{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T19:58:58Z","timestamp":1787169538484,"version":"build-2736575974"},"reference-count":36,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2022,6,1]],"date-time":"2022-06-01T00:00:00Z","timestamp":1654041600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research Council"},{"name":"German Federal Ministry of Education and Research","award":["01KH0404"],"award-info":[{"award-number":["01KH0404"]}]},{"name":"German Federal Ministry of Education and Research","award":["01ER0814"],"award-info":[{"award-number":["01ER0814"]}]},{"name":"German Federal Ministry of Education and Research","award":["01ER0815"],"award-info":[{"award-number":["01ER0815"]}]},{"name":"German Federal Ministry of Education and Research","award":["01ER1505A"],"award-info":[{"award-number":["01ER1505A"]}]},{"name":"German Federal Ministry of Education and Research","award":["01ER1505B"],"award-info":[{"award-number":["01ER1505B"]}]},{"name":"Interdisciplinary Research Program of the National Center for Tumor Diseases"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Hormone-replacement therapy (HRT) is associated with lower colorectal cancer (CRC) risk among postmenopausal women. However, little is known about the effects of lifetime exposure of women to varying levels of estrogen and progesterone through reproductive factors such as parity, use of oral contraceptives (OC), breastfeeding, and menstruation on CRC risk.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We assessed associations between reproductive factors and CRC risk among 2650 female CRC patients aged 30+ years and 2175 matched controls in a population-based study in Germany, adjusting for potential confounders by multiple logistic regression.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Inverse associations with CRC risk were found for numbers of pregnancies (odds ratio [OR] per pregnancy\u2009=\u20090.91, 95% confidence interval [CI] = 0.86 to 0.97), breastfeeding for 12\u2009months and longer (OR\u2009=\u20090.74, 95% CI = 0.61 to 0.90), and use of either OC or HRT (OR\u2009=\u20090.75, 95% CI = 0.64 to 0.87) or both (OR\u2009=\u20090.58, 95% CI = 0.48 to 0.70). Similar results were found for postmenopausal women only and when adjusting for number of pregnancies and for all reproductive factors analyzed together. Breastfeeding duration of 12\u2009months and longer was associated with lower risk of cancer only in the proximal colon (OR\u2009=\u20090.58, 95% CI = 0.45 to 0.74).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Several reproductive factors were associated with lower CRC risk in women, including number of pregnancies, breastfeeding duration, and use of OC and HRT. This suggests that women\u2019s exposure to female reproductive hormones plays a key role in the difference in CRC risk between women and men and in site-specific CRC risk.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jncics\/pkac042","type":"journal-article","created":{"date-parts":[[2022,6,1]],"date-time":"2022-06-01T08:43:36Z","timestamp":1654073016000},"source":"Crossref","is-referenced-by-count":9,"title":["Reproductive Factors and Colorectal Cancer Risk: A Population-Based Case-Control Study"],"prefix":"10.1093","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8585-7622","authenticated-orcid":false,"given":"Efrat L","family":"Amitay","sequence":"first","affiliation":[{"name":"Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ) , Heidelberg, 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