
Whether pregnant and preparing for breastfeeding or currently in the thick of it, you must know the early warning signs of the common breast infection, mastitis.
There’s usually a lot to learn about breastfeeding, including what can happen to your breasts if something is amiss, like mastitis.
This article outlines mastitis, why it happens, the warning signs, and what to do if you suspect you have it.
Note: this post is for informational purposes only and does not substitute medical adfice. Please contact your care provider if you believe you need further care.

What is mastitis?
Mastitis is a severe infection that is caused by bacteria getting into the breast in one of two ways:
- Through a crack in the skin or nipple,
- Stagnant milk is left from not draining your breast or blocked from a clogged duct.
Mastitis usually only affects one breast at a time, but it can seriously impede your breastfeeding journey if you don’t take the proper steps to care for it. It is painful and often leaves you feeling very sick.
Unfortunately, mastitis is pretty common. One study found that as many as one in four breastfeeding women will experience it within the first 26 weeks of postpartum.
The good news is once it is diagnosed, your doctor can treat it quickly.

Six common mastitis symptoms to look for
Here are the most common symptoms of mastitis and a comprehensive guide to the beginning feelings of mastitis.
Mastitis warning signs at a glance:
- Breast lumps
- Breast pain, heat, or burning
- Skin redness
- Nipple discharge
- Flu-like symptoms
- Nausea or vomiting
1. Breast lumps
While a breast lump itself doesn’t always equal mastitis, it could signify a clogged milk duct. If left untreated, clogged milk ducts can lead to bacteria growth in the stagnant milk and quickly cause an infection.
Frequent and regular breastfeeding is the best way to clear a clogged milk duct and prevent mastitis. You can also try gently massaging your breast or using a lactational massager while pumping or feeding to help the clog loosen up.
2. Breast pain, heat, or burning
Typically one of the first symptoms of an infected breast is that it will feel swollen, hot, or tender to your touch.
It’s normal for your nipples and breasts to feel sensitive or tender in the early days of breastfeeding. What is NOT normal is painfully swollen breasts or intense pain.
Many mothers with mastitis describe the feeling as a burning pain deep within their breasts. This pain may be constant or only when you breastfeed or pump.

3. Skin redness
Another common sign of mastitis is redness on the breast. In the case of severe infections, the redness may be in the shape of a wedge, taking up a large portion of your breast.
Remember that this symptom is often missed in mothers with darker skin tones. Inflamed skin will not look the same for everybody, leading to misdiagnosing women of color. Please advocate for yourself if you notice any breast skin changes.
4. Nipple discharge
Mothers experiencing mastitis may also notice an abnormal discharge coming from their nipples. This discharge may be white, or you could see a bit of blood in it.
It’s important to note that blood from your nipple (whether it’s from an infection or cracked skin) will not harm your baby. It’s important to continue breastfeeding or pumping, even if blood is present.
Catching mastitis early is crucial for a swift recovery, so be sure to call your doctor or lactation consultant immediately if you have any warning signs.
5. Flu-like symptoms
If you are experiencing flu-like symptoms, this is a sign that the mastitis infection has likely set in. You may develop a fever, body aches, pains, chills, or headaches.
You should always notify your doctor if you experience a fever or flu symptoms anytime during your postpartum period. This is not normal.
6. Nausea or vomiting
Nausea and vomiting is another severe symptom of mastitis, which typically means you have an infection. If you are vomiting during your postpartum period, always tell your doctor.

Breast milk supply and mastitis
If you notice these symptoms and suspect you have mastitis, it’s important to keep breastfeeding or pumping. This will protect your milk supply and keep the milk flowing through the ducts and prevent more bacteria from growing.
You may find that your milk production decreases slightly while your breasts are inflamed, but don’t worry. It will come back if you continue to drain your breasts frequently.
Remember, the milk from your affected breast will not harm your baby, and it’s essential to keep it flowing.
When to call your doctor with mastitis
Catching mastitis early is crucial for a swift recovery, so be sure to call your doctor or lactation consultant immediately if you have any warning signs.
Generally, any breast change is reason enough to call your doctor.
If the infection has set in, your doctor may prescribe you antibiotics. You must follow their instructions and complete the entire medication dose to fight the properlydisease.
Managing mastitis pain at home
Until you see your doctor and receive their recommended treatment, here are some ways you can manage pain:
- Apply a warm, moist compress or have a warm shower.
- Gently massage the affected breast.
- Drink plenty of fluids and rest.
- Avoid wearing tight and restrictive bras or clothing.
Remember, you can always reach out to a medical professional if you have questions or feel concerned about anything.
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Macy Tollefson is a full-spectrum doula, breastfeeding specialist, and certified prenatal yoga teacher. She is passionate about guiding the modern mama through the beautiful (and wild) transformation of pregnancy, birth, and postpartum. With over 100 hours of breastfeeding education, Macy is about setting mothers up for success on their baby-feeding journey and helping them find their flow. She believes that yoga and meditation have the power to enhance any part of your motherhood journey.