How breastfeeding affects breast cancer risk
Official title: Lactation on Breast Tumorigenesis
Funded at Baylor College of Medicine · NIH-11321084 · Data updated 2026-11-12
This project looks at whether breastfeeding changes breast cancer risk, especially for women who delay their first birth or who have atypical breast cells.
Quick facts
| Grant type | R01 grant |
|---|---|
| Study type | NIH-funded research |
| Funding institution | Baylor College of Medicine NIH-funded |
| Lab location | 1 site (Houston, United States) |
| Project start | May 1, 2023 |
| Project end | April 30, 2028 |
| Funding year | 2026 |
| Award (this year) | $523,286 |
| NIH project number | 5R01CA271588-04 |
| Project ID | NIH-11321084 on NIH RePORTER |
Who could benefit from this research
✓Could help
Ideal candidates would include women who are pregnant or planning pregnancy, particularly first-time mothers aged 35 or older and women diagnosed with breast atypia.
✕Less likely to help
Women without a history of breast atypia or not planning pregnancy are less likely to get direct benefit from this specific research.
What this research studies
You would learn whether it is pregnancy itself or the breastfeeding that follows which influences breast cancer risk, by combining population data with laboratory experiments. Researchers will compare outcomes for women who gave birth at different ages and for tissues with early abnormal cells (atypia). In the lab they will study how lactation affects preexisting lesions and the molecular signals involved. Results aim to give clearer, evidence-based information for women facing decisions about breastfeeding after a late first pregnancy or an atypia diagnosis.
Why it matters
Potential benefit: If confirmed, the findings could help women—especially those with atypia or late first childbirth—make informed choices about breastfeeding and timing of pregnancy.
How similar studies have gone: Large epidemiologic studies show early pregnancy and breastfeeding generally lower breast cancer risk, but the specific idea that lactation may trigger progression of preexisting atypia is largely novel and not yet established experimentally in humans.
Where this research is happening
-
Baylor College of Medicine
Houston, United States Active
Researchers
- Principal investigator: Li, Yi — Baylor College of Medicine
- Study coordinator: Li, Yi
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About this research
- This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
- Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
- For full project details, budget, and progress reports, visit the official NIH RePORTER page.