Patient education: Mastitis (The Basics)

What is mastitis? — Mastitis is when part of the breast becomes inflamed and swollen.

Mastitis often happens in people who are breastfeeding. The medical term for this is "lactational mastitis." It is most common during the first few months of breastfeeding. But it can happen at any time.

Swelling in the breast can make it harder for milk to flow. The goal of treatment is to ease discomfort and get the milk flowing again. If milk flow stays blocked, mastitis can lead to infection.

What is engorgement? — When a person is breastfeeding, special glands in the breasts make milk. From there, the milk flows into the "milk ducts" and out through the nipple (figure 1).

"Engorgement" is swelling that can happen in the tissue around the ducts. This typically happens when the milk first comes in, within a few days of birth. It makes both breasts full and painful. If your body makes more milk than your baby eats, this can also lead to engorgement.

Any time engorgement happens, it is relieved by breastfeeding regularly. Make sure that the baby has a good "latch" on the nipple.

What causes mastitis? — Mastitis is similar to engorgement, but usually affects 1 breast. The swelling in the breast puts pressure on the milk ducts. This makes the ducts narrower, so milk cannot flow to the nipple as easily.

You might be more likely to get mastitis if:

●Your baby is not able to remove enough milk when feeding.

●You have an injury to your nipple, like cracked skin or a blister.

●You have "oversupply," meaning that your body makes more milk than your baby eats.

What are the symptoms of mastitis? — The early symptoms are similar to breast engorgement, but often only affect 1 breast. They include:

●A hard, red, or swollen area of 1 breast

●Breast pain or tenderness

If milk flow is blocked for more than a day or 2, this can lead to bacterial infection. Breast milk normally contains bacteria. This type of bacteria is not harmful for a baby. But if it builds up in your breast, it can cause an infection. This is called "bacterial mastitis."

In addition to breast redness, swelling, and pain, bacterial mastitis can cause:

●Fever or chills

●Muscle aches

●Tiredness

Will I need tests? — It depends. Your doctor or nurse will ask about your symptoms and do an exam. This can usually tell them if you have mastitis.

In certain cases, doctors might do tests. This is more likely if you have severe symptoms or an infection that is not getting better with antibiotics. Tests might include:

●Tests on a sample of breast milk – If you have an infection, this can show what kind of bacteria caused it. In some cases, this can help doctors decide what antibiotic to prescribe.

●Ultrasound – This is a type of imaging test. It creates pictures of the inside of the breast. An ultrasound can show if you have a breast abscess. (An abscess is a collection of pus that can form if infection is not treated.)

Is there anything I can do on my own to feel better? — Yes.

You do not need to stop breastfeeding if you have mastitis. Regular breastfeeding is actually the best way to help with swelling and keep milk from getting blocked again. Even if you have an infection, you will not pass it on to your baby.

To help relieve symptoms, you can:

●Feed your baby when they are hungry. If milk is flowing from the breast with mastitis, you can feed your baby on that side.

●Only use a breast pump if you need to. Do not try to empty your breast completely, as this can make mastitis worse.

●Avoid using nipple shields.

●Hold a cold compress on your breast. This can help with both pain and swelling. Some people find that a warm, wet cloth on the breast feels better than cold. Use whichever feels better.

●Take acetaminophen (sample brand name: Tylenol) or ibuprofen (sample brand names: Advil, Motrin) to help with pain or fever. Do not take aspirin.

●Gently massage your breast to help unblock the milk ducts. Start at the part of the breast that is swollen or sore, and stroke gently toward your nipple. This can help improve milk flow.

●Wear a bra that is supportive and fits well, but is not too tight.

●Drink plenty of fluids.

●Rest when possible.

How is bacterial mastitis treated? — Mastitis does not always lead to infection. But when it does, the infection is treated with antibiotics. This usually involves taking antibiotic pills for at least 5 days. Some people need to take them for up to 2 weeks.

If your infection is severe, you might need treatment in the hospital. This involves getting antibiotics through an IV, which is a thin tube that goes into a vein.

Can mastitis be prevented? — Sometimes. To lower the risk of getting mastitis:

●Breastfeed your baby regularly.

●If you use a breast pump, do not over-pump. Do not try to empty the breast completely.

●Work with a lactation consultant if you are having trouble breastfeeding. They can help with things like nipple pain, problems with your baby's latch, or milk supply issues.

●When you are ready to stop breastfeeding, do this gradually. Do not stop breastfeeding all at once.

When should I call the doctor? — Call for advice if:

●Your symptoms do not get better after 1 to 2 days.

●You start having symptoms of infection, such as fever, muscle aches, or feeling very tired.

●You are struggling with breastfeeding.

You can also talk to a lactation consultant (breastfeeding expert) for help.

More on this topic

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Patient education: Breastfeeding (The Basics)
Patient education: Pumping and storing breast milk (The Basics)

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