Mastitis and breast abscesses

How common are they?

Mastitis or inflammation of the breast is a common condition in women who are breastfeeding or lactating. The incidence has been reported as 20% in the first 6 months after birth.

A study in Scotland in 2007 found that out of a cohort of 420 breastfeeding women 74 (17.6%) experienced at least 1 episode of mastitis. The majority of these mastitis sufferers experienced the first episode within the first 6 weeks post-birth and 10% of women received inappropriate advice and were advised to stop breastfeeding from the affected breast or to discontinue breastfeeding totally.

Breast abscesses have been reported to occur in 11% of women. Amir & Lumley (2006) have discussed the importance of general practitioners providing emotional support for breastfeeding women with mastitis and how the GP has an important role to play in supporting breastfeeding continuance.

Clinical definition of infective mastitis

  • Tender hot swollen wedge shaped area of breast
  • Temperature of 38.5°C or over
  • Chills
  • Headache
  • Flu-like symptoms
  • Systemic illness

Predisposing factors

  • Nipple damage
  • History of problems with latching the baby on the breast
  • Stress and exhaustion
  • Missed feedings and milk stasis
  • Previous mastitis history with other babies (identified by Foxman et al)
  • Use of a manual breast pump (identified by Foxman et al)

The Academy of Breastfeeding Medicine (Protocol 4) note that the World Health Organization recommend breast-milk-culture and sensitivity testing if there is no response to antibiotics within 2 days, if the mastitis recurs, if it is a hospital-acquired mastitis or in severe and unusual cases.

Treatment and management

Mastitis as a term signifies any inflammation of the breast and this may not involve a bacterial infection.

Redness, discomfort and a blocked area of the breast may be present in the absence of infection.

In the absence of systemic signs, conservative treatment involves continuing breastfeeding, making sure breast milk is removed from the breast frequently and regularly, which may involve breast expression if the baby is not feeding well, resting and application of heat to the affected area.

Effective treatment and support for breastfeeding continuance are essential. Failure to remove milk from the affected breast may predispose the breastfeeding woman to a lactation abscess.


  • Examine any breastfeeding mothers who complain of breast pain.
  • Encourage effective and frequent milk removal.
  • Advise to begin feeding on the unaffected breast if pain is inhibiting let-down of milk.
  • Advise to switch to the affected breast after milk let-down.
  • Advise gentle breast massage of the affected area during expression or breastfeeding.
  • Advise continuation of breastfeeding.
  • Advise rest.
  • Advise to apply heat to the affected area before a feed.


An anti-inflammatory such as ibuprofen is safe for breastfeeding.


If symptoms of mastitis have not improved within 24 hours or if the woman is feeling ill, antibiotic treatment should be started.

Staphalococcus Aureus and coagulase-negative staphylococci are the most common pathogens and flucloxacillin 500 mg QID is usually given.

Treatment duration of 10–14 days is recommended by clinical practitioners although there have been no clinical trials.

Short courses of antibiotics have been associated with a high incidence of relapse.

If the woman is allergic to penicillin, cephalexin or clindamycin may be indicated.

Oral antibiotics may not be appropriate in severe cases of mastitis and a woman may need to be admitted for IV-antibiotic treatment.

Breast abscess

If all the appropriate treatment for mastitis has been given and an area of the breastfeeding mother’s breast remains hard, reddened and painful an abscess may have formed or be forming.

In some situations the woman may be feeling well again due to the antibiotic treatment and breast drainage and pyrexia may have resolved.

Diagnosis and treatment

A breast ultrasound may identify the abscess area.

Appropriate initial treatment is likely to be needle aspiration which may require repeating.

If there are multiple abscesses or if the abscess is large or unresponsive to repeated aspiration treatments surgical drainage is necessary.

The breast will still require milk drainage and in many cases breastfeeding continues after the surgical drainage when the mother is on further antibiotic treatment.

In some severe cases a mother with repeated serious breast abscesses requiring drainage may decide to allow the affected breast to involute and continue one breast feeding.

Guidance is required to reduce lactation safely without causing further pathology. A referral to a lactation consultant is advised.

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