Thrush is a type of yeast infection. It may sometimes occur in breastfed babies and on the nipples of breastfeeding women.

Thrush is caused by an overgrowth of Candida albicans, a fungus that lives in the digestive tract and on skin. Candida is a naturally occurring organism. It doesn’t usually cause any problems, but if it multiplies uncontrollably, thrush can occur.

In women who are breastfeeding, thrush can lodge in the nipples, areolas, and breasts, causing significant pain. This may be more likely to occur if your nipples are cracked and open. You may also be more likely to get thrush in your breasts if you have a vaginal yeast infection.

Nursing babies can get thrush in their mouths and on their tongues. This is referred to as oral thrush. Oral thrush in babies can be painful. Your baby may be fussy or have trouble feeding if they have oral thrush. Oral thrush is common in infants under 6 months old.

Thrush on the breasts

Thrush on the breasts may cause pain during and after feeding. For some women, the pain can be extreme.

The pain may be isolated in the nipples or behind the areolas. It may also radiate throughout the entire breast for up to an hour after nursing.

Additional symptoms may include:

  • itchy nipples
  • pale-looking nipples and areolas, or white areas on the nipples and areolas
  • temporary or long-lasting burning sensation in the nipples
  • shiny skin on or around the nipples
  • flakes on the nipples and areolas

Oral thrush in babies

Symptoms of this condition in babies may include:

  • white, milky-looking patches on the gums, tongue, inner cheeks, and tonsils, which bleed easily when touched
  • irritated, red skin in the mouth
  • cracked skin in the corners of the mouth
  • diaper rash that won’t go away

Thrush can be caused by Candida overgrowth. Overgrowth can occur if the healthy bacteria in your body can’t keep the fungus under control. It can also happen if your immune system is weakened or immature. Babies are more susceptible to oral thrush because they don’t have a fully developed immune system.

Thrush is also highly contagious. Breastfeeding mothers and babies can get into an ongoing cycle of reinfecting each other through feeding. It’s important that both mom and baby get treated when infection occurs.

If you have thrush, your breast milk, as well as anything that touches your breasts, can spread the bacteria. This includes:

  • hands
  • nursing bras
  • nursing pads
  • clothing
  • towels
  • burp clothes

If your baby has thrush, anything they put in their mouth can also spread thrush. It’s important to sterilize pacifiers, teething rings, and bottle nipples to avoid this.

Oral thrush from your baby can also be transmitted to your breasts during feeds. You can also get it from changing your baby’s diapers if the fungus is in their stool.

You may also be more susceptible to getting thrush on your breasts if you have a vaginal yeast infection.

You may be at increased risk if you’re taking certain medications, such as antibiotics, corticosteroids, and certain types of cancer drugs. These drugs, and others, can destroy healthy bacteria, making thrush more likely to occur.

High blood sugar levels can also lead to yeast overgrowth. Women with diabetes are at increased risk for developing thrush than women without this condition.

If you suspect that you or your baby have thrush, you should both be seen by a doctor. Some cases of oral thrush may resolve without treatment, but treating the condition is the only way you can be assured of breaking the reinfection cycle.

Your doctor will diagnose oral thrush by gently scraping any lesions found inside the mouth and examining them under a microscope. A pediatrician may also examine your baby’s diaper area to determine if thrush has spread to other areas of the body.

To diagnose thrush on the breasts, your doctor will examine your breasts and asking about your symptoms. You may also need a blood test to rule out other types of infection.

Your doctor may also want to rule out problems which might be causing you breast pain, such as improper latching, before making a diagnosis.

Thrush can be treated with antifungal medication. Your doctor may prescribe a topical antifungal cream to apply to your breasts, such as miconazole cream (Lotrimin, Cruex).

Some topical antifungals are appropriate for oral use, but others will need to be cleaned off your breast prior to letting your baby nurse. Ask a doctor or pharmacist if the cream you’re using is safe for your baby.

You may also be prescribed an antifungal medication to take in pill form.

If you have diabetes, your doctor will want to make sure your blood sugar is under control. Even if you don’t have diabetes, your doctor may recommend reducing your sugar intake, including refined carbohydrates, until the infection resolves.

If the infection is causing pain, talk to your doctor about the types of pain medication you can use while breastfeeding.

Your baby will be given an oral gel that you can apply to the inside of their mouth. Most oral gels are not readily absorbed by breast tissue, so make sure you get and use your own prescription, too.

Thrush may reduce your milk supply. It may also be harder to breastfeed while you and your baby are experiencing symptoms. However, you can continue to breastfeed during treatment. Continuing to breastfeed can help maintain your milk supply.

It can take up to two weeks for thrush to dissipate completely. Make sure you take all of your medication and practice good hygiene to avoid having a recurrence. Also toss out any milk you expressed and stored while you were infected.

There are several strategies you can use to try and prevent thrush:

  • Wash your hands often, especially after breastfeeding and changing diapers.

  • Try to reduce stress. High levels of chronic stress might adversely affect your immune system.
  • Eat a balanced diet and reduce your sugar intake.
  • Sterilize everything your baby puts in their mouth, such as pacifiers or teething toys.
  • Keep your nipples dry between feedings. When possible, remain topless for several minutes after breastfeeding to allow your nipples to air dry.
  • If you use breast pads, use the kind without plastic liners. These can trap in moisture, making you more susceptible to thrush.
  • Increase good bacteria levels by eating yogurt daily, or by taking probiotics or a Lactobacillus acidophilus supplement.

Thrush is very contagious and can pass between a breastfeeding mother and a nursing infant. Topical or oral medications can eliminate thrush. Good hygiene and healthy habits can also make it harder to spread.