Breast Mastitis

Breastfeeding can be a special bonding experience between parent and baby. However, it’s not always easy. One common challenge some nursing parents face is mastitis. This condition may cause breast pain, swelling and flu-like symptoms.

At Banner Health, our team is here to help you manage and treat mastitis. We’ll explain mastitis, its symptoms, causes and treatment options. 

What is mastitis?

Mastitis, or lactation mastitis, is the inflammation or swelling of breast tissue. It can sometimes lead to a breast infection. In the U.S., about 1 in 10 breastfeeding people will experience mastitis. 

While mastitis most often affects people who are breastfeeding, it can rarely occur in those who are not. 

Mastitis can cause: 

• Breast pain, swelling and redness 
• A warm or tender area on the breast 
• A fever and flu-like symptoms 
• Fatigue or feeling unwell 

Mastitis may lead some babies to wean earlier than planned. However, continuing to breastfeed while being treated—if possible—is often best for both you and your baby, even if you're taking antibiotics.

What causes mastitis?

The most common cause of mastitis is blocked milk ducts. If a breast does not empty, a hard lump may form. If the blocked duct isn’t cleared, trapped milk sitting in the breast (called milk stasis) can cause bacteria to grow, leading to an infection.

Other causes include: 

• Bacteria from your skin or baby’s mouth entering through a cracked nipple or milk duct 
• Pressure from a tight bra or carrying a heavy bag 
• An oversupply of milk 
• Nipple damage or improper latching 
• Skipping feedings or not fully draining the breast 

Who is most at risk for developing mastitis?

You may be more likely to develop mastitis if you: 

• Have an oversupply of breast milk 
• Always use the same position to nurse 
• Wear tight bras or clothes that put pressure on your breasts 
• Have cracked or damaged nipples 
• Don’t fully empty your breasts 
• Have had mastitis before 
• Have a condition like diabetes or another autoimmune disorder 

Smoking, high stress and poor nutrition can also raise your risk. 

Symptoms of mastitis

Symptoms of mastitis can come on quickly. They may include:

• A sore breast or nipple
• Burning sensation while breastfeeding
• Swelling and redness in a specific area of the breast
• Warmth in the affected area
• A hard lump in one breast
• Feeling tired
• Body aches and flu-like symptoms, including fever and chills

See your health care provider or a Banner Health specialist if you notice these symptoms.

How is mastitis diagnosed?

Your health care provider will: 

• Do a physical exam and gently check for pain or lumps 
• Ask about your symptoms 
• Possibly collect a small sample of breast milk to check for infection 

In some cases, an ultrasound may be used to check for complications such as a breast abscess (a pocket of pus) or other breast conditions. 

Mastitis treatment

Treatment focuses on easing symptoms and treating infection. Your provider may recommend: 

• Cold compresses: Apply a clean, cold pack or frozen vegetables wrapped in a towel to reduce swelling and relieve pain. Use for 15 minutes several times a day. 
• Hydration and rest: Drink fluids and rest as much as possible to help your body heal. Ask for support from others when needed. 
• Over-the-counter pain relievers: Ibuprofen or acetaminophen can help relieve pain and reduce inflammation. Follow package directions or ask your provider. 
• Comfortable clothing: Wear loose clothes and a supportive, non-restrictive bra. Avoid anything that puts pressure on your breasts. 
• Breastfeeding or pumping: Continue to breastfeed or pump to help empty your breasts. Start feeding on the affected side to use your baby’s stronger sucking to clear the blockage. 
• Talk to your provider: If symptoms don’t improve within 24–48 hours, or if they get worse, contact your provider. You may need antibiotics to treat the infection. 

You should start to feel better within 48–72 hours. Most infections clear within a week to 10 days. 

What to avoid

To help mastitis heal and avoid making it worse: 

• Avoid heat: Hot showers and heating pads can increase inflammation. 
• Skip deep massage: Firm massage may damage breast tissue. Use gentle pressure instead. 
• Don’t soak your breasts: While Epsom salt soaks may relieve pain, they can also dry or damage nipple tissue. 
• Don’t skip feedings or pumping: This can lead to more swelling or infection. Keep draining your breasts regularly. 

Complications of mastitis

If left untreated, mastitis may lead to a breast abscess. This type of abscess may require minor surgery or use of a small needle to drain the pus from the milk duct.

How to prevent mastitis

Preventing mastitis is often about maintaining good breastfeeding habits and taking care of your breasts. Here are some tips:

1. Breastfeed or pump regularly: Follow a schedule. Letting milk build up can lead to engorgement and increase the risk of mastitis. Try to empty your breasts entirely during each feeding or pumping session.
2. Ensure a good latch: A proper latch helps your baby remove milk from your breast effectively, which can prevent blockages. If you’re having trouble with latching, speak to a lactation specialist or attend a Banner Health lactation support class.
3. Avoid tight bras and clothing: Wear a comfortable, well-fitting bra without underwires to prevent pressure on your breasts. Also, avoid sleeping on your stomach or carrying heavy bags that press against your chest. 
4. Practice good hygiene: Wash your hands before breastfeeding or pumping to prevent bacteria from entering the breast area. Keep your nipples clean and dry. Avoid using nipple shells or other devices on your breasts.
5. Maintain a healthy diet: Drink plenty of water and eat a balanced diet to keep your body strong and healthy. Proper nutrition helps maintain a good milk supply and supports your immune system. 
6. Rest when you can: Being overly tired can weaken your immune system. Try to rest whenever possible and seek support from family and friends.

These tips can lower your chances of developing mastitis and enjoy a smoother breastfeeding experience. If you notice signs of mastitis, see your health care provider to address them. If you have challenges with breastfeeding, see a lactation specialist or attend a breastfeeding support class.

Don't wait for care

If you’re struggling with mastitis or other breastfeeding challenges, Banner Health is here to help. Our expert providers and lactation specialists offer personalized support and care to help you heal and continue breastfeeding with confidence.

Schedule an appointment today.