{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T18:24:41Z","timestamp":1790360681527,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,8]],"date-time":"2021-05-08T00:00:00Z","timestamp":1620432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>To evaluate whether women with anaemia or high haemoglobin (Hb) in early pregnancy would be at higher risk of miscarriage, this population-based cohort study involved 9453 women whose pregnancies were monitored at primary care centres between 2007 and 2012. The computerised clinical histories were used to collect: Hb measurements (up to 14 weeks of gestation), miscarriage before or by 24 weeks of gestation, and other maternal characteristics. The relation between anaemia (Hb &lt; 110 g\/L), normal Hb (110\u2013140 g\/L, reference), and high Hb concentrations (\u2265140 g\/L) with miscarriage were expressed as adjusted OR with 95%CI. Restricted cubic spline models were applied to evaluate the dose-response relationships. A total of 520 (5.5%) women were recorded as having a miscarriage. The rate of miscarriage in anaemia, normal Hb, and high Hb concentrations was 8.4%, 5.1%, and 10.2%, respectively. Compared with women with normal Hb at the first trimester, the multivariable-adjusted OR for miscarriage was 2.11 (95%CI, 1.38\u20133.21) for women with anaemia and 1.83 (95%CI, 1.29\u20132.58) for women with high Hb. Hb concentrations showed a U-shaped association with miscarriage, with the lowest incidence among women with Hb of 120\u2013130 g\/L. These data highlight the importance of considering anaemia and high Hb levels in early pregnancy as harmful indicators for miscarriage.<\/jats:p>","DOI":"10.3390\/nu13051578","type":"journal-article","created":{"date-parts":[[2021,5,10]],"date-time":"2021-05-10T02:54:58Z","timestamp":1620615298000},"page":"1578","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["High and Low Haemoglobin Levels in Early Pregnancy Are Associated to a Higher Risk of Miscarriage: A Population-Based Cohort Study"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7500-5629","authenticated-orcid":false,"given":"Andr\u00e9s","family":"D\u00edaz-L\u00f3pez","sequence":"first","affiliation":[{"name":"Serra Hunter Fellow, Universitat Rovira i Virgili (URV), 43201 Reus, Spain"},{"name":"Nutrition and Mental Health Research Group (NUTRISAM), Rovira i Virgili University (URV), 43201 Reus, Spain"},{"name":"Institut d\u2019Investigaci\u00f3 Sanit\u00e0ria Pere Virgili (IISPV), 43003 Reus, Spain"},{"name":"CIBER of Pathophysiology of Obesity and Nutrition (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3334-0602","authenticated-orcid":false,"given":"Blanca","family":"Ribot","sequence":"additional","affiliation":[{"name":"Nutrition and Mental Health Research Group (NUTRISAM), Rovira i Virgili University (URV), 43201 Reus, Spain"},{"name":"Institut d\u2019Investigaci\u00f3 Sanit\u00e0ria Pere Virgili (IISPV), 43003 Reus, Spain"},{"name":"Research Group on Methodology, Methods, Models and Outcomes of Health and Social Sciences (M3O), Faculty of Health Sciences and Welfare, Centre for Health and Social Care Research (CESS), University of Vic-Central University of Catalonia (UVIC-UCC), 08500 Vic, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josep","family":"Basora","sequence":"additional","affiliation":[{"name":"Unitat de Suport a la Recerca Tarragona-Reus, Fundaci\u00f3 Institut Universitari per a la Recerca a l\u2019Atenci\u00f3 Prim\u00e0ria de Salut Jordi Gol i Gurina (IDIAPJGol), 43202 Reus, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1758-0975","authenticated-orcid":false,"given":"Victoria","family":"Arija","sequence":"additional","affiliation":[{"name":"Nutrition and Mental Health Research Group (NUTRISAM), Rovira i Virgili University (URV), 43201 Reus, Spain"},{"name":"Institut d\u2019Investigaci\u00f3 Sanit\u00e0ria Pere Virgili (IISPV), 43003 Reus, Spain"},{"name":"Unitat de Suport a la Recerca Tarragona-Reus, Fundaci\u00f3 Institut Universitari per a la Recerca a l\u2019Atenci\u00f3 Prim\u00e0ria de Salut Jordi Gol i Gurina (IDIAPJGol), 43202 Reus, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,8]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2006). 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