{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T05:53:29Z","timestamp":1791266009132,"version":"4.1.0"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2022,1,5]],"date-time":"2022-01-05T00:00:00Z","timestamp":1641340800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Norwegian Mother"},{"name":"Father and Child Cohort"},{"name":"Norwegian Ministry of Health and Care Services and the Ministry of Education and Research"},{"name":"Norwegian Research Council\u2019s Centres of Excellence Funding Scheme","award":["262700"],"award-info":[{"award-number":["262700"]}]},{"name":"Medical Research Council Integrative Epidemiology Unit at the University of Bristol"},{"name":"UK MRC","award":["MC_UU_00011\/3 and MC_UU_00011\/6"],"award-info":[{"award-number":["MC_UU_00011\/3 and MC_UU_00011\/6"]}]},{"DOI":"10.13039\/100000066","name":"National Institute of Environmental Health Sciences","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,6,13]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Maternal diabetes is a well-known risk factor for pregnancy complications. Possible links between long-term maternal blood sugar in the normal range and pregnancy complications are less well described.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We assayed glycated haemoglobin (HbA1c) in blood samples collected around the 18th week of pregnancy for 2937 singleton pregnancies in the Norwegian Mother, Father and Child Cohort Study (2000\u201309). Perinatal outcomes (gestational length, birthweight, birth length and head circumference, large-for-gestational age, small-for-gestational age, congenital malformations, preterm delivery and preeclampsia) were obtained from medical records. We tested associations using linear and log-binomial regression, adjusting for maternal age, body mass index (BMI) and smoking.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Size at birth increased modestly but linearly with HbA1c. Birthweight rose 0.10 standard deviations [95% confidence interval (CI): 0.03, 0.16], for each 5-mmol\/mol unit increase in HbA1c, corresponding to about 40 g at 40\u2009weeks of gestation. Large-for-gestational age rose 23% (95% CI: 1%, 50%) per five-unit increase. Other pregnancy complications increased in non-linear fashion, with strongest associations within the top quartile of HbA1c (&amp;gt;35\u2009mmol\/mol or &amp;gt;5.4%). Per unit HbA1c within the top quartile, preterm delivery increased by 14% (95% CI: 1%, 31%), preeclampsia increased by 20% (95% CI: 5%, 37%) and gestational duration decreased by 0.7\u2009days (95% CI: \u22121.0, \u22120.3).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Among women with no recorded diabetes, higher HbA1c levels at 18 gestational weeks were associated with important perinatal outcomes independent of mother\u2019s age, smoking or BMI.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ije\/dyab270","type":"journal-article","created":{"date-parts":[[2021,12,20]],"date-time":"2021-12-20T07:14:41Z","timestamp":1639984481000},"page":"759-768","source":"Crossref","is-referenced-by-count":21,"title":["Glycated haemoglobin (HbA1c) in mid-pregnancy and perinatal outcomes"],"prefix":"10.1093","volume":"51","author":[{"given":"Ellen \u00d8","family":"Carlsen","sequence":"first","affiliation":[{"name":"Centre for Fertility and Health, Norwegian Institute of Public Health , Oslo, Norway"},{"name":"Department of Community Medicine, Institute of Health and Society, University of Oslo , Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5866-848X","authenticated-orcid":false,"given":"Quaker","family":"Harmon","sequence":"additional","affiliation":[{"name":"Epidemiology Branch, National Institute of Environmental Health Sciences , Durham, NC, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria C","family":"Magnus","sequence":"additional","affiliation":[{"name":"Centre for Fertility and Health, Norwegian Institute of Public Health , Oslo, Norway"},{"name":"MRC Integrative Epidemiology Unit, University of Bristol , Bristol, UK"},{"name":"Population Health Sciences, Bristol Medical School , Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helle M","family":"Meltzer","sequence":"additional","affiliation":[{"name":"Division of Climate and Environment, Environment and Health, Norwegian Institute of Public Health , Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iris","family":"Erlund","sequence":"additional","affiliation":[{"name":"Department of Government Services (Biomarkers Team), Finnish Institute for Health and Welfare , Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars C","family":"Stene","sequence":"additional","affiliation":[{"name":"Department of Chronic Diseases and Ageing, Norwegian Institute of Public Health , Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2199-5225","authenticated-orcid":false,"given":"Siri E","family":"H\u00e5berg","sequence":"additional","affiliation":[{"name":"Centre for Fertility and Health, Norwegian Institute of Public Health , Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allen J","family":"Wilcox","sequence":"additional","affiliation":[{"name":"Epidemiology Branch, National Institute of Environmental Health Sciences , Durham, NC, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2022,1,5]]},"reference":[{"key":"2022061309575527300_dyab270-B1","doi-asserted-by":"crossref","first-page":"2271","DOI":"10.1001\/jama.2014.6342","article-title":"Interpretation of hemoglobin A1c values","volume":"311","author":"Sacks","year":"2014","journal-title":"JAMA"},{"key":"2022061309575527300_dyab270-B2","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/j.dsx.2012.05.010","article-title":"HbA1c in pregnancy","volume":"6","author":"Rafat","year":"2012","journal-title":"Diabetes Metab 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