Topic Overview

What is mastitis?

Mastitis is a breast inflammation usually caused by infection. It can happen to any woman, although mastitis is most common during the first 6 months of breast-feeding. It can leave a new mother feeling very tired and run-down. Add the illness to the demands of taking care of a newborn, and many women quit breast-feeding altogether. But you can continue to nurse your baby. In fact, breast-feeding usually helps to clear up infection, and nursing will not harm your baby.

Although mastitis can be discouraging and painful, it is usually easily cleared up with medicine.

What causes mastitis?

Mastitis most often happens when bacteria enter the breast through the nipple. This can happen when a nursing mother has a cracked or sore nipple.

Going for long stretches between nursing or failing to empty the breast completely may also contribute to mastitis. Using different breast-feeding techniques and making sure your baby is latched on properly when nursing will help with emptying the breast and avoiding cracked nipples. View a slideshow on latching to learn how to get your baby to latch on.

What are the symptoms?

Mastitis usually starts as a painful area in one breast. It may be red or warm to the touch, or both. You may also have fever, chills, and body aches.

Signs that mastitis is getting worse include swollen, painful lymph nodes in the armpit next to the infected breast, a fast heart rate, and flu-like symptoms that get worse. Mastitis can lead to a breast abscess, which feels like a hard, painful lump.

What increases your risk of getting mastitis?

You are more likely to get mastitis while breast-feeding if:

• You have had mastitis before.¹
• You delay or skip breast-feeding or pumping sessions. When you don't empty the breast regularly or completely, your breasts become engorged or too full, which can lead to mastitis.
• You have cracked or irritated nipples, which can be caused by poor positioning or poor latching on.
• You have anemia. Anemia makes you tire more easily and lowers your resistance to infections like mastitis.

Breast-feeding mothers can get mastitis at any time, but especially during the baby’s first 2 months. After 2 months, the baby’s feeding patterns become more regular, which helps prevent mastitis.

How is mastitis diagnosed?

Your doctor can tell whether you have mastitis by talking with you about your symptoms and examining you. Testing is usually not needed.