Oftentimes, bleeding nipples aren't cause for concern. They're usually the result of some sort of trauma or friction, like your nipple rubbing against a scratchy bra or shirt material. Bloody or otherwise, abnormal nipple discharge is relatively common, regardless of whether you're breastfeeding. read more
One cannot tell why without more information. However, some answers to this can be serious that is why I'm attempting to tell you generally why there is blood coming from your breast. read more
Blood that appears from the nipples can be due to bleeding from the skin of the nipples or from inside the breast. The skin of the nipples can often be affected by eczema, which can cause sore, itchy flaking skin which bleeds particularly when it is rubbed by a close fitting bra. read more
The most common causes of bleeding or discharge from nipple are fibroadenoma, galactorrhea of unknown cause, and breast infection (mastitis). read more