Birth weight and subsequent risk of cancer

Cancer Epidemiol. 2014 Oct;38(5):538-43. doi: 10.1016/j.canep.2014.07.004. Epub 2014 Aug 3.


Background: We aimed to determine the association between self-reported birth weight and incident cancer in the Women's Health Initiative Observational Study cohort, a large multiethnic cohort of postmenopausal women.

Methods: 65,850 women reported their birth weight by category (<6 lbs, 6-7 lbs 15 oz, 8-9 lbs 15 oz, and ≥10 lbs). All self-reported, incident cancers were adjudicated by study staff. We used Cox proportional hazards regression to estimate crude and adjusted hazard ratios (aHR) for associations between birth weight and: (1) all cancer sites combined, (2) gynecologic cancers, and (3) several site-specific cancer sites.

Results: After adjustments, birth weight was positively associated with the risk of lung cancer (p=0.01), and colon cancer (p=0.04). An inverse trend was observed between birth weight and risk for leukemia (p=0.04). A significant trend was not observed with breast cancer risk (p=0.67); however, women born weighing ≥10 lbs were less likely to develop breast cancer compared to women born between 6 lbs-7 lbs 15 oz (aHR 0.77, 95% CI 0.63, 0.94).

Conclusion: Birth weight category appears to be significantly associated with the risk of any postmenopausal incident cancer, though the direction of the association varies by cancer type.

Keywords: Birth weight; Breast neoplasms; Colorectal neoplasms; Endometrial neoplasms; Leukemia; Lung neoplasms; Neoplasms; Ovarian neoplasms.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Birth Weight / physiology*
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Middle Aged
  • Neoplasms / epidemiology*
  • Neoplasms / pathology
  • Postmenopause*
  • Proportional Hazards Models
  • Prospective Studies
  • Risk