Can I breastfeed with a fever?

The verdict

Yes. A fever is a sign that your immune system is working, not a sign that your milk has changed. There is no mechanism by which a raised body temperature curdles, sours or contaminates breast milk, and no UK, US, Irish or Australian authority treats maternal fever on its own as a reason to interrupt feeding.

The useful question is not whether you can feed. It is what is causing the fever. That answer changes what you do next, and it is the reason this page spends more time on causes than on feeding.

Why the milk is fine

Fever is a systemic response to infection or inflammation. It does not alter the composition of milk in any way that matters to a baby, and the organisms causing most common fevers are not transmitted through milk at all. Respiratory and gastrointestinal viruses are passed by droplets, hands and surfaces.

What does pass into milk is the immune response. The American Academy of Pediatrics describes breast milk as delivering antibodies and immune factors that protect the infant against infection, which is why the period when you are most infectious is also the period when your milk is most useful.

La Leche League GB makes the exposure point directly: your baby will already have been exposed to the illness before you realised you were ill. A fever that appears on Tuesday reflects an infection that arrived days earlier. Stopping feeds on Tuesday removes protection without removing exposure.

Finding the cause

In the weeks and months after birth, a handful of causes account for most fevers, and they need different responses.

Mastitis

The one you must rule out first. A red, hot, painful, often wedge-shaped area of breast plus flu-like symptoms and a temperature is mastitis. The NHS is explicit that the main thing is to continue breastfeeding, even though it may be painful, and that even if you do have an infection, breastfeeding will not harm your baby, although your milk may taste a little salty. It also says that if symptoms do not improve within twelve to twenty-four hours of treating it at home, see your GP. Mastitis has its own page here.

A respiratory or gastrointestinal virus

Colds, flu and vomiting bugs all cause fever. None of them is a reason to stop. Both have their own pages, covering hygiene, hydration and what to watch for.

Infection related to the birth

A fever in the first weeks after birth deserves a lower threshold for medical review than a fever later on. Wound infection after a caesarean or perineal repair, retained placental tissue, urinary infection and endometritis all present with fever, and they need treatment rather than watchful waiting. Foul-smelling discharge, heavy or renewed bleeding, or abdominal pain with fever should be assessed promptly.

What to do while you are feverish

Feed on demand. Suppressing feeds while feverish risks engorgement, which risks mastitis, which causes more fever. The direction of that loop only runs one way.

Drink more than feels necessary. La Leche League GB advises keeping up your fluid intake to prevent dehydration even if you cannot eat, and a fever raises fluid losses on top of the demand that milk production already makes.

Feed in the least effortful position available. Feeding lying down on a bed prepared to be safe is usually easier than sitting up through every feed when you are aching, and our page on feeding lying down sets out the Lullaby Trust and Unicef UK conditions for doing that safely. If there is any chance you might fall asleep, prepare for that before it happens rather than after.

Hand hygiene and tissues do the work that stopping feeds would not. La Leche League GB recommends using tissues and binning them immediately, and washing hands with soap and water or using hand cleansers.

On fever-reducing medicines

We publish no doses on this site. The general point worth making is that the usual first-line options for pain and fever in adults are well studied in breastfeeding and are not usually a reason to interrupt feeding, but the specific answer depends on the product and on you. The Breastfeeding Network's Drugs in Breastmilk service answers exactly this question for UK parents. LactMed, the National Library of Medicine's free database, covers it internationally. A pharmacist can look at the actual packet.

When to get urgent help

The NHS sepsis guidance matters here, because postnatal sepsis is the reason not to sit out a high fever. Seek urgent help for confusion, slurred speech, blue, grey, pale or blotchy skin, lips or tongue, a rash that does not fade under a glass, difficulty breathing, or not passing urine all day. A very high temperature, shivering uncontrollably, or feeling that something is seriously wrong all justify calling rather than waiting.

Fever that persists beyond a couple of days without an obvious cause, or fever with breast symptoms that is not improving on the timescale the NHS gives for mastitis, needs a clinician rather than another night of paracetamol and hope.

Where guidance differs

There is no meaningful international disagreement on maternal fever and breastfeeding.

The UK, through the NHS, treats continuing to feed as the default even with breast infection.

The US, through the American Academy of Pediatrics, states that few infections prevent breastfeeding, including mastitis.

Australia, through the Australian Breastfeeding Association, and Ireland, through the HSE, give the same advice, with the same emphasis on continued milk removal when the breast is involved.

The only real variation is in how quickly each system wants you seen, and that is a matter of local access rather than a disagreement about milk.