Mastitis Dr Trisha Macnair Mastitis, or inflammation of breast tissue, is a miserable condition that often adds to the stress of motherhood. It can occur in women at other times, but is more likely to develop during breastfeeding.

In this article

What causes it? What are the symptoms?

What's the treatment? How can I avoid it?

There are three principal causes: infection, which accounts for about half of cases, engorgement and blocked ducts. An infection is almost always bacterial, sometimes as a result of a cracked nipple, and antibiotics may be needed if the infection does not resolve itself without treatment.

Infection usually produces the worst symptoms. The breast becomes red, hot, swollen and shiny and the nipple may produce pus. More general symptoms include high fever, shivers, muscle aches, nausea and vomiting.

With engorgement, mastitis develops because the breasts are not emptying properly at each feed. They become swollen, lumpy, sore, leaky and tense. Superficial ducts full of milk may appear like hard cords along the surface of the breast, and both breasts may be affected. Though painful, the symptoms are not usually as severe as with infection. There may be some general symptoms such as feeling hot, uncomfortable and thirsty.

Blocked ducts tend to cause a more localised problem, resulting in an area of tender, hard lumpiness where some of the breast tissue does not empty of milk. Occasionally, especially in severe cases, there may be general flu-like symptoms.

When the baby feeds, the normal let-down reflex means there's even more pressure behind the blocked duct from milk trying to leave the breast, which means feeding can be very painful.

If you develop a painful, red or swollen breast, and especially if you have generalized symptoms such as a fever, it’s important to see your doctor because there may be infection that needs treatment with antibiotics.

You should try to continue breastfeeding. Although mastitis may interfere with breastfeeding - because the breasts become distorted in shape, for example – it is often the best treatment because it empties the breast.

In fact it's important to persevere, because otherwise engorged breasts rapidly lead to a fall in milk production, as the body sees it as a signal that more milk is being produced than is needed.

With engorgement, if the affected area is not drained there's a risk of infection developing. Try to give frequent feeds varying the position of the baby (many recommend a position where the baby's chin points towards the affected area). Offer the affected breast first for the best chance of good drainage.

You can also try massaging the affected area of the breast as you feed, and applying warmth to the area.

There's no risk to the baby from infection being passed on in the milk, so this is not a reason to stop feeding.

You can try to relieve the symptoms with cooling treatments - everything from cabbage leaves to cold flannels to gel-filled cool packs. Gentle breast massage can also help. If there is no infection, medicines are often not very effective in resolving the mastitis but may help with symptoms.

Paracetamol or ibuprofen may ease pain and reduce fever for example. These are usually safe although ibuprofen can get through into breast milk in small amounts - this doesn't usually do any harm but you should check with your GP if your baby was born prematurely, had a low birth weight or any other medical problems. Paracetamol can also pass through into breast milk in tiny amounts but is thought to be even less likely to do harm.

To lower your risk of mastitis, try to:

• Ensure you empty your breasts fully at each feed - express any milk left when your baby's had enough
• Feed on demand or more frequently if your breasts feel lumpy after a feed
• Mastitis often develops when the baby's not latching on properly, so ask your midwife/health visitor for advice
• Try to get regular rest - don't let your immune system get ground down
• Try not to stop breastfeeding if you have a problem

This article was last medically reviewed by Dr Trisha Macnair in April 2009.