Breastfeeding with mastitis

How do I breastfeed with mastitis?

Mothers with mastitis should continue to breastfeed if possible. It’s nearly always better for the mother and the baby. Breastfeeding is the most effective way to remove milk from the breast, and poor emptying can make mastitis worse or result in a breast abscess. To breastfeed with mastitis, mothers need to ensure the mastitis is being treated properly and should feed according to the baby’s hunger signs. If the baby is reluctant to feed on the infected breast, mothers should try to start all feeds on that side and massage the nipple root if it is swollen. If mothers cannot breastfeed, they need to express for every feed that the baby misses. They can also consider pain medication and cold compresses. The baby's growth should be monitored during this time.

A) Reasons to continue breastfeeding with mastitis

Mothers who have mastitis should see their health-care providers for help with diagnosis and treatment.

1) Benefits for mothers

As part of mastitis treatment, mothers should empty their breasts well and regularly to speed the healing of mastitis. Poor breast emptying can result in:

  • The mastitis getting worse.
  • The mastitis taking longer to clear.
  • An increased risk of developing an abscess.
  • An increased risk of reducing the milk supply.

There is clear evidence that mothers should continue breastfeeding if they have mastitis as this is the best way to empty the breast (Amir 2014; WHO 2000). 

Mothers should only express if necessary. The pain and swelling caused by mastitis sometimes interferes with the let-down and the passage of milk out of the breast and results in poor emptying. This can happen while breastfeeding but is even more likely when expressing. Unfortunately, some mothers choose to express because they worry needlessly that they will harm the baby by continuing to breastfeed.

In general, mothers should not wean or attempt to dry-up their breasts when they have mastitis.

2) Benefits for babies

When a mother has mastitis, it is nearly always safer for the baby to continue breastfeeding. Breast milk offers protection from infection.

It is possible but very unlikely that dangerous bacteria from the breast will suddenly be transmitted to the baby once the mother develops mastitis (Ueda 2018). Rather mothers and babies share bacteria from birth, including S. aureus, the bacteria that most commonly causes mastitis (Benito 2015). Premature babies may be at an increased risk of infection as their immune systems are weaker (Ager 2020) but this remains rare.

B) How to breastfeed with mastitis

Breastfeed the baby according to the baby’s hunger signs, offering both breasts at each feed. 

It is best to keep the milk supply balanced between the breasts and avoid excess breastfeeding on one side. This can happen when mothers increase breastfeeding or expressing on the breast with the mastitis to speed healing or avoid it because of pain.

After feeds, the areas of the breast away from the mastitis should be empty and soft. There are several tools available if not and should be used gently. The area of the mastitis may feel full after feeds because of inflammation. This will settle with appropriate antibiotic treatment.  

C) The effect of mastitis on milk supply

Severe mastitis can decrease the milk supply temporarily on the affected side. Most mothers have a normal supply after the mastitis has cleared, but a few have a permanently reduced supply.

Mothers may notice the baby is reluctant to or refuses to breastfeed on the affected side. The baby may grow slowly if the normal breast cannot compensate by making extra milk.

Mothers with mastitis need to make sure the baby is getting enough milk. If not, they may have to supplement the baby with milk temporarily or permanently.

D) Breast reluctance or refusal

Some mothers with mastitis say their babies are less happy to feed on the affected breast or may refuse the breast altogether. There are a number of reasons for this.

1) Reasons for breast reluctance

1) Less milk available

Pain can interfere with the let-down, resulting in less milk being available to the baby. Swelling from the infection may also block ducts and limit milk flow. Milk supply usually returns to normal after the mastitis has cleared unless it is particularly severe.

2) Changes in the nipple root

Firmness of the nipple root caused by swelling can make it harder for the baby to latch. Nipple root massage may help to soften the area.

3) The taste of the milk

The milk may taste different. It is thought that the milk-making cells of the breast are not connected as tightly when mastitis is present, allowing sodium to pass from the blood, between the cells, and into the milk making the milk taste saltier (Owens 2013).

Milk from a breast that has mastitis has been reported to have less fat, carbohydrate, and energy (Prentice 1985; Say 2016).

The taste and composition return to normal once the mastitis has cleared.

4) The baby is responding to the mother’s pain

Mothers with mastitis may have a lot of pain and their babies can sense that something is different when breastfeeding on the affected side. Babies may notice the following changes:

  • The mother is holding the baby more tightly.
  • The mother’s body is tense during the feeding.
  • The mother’s breathing and heart rate have increased.
  • The mother has changed her breastfeeding hold or position.

Mother may need additional ways to manage their pain.

2) Treating breast reluctance and refusal

If the baby is less happy to breastfeed on the breast with mastitis:

  • Instead of changing the starting side, start all feeds on the affected side.
  • Use the pinch test to ensure that the nipple root is not swollen.
  • Treat any nipple root swelling with massage.
  • If the baby still feeds poorly on the affected side, consider:

Most babies return to normal breastfeeding as the infection clears.

E) Dealing with pain

Most mothers continue to breastfeed with mastitis if it is treated quickly and appropriately. Pain can be managed with: 

If you cannot breastfeed on the affected breast because of pain, consider the following, in order of preference:

  1. Continue breastfeeding on the unaffected breast.
  2. Expressing the one with mastitis occasionally until you can resume breastfeeding.
  3. Expressing instead of breastfeeding until you can resume breastfeeding.
  4. Optimizing breast emptying.

F) Expressing with mastitis

Expressing may not be as effective as breastfeeding. If mothers need to or choose to express, they can continue to breastfeed on the unaffected side. They should:

  • Consider alternating breastfeeding and expressing instead of just expressing on the affected side. 
  • Minimize the number of expressions and resume breastfeeding as soon as possible. 
  • Express for every feed that the baby misses.
  • Ensure it is effective and if not, they should consider tools to fix this.


Ager EPC, Steele ED, Nielsen LE, et al. Hypervirulent Streptococcus agalactiae septicemia in twin ex-premature infants transmitted by breast milk: report of source detection and isolate characterization using commonly available molecular diagnostic methods. Ann Clin Microbiol Antimicrob. 2020 Nov 26;19(1):55

Amir LH; Academy of Breastfeeding Medicine Protocol Committee. ABM clinical protocol #4: Mastitis, revised March 2014. Breastfeed Med. 2014 Jun;9(5):239-43
Benito D, Lozano C, Jiménez E, et al. Characterization of Staphylococcus aureus strains isolated from faeces of healthy neonates and potential mother-to-infant microbial transmission through breastfeeding. FEMS Microbiol Ecol. 2015 Mar;91(3)
Owens MB, Hill AD, Hopkins AM. Ductal barriers in mammary epithelium. Tissue Barriers. 2013 Oct 1;1(4):e25933
Prentice A, Prentice AM, Lamb WH. Mastitis in rural Gambian mothers and the protection of the breast by milk antimicrobial factors. Trans R Soc Trop Med Hyg. 1985;79(1):90-5
Say B, Dizdar EA, Degirmencioglu H, et al. The effect of lactational mastitis on the macronutrient content of breast milk. Early Hum Dev. 2016 Jul;98:7-9
Ueda NK, Nakamura K, Go H, et al. Neonatal meningitis and recurrent bacteremia with group B Streptococcus transmitted by own mother's milk: A case report and review of previous cases. Int J Infect Dis. 2018 Jun 26;74:13-15
World Health Organization (WHO). Mastitis: Causes and Management. Publication number WHO/FCH/CAH/00.13. World Health Organization: Geneva; 2000