{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T09:31:51Z","timestamp":1740130311463,"version":"3.37.3"},"reference-count":34,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2020,1,7]],"date-time":"2020-01-07T00:00:00Z","timestamp":1578355200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Research Council of Norway","doi-asserted-by":"publisher","award":["project 262700"],"award-info":[{"award-number":["project 262700"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,4,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Our aim in this study was to analyze the importance of childbearing for risk of inflammatory bowel disease. Using data from the Norwegian Population Register and the Norwegian Patient Register, we fitted discrete-time hazard models for diagnosis of Crohn disease (CD) or ulcerative colitis (UC) among men and women aged 18\u201381 years in 2011\u20132016. Year and various sociodemographic factors were controlled for. The data included 4,304 CD cases and 8,866 UC cases. Women whose youngest child was \u22644 years of age had lower CD risk the following year than childless women (odds ratio (OR)\u00a0=\u00a00.73, 95% confidence interval (CI): 0.62, 0.86). There was no such reduction in CD risk among fathers. Men whose youngest child was aged \u226520 years had higher risks of CD (OR\u00a0=\u00a01.22, 95% CI: 1.01, 1.49) and UC (OR\u00a0=\u00a01.15, 95% CI: 1.02, 1.30) than childless men. UC risk was also increased among men whose youngest child was aged \u22644 years (OR\u00a0=\u00a01.14, 95% CI: 1.02, 1.27). The short-term reduction in women\u2019s CD risk after a birth may reflect biological effects of pregnancy. Alternatively, it may reflect residual confounding or lifestyle effects of parenthood that are of special relevance for CD in women. In particular, differences in use of oral contraceptives (which it was not possible to control for) may have contributed to the observed pattern.<\/jats:p>","DOI":"10.1093\/aje\/kwz285","type":"journal-article","created":{"date-parts":[[2019,12,19]],"date-time":"2019-12-19T20:11:34Z","timestamp":1576786294000},"page":"294-304","source":"Crossref","is-referenced-by-count":2,"title":["Association of Childbearing With a Short-Term Reduced Risk of Crohn Disease in Mothers"],"prefix":"10.1093","volume":"189","author":[{"given":"\u00d8ystein","family":"Kravdal","sequence":"first","affiliation":[{"name":"Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway"},{"name":"Department of Economics, Faculty of Social Sciences, University of Oslo, Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Per","family":"Magnus","sequence":"first","affiliation":[{"name":"Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway"},{"name":"Institute of Health and Society, University of Oslo, Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bj\u00f8rn","family":"Moum","sequence":"first","affiliation":[{"name":"Department of Gastroenterology, Oslo University Hospital, Oslo, Norway"},{"name":"Institute of Clinical Medicine, University of Oslo, Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marte Lie","family":"H\u00f8ivik","sequence":"first","affiliation":[{"name":"Department of Gastroenterology, Oslo University Hospital, Oslo, Norway"},{"name":"Institute of Clinical Medicine, University of Oslo, Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2020,1,7]]},"reference":[{"issue":"4","key":"2020060510001731200_ref1","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1038\/nrgastro.2015.34","article-title":"Epidemiology and risk factors for 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