By Barbara Wilson Clay, BSEd, IBCLC

Mastitis, or inflammation of the breast, is a relatively common problem for breastfeeding mothers. An area of the nipple or breast becomes painful, red, hard, and may be followed by fever and flu-like symptoms. Experts cannot agree on whether all cases of mastitis represent a true infection. Sometimes, mastitis may be caused by the breast becoming over-full, or blocked because of milk over-supply, ineffective breastfeeding, missed feeds, restrictive clothing, or bruising. The pooled milk that is trapped in the breast can trigger chemical changes that cause pain and redness. This inflammation responds well to extra rest for the mother, and thorough emptying of the affected breast. Some experts suggest using heat and others suggest cold compresses during mastitis. Use of heat should be brief, perhaps just before pumping or breastfeeding in order to prevent more inflammation. Cold may help reduce swelling.

Mastitis is most common in the first few weeks postpartum, although it can happen at any time, especially if a mother is over-tired, or if she smokes. Cracked nipples put a woman more at risk for infective mastitis. When the skin is broken, germs from the hospital environment, from the mother’s skin, or from the baby’s mouth may penetrate the breast. A woman should call the doctor if she experiences intense pain or fever. (Occasionally women who already are taking ibuprofen or Tylenol don’t realize they have a fever.) Some experts advise rest, hot or cold compresses, and breast emptying for 12 hours. Then, if the symptoms don’t resolve, antibiotics are prescribed. Others begin antibiotic at the first sign of mastitis. Your doctor can guide you, and he or she will chose medications that are considered compatible with breastfeeding. If you begin antibiotic therapy, it is very important to complete your full prescription in order to prevent recurrences. Please note that some mothers who are on antibiotics may develop yeast infections, and will need to be treated for this.

The most important thing to do if you get mastitis is to continue to breastfeed. Emptying the breast is the best way to obtain relief and help the healing process. Abrupt weaning may cause complications such as breast abscesses. Consider speaking to a breastfeeding support person, such as an IBCLC if you develop mastitis in order to find out about simple ways to prevent it in the future.

In rare cases, mastitis may result from a more serious type of underlying breast problem. Because women often are treated over the phone for this condition, it is important to see the doctor if you have repeated episodes of mastitis that are always located in the same area of the breast, or if lumps, pain, and redness don’t resolve after treatment. Ultrasound is a safe and effective method to identify abscesses or tumors in the lactating breast. Breastfeeding can continue during treatment for abscesses.

Kathleen B. Bruce, BSN, IBCLC
Catherine Watson Genna, BS, IBCLC
Mary Bibb BA, IBCLC


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