What is mastitis?
Mastitis is inflammation of the breast, usually caused by a blocked milk duct. When breast milk banks up behind the blocked duct, it cannot flow out of the nipple and instead is forced into the surrounding breast tissues. This causes the breast to become inflamed. Sometimes infection also occurs.
What causes mastitis?
Some women are more prone to mastitis than others. There are a range of common causes for mastitis including:
- poor attachment to the breast
- nipple damage
- a long break between breastfeeds
- breasts that are too full — ‘engorged’
- blocked milk ducts
- stopping breastfeeding too quickly
- wearing an overly tight bra or tight clothing
- a baby with tongue tie who is having problems attaching to the breast
- holding the breast too tightly during breastfeeds
- trauma to the breast from a kicking toddler or seat belt
What are the symptoms of mastitis?
Early symptoms of mastitis can be similar to getting the ‘flu’. Shivers, shakes, aching bones and generally feeling unwell are common experiences. You may feel a sore spot in your breast, similar to a blocked duct, but worse. Part of the breast may appear red, shiny and swollen. Your breast may also feel hot to touch and painful. Mastitis symptoms can happen very quickly.
Is mastitis infectious?
Mastitis can be caused by either blocked milk ducts — non-infective mastitis, or a bacterial infection — infective mastitis. When there is a breakdown in the protective barrier of the skin, like from a cracked nipple, bacteria can enter the breast and cause an infection.
How is mastitis treated?
Antibiotics help to clear the infection and prevent further complications. See your doctor as soon as possible if you think you may have mastitis.
Warmth and cold
A combination of warmth and cold can help to soothe and relieve symptoms of mastitis. Cold packs can help to relieve inflammation. Warmth can be applied just before feeding though only for a few minutes. Warmth can also help to trigger the ‘let-down’ reflex which will help to clear the blockage and relieve pain.
Use warmth from a warm shower or use a heat pack, a covered hot water bottle, warm hand towel or face washer wrung out in hot water.
Other ways you can help treat mastitis include the following:
- Make sure your baby is feeding well on the affected breast — offering the affected breast first can help.
- Change your baby’s feeding position during breastfeeds.
- Aim for frequent drainage of the breast using breast compression when breastfeeding and expressing your breasts.
- If the blockage doesn’t clear within 8 to 12 hours or you start to feel unwell, see your doctor.
- Take paracetamol in the recommended dose — speak with your doctor or a pharmacist if you’re unsure.
- Rest and sleep when you can — recovery from mastitis is usually quick though relies on frequent feeding, the correct antibiotic treatment and self-care.
If you suspect you have mastitis, see your doctor as soon as possible. It can be difficult to distinguish between simple inflammation and a bacterial infection in the early stages.
Can I breastfeed if I have mastitis?
It’s important to keep breastfeeding if you have mastitis. Feeding your baby more frequently will help to keep your breasts as empty as possible and drain the milk from your breast.
When breastfeeding, make sure to:
- offer the affected side first and encourage your baby to suck effectively
- offer the other breast as well, this will help to avoid engorgement and potential mastitis in the other breast
- ensure your baby is well positioned and attached to your breast when they feed
- loosen your bra or take it off for feeds
- aim to relax during feeding, this will help you to ‘let down’ and for the milk to flow
- gently massage your breast by stroking towards the nipple
- if your baby does not feed well, gently express your breast milk
Can I prevent mastitis?
There are a few things which can be useful to prevent mastitis:
- Breastfeed as often as your baby needs — frequent breastfeeding helps to drain the breasts.
- Avoid missing feeds.
- Wake your baby to breastfeed if your breasts feel engorged or uncomfortably full.
- Offer both breasts when you feed — if you’re only feeding on one side, offer the alternate side the next time you feed.
- Express a small amount of milk after feeds if your breasts are still full — express for comfort, not to empty your breasts.
- Avoid giving your baby formula feeds or other fluids unless you’ve been advised to by a health care professional.
- Avoid placing any pressure on your breasts when you’re feeding.
- Aim to rest during the day when your baby is asleep.
Resources and support
See your doctor, a lactation consultant or your child health nurse for support. They will be able to watch your baby feeding and give you some guidance on attaching your baby for feeds.
Speak to a maternal child health nurse
Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available 7am to midnight (AET), 7 days a week.
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Last reviewed: June 2022