Breastfeeding protects against breast cancer, especially in premenopausal women [171-173]. Breastfeeding appears to lower the risk of both estrogen receptor-positive and estrogen receptor-negative tumors [173]. In a pooled analysis of 47 studies, mothers who breastfed for a lifetime total of one year (combined duration of breastfeeding for all children) were slightly less likely to get breast cancer than those who never breastfed [172]. Mothers who breastfed for a lifetime total of two years got about twice the benefit of those who breastfed for a total of one year [172]. Women who breastfed for a lifetime total of more than two years had even more benefit. Although data are limited, breastfeeding for less than one year may also modestly lower breast cancer risk.
Breastfeeding has other benefits such as fewer childhood infections for the breastfed child, fewer sick days used to care for an ill child, a quicker return to pre-pregnancy weight and possibly a lower risk of ovarian cancer. Combined with a reduced risk of breast cancer, there are compelling reasons for women to choose to breastfeed their children if they are able to do so [174].
Updated 11/10/09
