Mastitis is an infection of the breast tissue that causes breast pain, swelling, warmth, and redness of the breast. Mastitis affects about 10% of women who are breastfeeding (lactation mastitis). It is usually caused by a blocked milk duct, which causes bacteria to multiply. The bacteria normally live on the skin or in the mouth of a nursing infant and are transferred to the breast during nursing.

Mastitis sometimes can occur in women who aren't breastfeeding.

Symptoms

Breast pain
Swelling
Warm to the touch
Redness of the breast
May cause cracked nipples
Fever
Fatigue

Treatment

You should see a doctor to confirm your diagnosis and get treated, as mastitis can cause women to stop breastfeeding because of the pain. Also, bacterial infections will need to be treated with antibiotics.

Treatment includes changing breastfeeding techniques. Your doctor may recommend that you see a lactation consultant.

You can reduce your risk of mastitis with complete emptying of the breast when breastfeeding or pumping, and by improving your breastfeeding technique.

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Jeffrey M. Rothschild, MD, MPH.

Associate Professor of Medicine, Brigham and Women’s Hospital

Dr. Rothschild has been a faculty member at Brigham and Women’s Hospital where he is an Associate Professor of Medicine at Harvard Medical School. He currently practices as a hospitalist at Newton Wellesley Hospital. In 1978, Dr. Rothschild received his MD at the Medical College of Wisconsin and trained in internal medicine followed by a fellowship in critical care medicine. He also received an MP...

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