Z","timestamp":1786526605000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/16\/6234"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,12]]},"references-count":21,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["jcm15166234"],"URL":"https:\/\/doi.org\/10.3390\/jcm15166234","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,12]]}}}