- Breastfeeding was associated with a 30% reduction in risk for epithelial ovarian cancer (EOC); the association persisted for more than 30 years.
- Breastfeeding for 3 months was associated with statistically significant reduction in risk.
- Longer breastfeeding duration and greater number of breastfeeding episodes were associated with increased protection.
Why this matters
- Measures to encourage and support women in breastfeeding may help reduce EOC risk.
- Study included 689 incident EOC cases and 1572 healthy women.
- Funding: National Cancer Institute
- Women who breastfed any offspring showed significant reduction in risk for EOC (OR, 0.70; 95% CI, 0.58-0.85) vs those who never breastfed.
- More recent breastfeeding was associated with 44% reduction in risk (OR, 0.56; [95% CI, 0.32-0.95] for time since last breastfeeding within the last 10 years).
- Association decreased but remained significant for >30 years since last episode (OR, 0.69; 95% CI, 0.53-0.88),
- Average 3 months breastfeeding episode was associated with reduced risk (OR, 0.73; 95% CI, 0.58-0.80).
- Longer breastfeeding duration was also associated with reduced risk (compared with never being breastfed, ORs for 1 year: 0.75 [95% CI, 0.61-0.94] and 0.62 [95% CI, 0.47-0.80]).
- A greater number of breastfeeding episodes was associated with greater risk reduction (Ptrend=.01).
- Recall bias.