Staph, MRSA and Breastfeeding

Staphylococcus aureus is the most common bacteria associated with infection in damaged nipples, mastitis or breast abscesses. An increasing number of Staphylococcus aureus bacteria (staph) are resistant to certain antibiotics and are known as methicillin or meticillin-resistant Staphylococcus aureus (MRSA). MRSA may affect a wound or be a more systemic infection (throughout the body). Some people are carriers of staph without having any symptoms of infection. This article looks at the recommendations for breastfeeding if a mother is diagnosed with staph or an MRSA infection.

Staphylococcus aureus infection

Staph is a common bacteria which may be found on the skin or in the nose 1. When a bacterial infection is found in cracked or damaged nipples, infective mastitis or an abscess, penicillin-resistant Staphylococcus aureus (staph or S. aureus) is the most likely bacteria to be cultured. Your doctor will prescribe antibiotic treatment (penicillinase-resistant penicillins) to deal with the infection but breastfeeding can continue 23.

Many health workers are concerned about a possible risk of infection to the infant, especially if the milk appears to contain pus. They recommend manual expression, and discarding of the milk. However a number of studies have demonstrated that continuing to breastfeed is generally safe, even in the presence of Staph. aureus.

The infant should be observed for any signs of infection, and if mastitis is known to be due to staphylococcal or streptococcal infection, simultaneous antibiotic treatment of the infant may be considered.

There is no evidence of risk to the healthy, term infant of continuing breastfeeding from a mother with mastitis. Women who are unable to continue breastfeeding should express the milk from breast by hand or pump, as sudden cessation of breastfeeding leads to a greater risk of abscess development than continuing to feed.

If there is no improvement after two days of antibiotic treatment or the infection keeps coming back, breast milk cultures can be taken to check the nature of the bacteria and identify the antibiotic sensitivity of the bacteria. MRSA is increasingly being identified in these cases and requires different antibiotics (ABM, 2014).

Mother holds newborn baby just after birth
Skin-to-skin contact with mother colonises baby with protective bacteria

MRSA and breastfeeding

There are different recommendations for MRSA and breastfeeding depending whether your baby is full term or premature and whether the MRSA infection is on the breast or somewhere else on the body.

If your baby is full term and healthy

Many breastfeeding experts recommend that if a mother has a MRSA infection, her healthy, full term baby can continue to breastfeed while his mother, or mother and baby, receive treatment 456. Any areas of skin with a MRSA infection should be kept covered so the baby doesn’t have any contact with them. And careful hygiene is recommended such as washing a mother’s and baby’s hands before breastfeeding, sterilising pump parts and nipple shields, and using disposable breast pads (Mohrbacher 2010; ABM 2014).

Let your doctor know if you have, or have had, MRSA, as this may help with prescribing appropriate treatment. Repeated use of ineffective antibiotics increases the risk of a breast abscess. If a breast infection recurs, and especially if you took a full course of antibiotics, ask your doctor to arrange for cultures of your milk and your baby’s throat to determine an effective antibiotic treatment for you and/or your baby. If you need treatment for MRSA you can continue to breastfeed.

MRSA Action UK adds:

You can usually continue to breastfeed a healthy term baby in the community, unless you have been told not to breastfeed until any antibiotic therapy is complete. If baby is in neonatal care and at significant risk of developing an invasive MRSA infection, consider withholding breast milk until the MRSA mastitis has cleared up. Risk factors include IV catheters, ventilation, recent surgery or a low immune system.

If baby is poorly or premature

If a mother has MRSA and her baby is premature, poorly or in the neonatal unit it may be necessary to interrupt breastfeeding until the infection clears. As stated above, careful hygiene such as hand washing and covering any open wounds is important to avoid spreading the infection. Nancy Mohrbacher explains:

if a mother develops a MRSA infection, the baby has already been exposed to it before her symptoms became obvious, so there is no reason to stop breastfeeding unless the baby is ill or preterm. If the baby’s health is fragile, the mother’s milk can be pasteurised before feeding 78, or if that is not an option, her milk may need to be discarded until it is clear of infection, usually within 24 hours of treatment 9.

Authors Lawrence and Lawrence state:

When infants in NICUs (premature, LBW or VLBW, and/or previously ill) or their mothers have a MRSA infection, those infants should have the breast milk cultured and suspend breastfeeding or receiving breast milk from their mothers until the breast milk is shown to be culture-negative for MRSA. The infant should be treated as indicated for infection or empirically treated if symptomatic (with pending culture results) and closely observed for the development of new signs or symptoms of infection. Pumping to maintain the milk supply and the use of banked breast milk are appropriate.

When the MRSA infection is on the breast

If an active MRSA staph infection is on the breast opinion varies on how to proceed.

Canadian paediatrician and breastfeeding expert Dr Jack Newman favours continued breastfeeding where possible explaining the baby will have already been exposed to the bacteria by the time it is diagnosed:

The best protection for the baby is to continue breastfeeding. This is true even if a bacterial culture shows the mother’s infection is due to MRSA (methicillin-resistant Staphylococcus aureus). Many health care providers have an exaggerated fear of MRSA. True, it is difficult to treat and therefore nasty, but that’s even more reason to keep the baby breastfeeding. The treatment options are limited, because the baby has already been exposed to the bacteria. What will protect him? Continued breastfeeding. The immune factors in the milk will help keep the baby from getting sick or help fight off the infection if he does.

There is further discussion on Jack Newman’s community Facebook page;

First of all, mothers and babies share germs and if the mother gets mastitis, usually caused by Staphylococcus aureus, the baby has already been exposed to the infection, before the mother got mastitis. Bacteria don’t suddenly appear out of the blue and immediately cause infection. It takes time, at least a few days, and the whole time, the mother and the baby are sharing this germ. In fact, mothers have often been colonized with the bacteria for weeks or months even before the baby was born. Even if the bacterium causing the mastitis is MRSA (methicillin-resistant Staphylococcus aureus), this does not mean the mother should stop breastfeeding. The fact of the matter is that the immune protection a baby gets from breastfeeding is not theoretical, it’s real and taking the baby off the breast will only increase his chances of getting sick and more severely sick than if he remained breastfeeding, even on the side of the infected breast.

Interrupting breastfeeding?

If the MRSA infection is close to the nipple or areola some organisations advocate stopping breastfeeding and discarding the milk on the affected breast through the first 48 hours of antibiotic treatment, while continuing to breastfeed on the other breast 1011. Some authors advise interrupting breastfeeding for 24 hours and pumping and dumping breast milk if there is an active infected sore on the breast, or mastitis, an abscess, or surgical incision drainage involving MRSA 1213. I do not currently have any further references for this rationale.

Mothers should be guided by their health professionals for their particular situation. If there is any interruption in breastfeeding on either breast, a mother will need to pump during the interval to keep her milk supply going.

Treatment for MRSA staph infection

Although MRSA is resistant to traditionally used antibiotics there are several medications compatible with breastfeeding that can be used to combat the infection 1415.

The drug of choice for MRSA is vancomycin. It is not effective for breast infections when taken by mouth, so it is given intravenously. Other drugs that may work for MRSA are cotrimoxazole, doxycycline and minocycline. None of these drugs require the mother to interrupt breastfeeding.

The compatibility of any medications with breastfeeding can be checked against one of the resources listed in Medications and Breastfeeding.

Avoiding MRSA infection

The transfer of MRSA infections can be minimised in a hospital birth setting by:

  • Encouraging a baby’s skin-to-skin contact with his mother as soon as possible after birth and frequently thereafter so that baby is colonised with protective friendly bacteria 16
  • Breastfeeding as soon as possible to promote the growth of protective bacteria in baby’s gut
  • Keeping baby with his mother, not in a newborn nursery
  • Avoiding skin-to-skin contact with hospital staff
  • Observing hygiene such as frequent hand washing


Breastfeeding can continue with a staph infection and most breastfeeding resources also recommend continued breastfeeding if a mother is colonised with MRSA and her baby is healthy and full term. Breastfeeding can continue while a mother receives antibiotic treatment for an MRSA infection. If there is an active MRSA infection on the breast, advice varies between continuing breastfeeding through treatment because the baby will have already been exposed to the infection, to stopping breastfeeding for a day or two particularly from an affected breast if the wound is close to the nipple. If a baby is poorly or premature, breastfeeding may need to be interrupted for 24-48 hours while a mother receives treatment. The parents will need to carefully consider their choice of replacement feed during any pause in breastfeeding, in particular the impact supplementing with formula could have on their baby’s immune system at a vulnerable time. Lawrence and Lawrence 17 advocate the use of banked breast milk if a substitute is needed.

Contact your health professional for advice for your situation. This article is not intended as a substitute for medical advice.