{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T14:43:32Z","timestamp":1769525012030,"version":"3.49.0"},"reference-count":69,"publisher":"BMJ","issue":"10","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2017,8,17]]},"published-print":{"date-parts":[[2017,10]]},"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To estimate the association between maternal body mass index (BMI) and risk of spontaneous preterm delivery (sPTD) and elective preterm delivery (ePTD) in singleton and multiple pregnancies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Retrospective cohort study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>Electronic records of all deliveries from 2009 through 2013 in a tertiary university hospital were abstracted for demographic and obstetrical information.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>A total of 38\u2009528 deliveries were included. Participants with missing data were excluded from the study. BMI was calculated from the measurement of height and weight at the first prenatal visit and categorised. Sonographic confirmation of gestational age was standard.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Outcome measures<\/jats:title>\n                    <jats:p>Primary outcomes, sPTD and ePTD in singleton and multiple pregnancies, were evaluated by multinomial logistic regression analyses, stratified by parity, controlling for confounding variables.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Overall rate of PTD was 5.9%, from which 2.7% were sPTD and 3.2% ePTD. The rate of PTD was 50.4% in multiple pregnancies and 5.0% in singleton pregnancies. The risk of sPTD was increased in obese nulliparas (adjusted OR (aOR) 2.8, 95%\u2009CI 1.7 to 4.4) and underweight multiparas (aOR 2.2, 95%\u2009CI 1.3 to 3.8). The risk of ePTD was increased in underweight nulliparas (aOR 1.8; 95%\u2009CI 1.04 to 3.4) and severely obese multiparas (aOR 1.4, 95%\u2009CI 1.02 to 3.8).<\/jats:p>\n                    <jats:p>Severe obesity increased the risk of both sPTD (aOR 1.4; 95%\u2009CI 1.01 to 2.1) and ePTD (aOR 1.4; 95%\u2009CI 1.1 to 1.8) in singleton pregnancies. Obesity did not influence the rate of either sPTD or ePTD in multiple pregnancies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Maternal obesity is an independent risk factor for PTD in singleton pregnancies but not in multiple pregnancies. Obesity and nulliparity increase the risk of sPTD, whereas obesity and multiparity increase the risk of ePTD.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2016-015258","type":"journal-article","created":{"date-parts":[[2017,10,16]],"date-time":"2017-10-16T02:00:20Z","timestamp":1508119220000},"page":"e015258","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":23,"title":["Maternal body mass index and the prevalence of spontaneous and elective preterm deliveries in an Irish obstetric population: a retrospective cohort study"],"prefix":"10.1136","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2432-2616","authenticated-orcid":false,"given":"Angela","family":"Vinturache","sequence":"first","affiliation":[{"name":"Centre for Human Reproduction, University College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aoife","family":"McKeating","sequence":"additional","affiliation":[{"name":"Centre for Human Reproduction, University College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Niamh","family":"Daly","sequence":"additional","affiliation":[{"name":"Centre for Human Reproduction, University College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sharon","family":"Sheehan","sequence":"additional","affiliation":[{"name":"Centre for Human Reproduction, University College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Turner","sequence":"additional","affiliation":[{"name":"Centre for Human Reproduction, University College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2017,10,15]]},"reference":[{"key":"2025121221282956000_7.10.e015258.1","unstructured":"Institute of Medicine\u00a0. Leading health indicators for healthy people 2020:\u00a0letter report. Washington (DC): The National Academies Press\u00a0, 2011."},{"key":"2025121221282956000_7.10.e015258.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(12)60820-4"},{"key":"2025121221282956000_7.10.e015258.3","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2393-10-S1-S1"},{"key":"2025121221282956000_7.10.e015258.4","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejogrb.2004.07.041"},{"key":"2025121221282956000_7.10.e015258.5","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.c3428"},{"key":"2025121221282956000_7.10.e015258.6","first-page":"433","article-title":"Ethnic and racial disparities in the risk of preterm birth: a systematic review and meta-analysis","volume":"30","author":"Schaaf","year":"2013","journal-title":"Am J Perinatol"},{"key":"2025121221282956000_7.10.e015258.7","doi-asserted-by":"publisher","DOI":"10.1007\/s10995-009-0546-2"},{"key":"2025121221282956000_7.10.e015258.8","doi-asserted-by":"publisher","DOI":"10.1067\/mob.2003.339"},{"key":"2025121221282956000_7.10.e015258.9","doi-asserted-by":"crossref","first-page":"793","DOI":"10.1016\/j.midw.2010.07.006","article-title":"Advanced maternal age and adverse perinatal outcome: a review of the evidence","volume":"27","author":"Carolan","year":"2011","journal-title":"Midwifery"},{"key":"2025121221282956000_7.10.e015258.10","doi-asserted-by":"publisher","DOI":"10.1111\/j.1471-0528.1998.tb10266.x"},{"key":"2025121221282956000_7.10.e015258.11","doi-asserted-by":"publisher","DOI":"10.1016\/j.amepre.2010.05.012"},{"key":"2025121221282956000_7.10.e015258.12","doi-asserted-by":"publisher","DOI":"10.3109\/0167482X.2010.518776"},{"key":"2025121221282956000_7.10.e015258.13","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9378(00)70240-7"},{"key":"2025121221282956000_7.10.e015258.14","doi-asserted-by":"publisher","DOI":"10.3109\/00016349.2010.486827"},{"key":"2025121221282956000_7.10.e015258.15","doi-asserted-by":"publisher","DOI":"10.1016\/S1701-2163(16)35337-3"},{"key":"2025121221282956000_7.10.e015258.16","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1093\/ije\/dyq195","article-title":"Maternal underweight and the risk of preterm birth and low birth weight: a systematic review and meta-analyses","volume":"40","author":"Han","year":"2011","journal-title":"Int J Epidemiol"},{"key":"2025121221282956000_7.10.e015258.17","doi-asserted-by":"publisher","DOI":"10.3109\/14767050903042561"},{"key":"2025121221282956000_7.10.e015258.18","doi-asserted-by":"publisher","DOI":"10.1111\/ppe.12125"},{"key":"2025121221282956000_7.10.e015258.19","first-page":"1","article-title":"Births: final data for 2012","volume":"62","author":"Martin","year":"2013","journal-title":"Natl Vital Stat Rep"},{"key":"2025121221282956000_7.10.e015258.20","doi-asserted-by":"publisher","DOI":"10.1016\/j.siny.2010.06.006"},{"key":"2025121221282956000_7.10.e015258.21","doi-asserted-by":"publisher","DOI":"10.1053\/j.semperi.2012.02.001"},{"key":"2025121221282956000_7.10.e015258.22","doi-asserted-by":"crossref","first-page":"623","DOI":"10.3109\/14767058.2014.928854","article-title":"Maternal obesity in singleton versus twin gestations: a population-based matched case-control study","volume":"28","author":"Lucovnik","year":"2015","journal-title":"J Matern Fetal Neonatal Med"},{"key":"2025121221282956000_7.10.e015258.23","doi-asserted-by":"publisher","DOI":"10.1093\/aje\/kwn092"},{"key":"2025121221282956000_7.10.e015258.24","doi-asserted-by":"publisher","DOI":"10.3945\/an.111.001081"},{"key":"2025121221282956000_7.10.e015258.25","unstructured":"Rasmussen KM , Yaktine AL . Weight gain during pregnancy: reexamining the guidelines: The National Academy Press, 2009."},{"key":"2025121221282956000_7.10.e015258.26","doi-asserted-by":"publisher","DOI":"10.1111\/aogs.12685"},{"key":"2025121221282956000_7.10.e015258.27","doi-asserted-by":"crossref","first-page":"e121","DOI":"10.1016\/j.ajog.2013.04.020","article-title":"Obesity levels in a national cohort of women 9 months after delivery","volume":"209","author":"Turner","year":"2013","journal-title":"Am J Obstet Gynecol"},{"key":"2025121221282956000_7.10.e015258.28","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1097\/AOG.0b013e31827a0052","article-title":"Correlation between birth weight and maternal body composition","volume":"121","author":"Kent","year":"2013","journal-title":"Obstet Gynecol"},{"key":"2025121221282956000_7.10.e015258.29","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1055\/s-2008-1061496","article-title":"Obesity and mode of delivery in primigravid and multigravid women","volume":"25","author":"Lynch","year":"2008","journal-title":"Am J Perinatol"},{"key":"2025121221282956000_7.10.e015258.30","doi-asserted-by":"publisher","DOI":"10.3109\/00016341003801706"},{"issue":"Suppl 1","key":"2025121221282956000_7.10.e015258.31","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1111\/1471-0528.12631","article-title":"Risk factors for spontaneous and provider-initiated preterm delivery in high and low human development Index countries: a secondary analysis of the world health organization multicountry survey on maternal and newborn health","volume":"121","author":"Morisaki","year":"2014","journal-title":"BJOG"},{"key":"2025121221282956000_7.10.e015258.32","doi-asserted-by":"publisher","DOI":"10.1186\/s12884-014-0422-y"},{"key":"2025121221282956000_7.10.e015258.33","first-page":"259","article-title":"Does maternal obesity cause preeclampsia? A systematic review of the evidence","volume":"64","author":"Salihu","year":"2012","journal-title":"Minerva Ginecol"},{"key":"2025121221282956000_7.10.e015258.34","first-page":"e321","article-title":"Maternal insulin resistance and preeclampsia","volume":"204:327","author":"Hauth","year":"2011","journal-title":"Am J Obstet Gynecol"},{"key":"2025121221282956000_7.10.e015258.35","doi-asserted-by":"publisher","DOI":"10.1210\/jc.2004-0548"},{"key":"2025121221282956000_7.10.e015258.36","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.38380.674340.E0"},{"key":"2025121221282956000_7.10.e015258.37","doi-asserted-by":"publisher","DOI":"10.2105\/AJPH.2005.074294"},{"key":"2025121221282956000_7.10.e015258.38","doi-asserted-by":"publisher","DOI":"10.1007\/s00404-010-1740-6"},{"key":"2025121221282956000_7.10.e015258.39","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-3016.2007.00762.x"},{"key":"2025121221282956000_7.10.e015258.40","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2004.09.021"},{"key":"2025121221282956000_7.10.e015258.41","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2013.6295"},{"key":"2025121221282956000_7.10.e015258.42","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-3016.2012.01290.x"},{"key":"2025121221282956000_7.10.e015258.43","doi-asserted-by":"crossref","first-page":"565","DOI":"10.1016\/1047-2797(92)90001-7","article-title":"Young maternal age and parity. Influences on pregnancy outcome","volume":"2","author":"Scholl","year":"1992","journal-title":"Ann Epidemiol"},{"key":"2025121221282956000_7.10.e015258.44","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2004.10.593"},{"key":"2025121221282956000_7.10.e015258.45","doi-asserted-by":"publisher","DOI":"10.1093\/ije\/dyl284"},{"issue":"Suppl 3","key":"2025121221282956000_7.10.e015258.46","doi-asserted-by":"crossref","first-page":"S2","DOI":"10.1186\/1471-2458-13-S3-S2","article-title":"The associations of parity and maternal age with small-for-gestational-age, preterm, and neonatal and infant mortality: a meta-analysis","volume":"13","author":"Kozuki","year":"2013","journal-title":"BMC Public Health"},{"key":"2025121221282956000_7.10.e015258.47","doi-asserted-by":"publisher","DOI":"10.1001\/jama.284.3.335"},{"key":"2025121221282956000_7.10.e015258.48","doi-asserted-by":"publisher","DOI":"10.3390\/ijerph10062296"},{"key":"2025121221282956000_7.10.e015258.49","doi-asserted-by":"publisher","DOI":"10.1097\/GRF.0b013e31816f28de"},{"key":"2025121221282956000_7.10.e015258.50","doi-asserted-by":"publisher","DOI":"10.1023\/B:MACI.0000025726.53515.65"},{"key":"2025121221282956000_7.10.e015258.51","doi-asserted-by":"publisher","DOI":"10.1086\/338781"},{"key":"2025121221282956000_7.10.e015258.52","doi-asserted-by":"crossref","first-page":"52","DOI":"10.5539\/gjhs.v5n1p52","article-title":"Preterm delivery and psycho-social determinants of health based on World Health Organization model in Iran: a narrative review","volume":"5","author":"Dolatian","year":"2012","journal-title":"Glob J Health Sci"},{"key":"2025121221282956000_7.10.e015258.53","doi-asserted-by":"publisher","DOI":"10.1016\/j.puhe.2004.06.005"},{"key":"2025121221282956000_7.10.e015258.54","first-page":"728","article-title":"The Social Determinants of Health (SDH) in Iran: a systematic review article","volume":"44","author":"Bahadori","year":"2015","journal-title":"Iran J Public Health"},{"key":"2025121221282956000_7.10.e015258.55","doi-asserted-by":"publisher","DOI":"10.1136\/adc.2008.150433"},{"key":"2025121221282956000_7.10.e015258.56","doi-asserted-by":"publisher","DOI":"10.1016\/S0277-9536(03)00200-4"},{"key":"2025121221282956000_7.10.e015258.57","doi-asserted-by":"publisher","DOI":"10.1007\/s10995-008-0330-8"},{"key":"2025121221282956000_7.10.e015258.58","doi-asserted-by":"publisher","DOI":"10.1093\/eurpub\/ckr089"},{"key":"2025121221282956000_7.10.e015258.59","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2393-10-S1-S6"},{"key":"2025121221282956000_7.10.e015258.60","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2007.03.042"},{"key":"2025121221282956000_7.10.e015258.61","first-page":"53","article-title":"Conceptualization, measurement, and use of gestational age. I. Clinical and public health practice","volume":"16","author":"Alexander","year":"1996","journal-title":"J Perinatol"},{"key":"2025121221282956000_7.10.e015258.62","first-page":"267","article-title":"Gestational age reporting and preterm delivery","volume":"105","author":"Alexander","year":"1990","journal-title":"Public Health Rep"},{"key":"2025121221282956000_7.10.e015258.63","doi-asserted-by":"publisher","DOI":"10.1038\/oby.2010.25"},{"key":"2025121221282956000_7.10.e015258.64","doi-asserted-by":"publisher","DOI":"10.1097\/00001648-199003000-00011"},{"key":"2025121221282956000_7.10.e015258.65","doi-asserted-by":"publisher","DOI":"10.1007\/s10995-006-0157-0"},{"key":"2025121221282956000_7.10.e015258.66","doi-asserted-by":"crossref","first-page":"409","DOI":"10.1515\/jpm-2013-0209","article-title":"The relationship between gestational weight gain and fetal growth: time to take stock?","volume":"42","author":"O\u2019Higgins","year":"2014","journal-title":"J Perinat Med"},{"key":"2025121221282956000_7.10.e015258.67","doi-asserted-by":"crossref","first-page":"n\/a","DOI":"10.1111\/cob.12062","article-title":"A review of national health policies and professional guidelines on maternal obesity and weight gain in pregnancy","volume":"4","author":"Schumann","year":"2014","journal-title":"Clin Obes"},{"key":"2025121221282956000_7.10.e015258.68","unstructured":"World Health Organization. Obesity: preventing and managing the global epidemic: Report of a WHO consultation, 2000:0512\u20133054."},{"key":"2025121221282956000_7.10.e015258.69","doi-asserted-by":"publisher","DOI":"10.1097\/01.AOG.0000425667.10377.60"}],"container-title":["BMJ Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjopen-2016-015258","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T05:28:41Z","timestamp":1765603721000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopen.bmj.com\/lookup\/doi\/10.1136\/bmjopen-2016-015258"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,10]]},"references-count":69,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2017,10,15]]},"published-print":{"date-parts":[[2017,10]]}},"alternative-id":["10.1136\/bmjopen-2016-015258"],"URL":"https:\/\/doi.org\/10.1136\/bmjopen-2016-015258","relation":{},"ISSN":["2044-6055","2044-6055"],"issn-type":[{"value":"2044-6055","type":"print"},{"value":"2044-6055","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,10]]}}}