我查到的數據說:Breastfeeding may slightly decrease the risk for breast cancer, especially if over 1.5-2 years.
(http://www.cancer.org)
另外一篇文章說,Breast feeding lowers breast cancer risk by 4.3% for every year of feeding.There is also a 7% reduction in risk of breast cancer for each child born.
(http://www.cancerresearchuk.org)