Mastitis - Symptoms, Treatment and Prevention for Breastfeeding Mums

Making Sense of Mastitis

Sometimes it seems like every new mum you talk to warns you about mastitis. While it may seem like a majority of women get breast infections, it only affects between 3 percent and 20 percent of breastfeeding mothers. Breast pain, however, is the most common reason for premature weaning. So, learning to quickly recognise and appropriately treat mastitis can preserve breastfeeding for mum and baby.


Typically mastitis occurs within the first six weeks after baby’s birth. It can happen anytime, though, especially if feeding patterns change abruptly. Symptoms seem to come on quickly, and the infection is typically limited to one breast.

Mastitis is caused by milk stasis - for whatever reason, milk just isn’t moving and is slowed or stopped in one area of the breast. It is defined as an infection of the breast that may or may not be bacterial. According to the Academy of Breastfeeding Medicine, symptoms of mastitis are a “tender, hot, swollen, wedge-shaped area of the breast associated with temperature of 38.5 C or greater, chills, flu-like aching, and systemic illness.”[1]

Occasionally a woman will develop a sore, swollen, red lump in one breast. If it’s not accompanied by flu-like symptoms, it is probably a plugged duct. Starting treatment as soon as you notice the plug will keep it from progressing to a full-blown case of mastitis.

Factors that increase your likelihood of mastitis include

  • cracked nipples from a poor latch
  • nipple bleb
  • recurrent plugged ducts
  • scheduled or missed feedings
  • poor milk transfer
  • maternal or infant illness, especially with a hospital stay
  • oversupply
  • abrupt weaning
  • breast pressure (from a bra, clothing, seat belt, purse strap, etc.)
  • stress and fatigue


If you believe you have mastitis, be sure that you continue feeding on the affected side. The milk will not harm your baby, even if you do have an infection. Frequent milk removal is an essential part of your treatment. If it’s too painful to nurse on the affected breast, you will need to pump or hand express milk to keep the milk moving. Other treatments you can start at home include:

  • Rest: Tuck yourself into bed with your baby and do nothing but nurse and rest. Get help - you’ll need someone to care for the baby while you’re sleeping, though they should bring baby to you as soon as he is hungry.
  • Massage: While your baby is nursing (or while you are pumping), massage the affected area of the breast gently toward the nipple. You can do this between feedings, as well. Therapeutic breast massage is another helpful tool - you can learn more about how to do it here.
  • Warm compresses or a heating pad may be helpful immediately before feeding or massaging the breast.
  • Some women prefer cold compresses between feeding for relieve of swelling.
  • An over-the-counter pain reliever may help. Just check with your GP or pharmacist that it is compatible with breastfeeding.
  • Eat well and stay hydrated during treatment.

Other less common home treatments include the use of poultices or tinctures (made from potatoes, rosemary, fenugreek seed, dandelion, Echinacea, or Oregon grape root). Always consult with an herbalist or naturopath for the correct dosages. You may want to increase your vitamin C intake to boost your immune system, and consider a lecithin supplement if you have a history of plugged ducts. You can use raw garlic - two to three raw cloves per day chopped into small pill-sized pieces and swallowed whole - as another home remedy. Experts recommend eliminating saturated fats from your diet, especially if you are prone to repeated mastitis.

While most cases of mastitis improve on their own, if your symptoms don’t begin to improve within 24 hours, you should see your doctor for an antibiotic. You may need antibiotics immediately if you have mastitis in both breasts, if your baby is younger than 2 weeks old, if you have been recently hospitalised, if you have signs of infection in broken nipple skin (pus, drainage, etc.), or if you have red streaks on your breast.

Side Effects

The most common side effect of mastitis is premature weaning. In addition, you may notice that any expressed milk looks lumpy, stringy or like gelatin. You can strain out these bits before feeding the milk to your baby. Occasionally milk may contain blood, pus or mucus - it’s still safe for your baby’s consumption. Your milk may taste saltier, and your baby may refuse the affected breast. Be sure you pump or hand express on that side if this happens to you. Sometimes milk supply decreases during a bout of mastitis, but will improve again once things are back to normal. You may find that your breast feels bruised or looks red for a week or more after the acute mastitis has resolved.

It can take a week or more for a lump from a plugged duct to disappear completely. As long as it continues to get smaller no additional treatment is necessary. About 3 percent of women with mastitis, though, develop a fluid-filled cyst called a breast abscess. If mastitis symptoms do not fully resolve after treatment, abscess should be suspected. Treatment for breast abscess includes fluid drainage and antibiotics.


The best prevention for mastitis is making sure your baby is positioned and latching well from the start. Getting the help of a lactation consultant in the first days after birth can help you to adjust baby’s latch for comfort and so that baby can adequately remove milk from the breast. Learning to recognise milk transfer and what to do if your baby isn’t feeding well is an essential mothering skill from birth. Feed your baby frequently and be sure to treat any breast pain as soon as it becomes apparent so that it doesn’t proceed to an infection.

Some recent research has been undertaken to determine if regular use of specific strains of probiotics can help prevent mastitis. While you may see products sold for this purpose, the research is inconclusive and has methodological flaws. While probiotics may not prevent mastitis, you may want to include them in your daily regimen when taking antibiotics to replace the good bacteria that will be killed by the medication and to prevent a vaginal or breast yeast infection.

As your baby gets older, mastitis isn’t as likely, but it does still occur. Any time feedings patterns change - for instance, if mum or baby is sick, if mum returns to work, if baby is weaning, etc. - the stage is set for milk stasis and mastitis. Be sure to remove milk from the breasts often if you and baby are separated, and to wean from the breast gradually once you reach that point in the course of your breastfeeding relationship.

Often, cases of recurrent mastitis are actually just one infection that hasn’t been adequately treated. Other factors that can contribute to multiple mastitis infections include unrelieved stress and fatigue, anemia, maternal allergies, food intolerances, smoking, too much or too little salt in mum’s diet, and a history of breast surgery or injury. Investigating these areas may help you prevent future infections and have a comfortable nursing experience.

[1] Amir, L. H., & Academy of Breastfeeding Medicine Protocol Committee. (2014). ABM clinical protocol# 4: Mastitis, revised March 2014. Breastfeeding Medicine, 9(5), 239-243.