Mastitis is painful swelling and redness in the breast. It is especially common among women who are breastfeeding. While it is most common in just one breast it can occur in both.

Mastitis
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Mastitis is often caused by trapped breast milk in a milk duct. The trapped breast milk can irritate the tissue around it and cause swelling and pain.

Mastitis can also be caused by a bacterial infection in the breast tissue. Milk ducts or cracked skin around the nipple can allow bacteria to enter the breast and cause an infection.

Mastitis often occurs during breastfeeding but, it is possible to get mastitis at other times. This article will focus on symptoms and treatment of lactation-associated mastitis.