biostudies-literatureVohra SNKomen Graduate Training in Disparities Research GrantUNC Cancer Control Education ProgramNCI NIH HHSUniversity Cancer Research Fund of North Carolina, the Komen Graduate Training in Disparities ResearchNIHNCI NIHUniversity Cancer Research Fund of North Carolina and Susan G. Komen for the Cure561-568https://www.ebi.ac.uk/biostudies/studies/S-EPMC8901538biostudies-literatureUnknown31(3)<h4>Background</h4>Breast cancers in recently postpartum women may have worse outcomes, but studies examining tumor molecular features by pregnancy recency have shown conflicting results.<h4>Methods</h4>This analysis used Carolina Breast Cancer Study data to examine clinical and molecular tumor features among women less than 50 years of age who were recently (≤10 years prior) or remotely (>10 years prior) postpartum, or nulliparous. Prevalence odds ratios (POR) and 95% confidence intervals (CI) were estimated using multivariable models.<h4>Results</h4>Recently postpartum women (N = 618) were more frequently lymph node-positive [POR (95% CI): 1.66 (1.26-2.19)], estrogen receptor (ER)-negative [1.37 (1.02-1.83)], and IHC-based triple negative [1.57 (1.00-2.47)] compared with nulliparous (N =Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive OncologyMolecular and Clinical Characterization of Postpartum-Associated Breast Cancer in the Carolina Breast Cancer Study Phase I-III, 1993-2013.PMC8901538T32CA057726OGUNC1202P30CA016086P50 CA058223T32 CA057726P30 CA016086GTDR16381071P50-CA58223P01 CA151135P01CA151135Sherman MESchedin PHamilton AMTroester MAWalens ALove MINichols HBOlshan AFVohra SNReeder-Hayes KEfalseMolecular and Clinical Characterization of Postpartum-Associated Breast Cancer in the Carolina Breast Cancer Study Phase I-III, 1993-2013.<h4>Background</h4>Breast cancers in recently postpartum women may have worse outcomes, but studies examining tumor molecular features by pregnancy recency have shown conflicting results.<h4>Methods</h4>This analysis used Carolina Breast Cancer Study data to examine clinical and molecular tumor features among women less than 50 years of age who were recently (≤10 years prior) or remotely (>10 years prior) postpartum, or nulliparous. Prevalence odds ratios (POR) and 95% confidence intervals (CI) were estimated using multivariable models.<h4>Results</h4>Recently postpartum women (N = 618) were more frequently lymph node-positive [POR (95% CI): 1.66 (1.26-2.19)], estrogen receptor (ER)-negative [1.37 (1.02-1.83)], and IHC-based triple negative [1.57 (1.00-2.47)] compared with nulliparous (N =2022-01-01T00:00:00Z2022 Mar2025-04-22T09:59:53.082Z2025-04-05T23:24:15.148ZS-EPMC89015383481021110.1158/1055-9965.epi-21-094010.1158/1055-9965.EPI-21-0940