ArticleBreast cancer research : BCR2019
Parity, breastfeeding, and breast cancer risk by hormone receptor status and molecular phenotype: results from the Nurses' Health Studies.
Article in Breast cancer research : BCR, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 78 papers, 2 of them syntheses that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
78 citing papers in PubMed, 2 syntheses or guidelines pooled it, 159 citations in OpenAlex.
- Effect of breastfeeding on the risk of breast cancer: a meta-analysis of observational studies.International breastfeeding journal · 2026Pooled it
- Association of reproductive risk factors and breast cancer molecular subtypes: a systematic review and meta-analysis.BMC cancer · 2023Pooled it
- Breast Cancer Risk Factors Analysis in Middle-Aged Women: Evidence From a Cross-Sectional Epidemiological Study.Health science reports · 2026Article
- Breastfeeding and subsequent risk of 24 types of maternal cancer: a cohort study of Chinese women.Nutrition journal · 2026Article
- Epigenome-Wide DNA Methylation Levels During Pregnancy: Associations with Parity Across Diverse Populations.Epigenomes · 2026Article
- Reproductive factors and risk of contralateral breast cancer by age and hormone receptor status: The California Breast Cancer Survivorship Consortium.International journal of cancer · 2026Article
- The association between parity, age of first full term pregnancy and invasive lobular breast cancer: a case-only analysis.Cancer treatment and research communications · 2026Article
- Modifiable and Nonmodifiable Risk Factors for Breast Cancer: A Comprehensive Scoping Review.International journal of breast cancer · 2026Review
- The aetiology of breast cancer subtypes: results from the Million Women Study.Breast cancer research : BCR · 2025Article
- Impact of obesity on breast cancer recurrence by menopausal status and subtype: a retrospective cohort study.Breast cancer research and treatment · 2025Article
- Impact of timing and breastfeeding on postpartum breast cancer diagnostic patterns and outcomes.Breast cancer research and treatment · 2025Article
- Subtype-specific expression of lncRNAs SNHG12 and HAGLR as non-invasive biomarkers for diagnosis and prognosis in breast cancer.Irish journal of medical science · 2025Article
- Understanding Trends in Incidence and Management of Pregnancy-Associated Breast Cancer in a National Sample Using Claims Data.Journal of surgical oncology · 2025Article
- Parity, breastfeeding, and the risk of early-onset breast cancer in women with a BRCA1 pathogenic variant.British journal of cancer · 2025Article
- Chemical exposomics in biobanked plasma samples and associations with breast cancer risk factors.Journal of exposure science & environmental epidemiology · 2025Article
- Curvilinear incidence models for parity in the entire fertility range for cancers of the breast, ovary, and endometrium: A follow-up of the Norwegian 1960 Census.International journal of cancer · 2025Article
- Risk Factors Associated with Breast Cancer among Women in Iraq: A Case-Control Study.Asian Pacific journal of cancer prevention : APJCP · 2025Article
- Associations of DNA methylation in breast tumour subtypes with parity and breastfeeding in a cohort of 1459 Black women: implications for public health.BMJ oncology · 2025Article
- Breast cancer shares many epidemiological, lifestyle, and local hormonal and metabolic underpinnings with endometrial and ovarian cancer: a narrative review.Translational breast cancer research : a journal focusing on translational research in breast cancer · 2025Review
- Single-Cell Analysis in the Mouse and Human Mammary Gland.Advances in experimental medicine and biology · 2025Review
18 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
8 authors at 3 institutions in 2 countries.
Funding
Abstract
backgroundEpidemiologic data suggest that parity increases risk of hormone receptor-negative breast cancer and that breastfeeding attenuates this association. Prospective data, particularly on the joint effects of higher parity and breastfeeding, are limited.
methodsWe investigated parity, breastfeeding, and breast cancer risk by hormone-receptor (estrogen (ER) and progesterone receptor (PR)) and molecular subtypes (luminal A, luminal B, HER2-enriched, and basal-like) in the Nurses' Health Study (NHS; 1976-2012) and NHSII (1989-2013). A total of 12,452 (ER+ n = 8235; ER- n = 1978) breast cancers were diagnosed among 199,514 women. We used Cox proportional hazards models, adjusted for breast cancer risk factors, to calculate hazard ratios (HR) and 95% confidence intervals (CI).
resultsParous women had lower risk of ER+ breast cancer (vs. nulliparous, HR = 0.82 [0.77-0.88]); no association was observed for ER- disease (0.98 [0.84-1.13]; P
conclusionsThis study provides evidence that breastfeeding is inversely associated with hormone receptor-negative breast cancers, representing an accessible and cost-effective risk-reduction strategy for aggressive disease subtypes.
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