When your breastfeeding baby has blood in the stool

It's scary to see blood in your baby's nappy but how worried do you need to be?

Does your baby have blood in her stool?

In brief, streaks or drops of blood in the nappy are common in the first months of babies' lives, are usually harmless, and pass within a couple of months. Despite what you might hear, the latest evidence tells us there's no reason to assume this slight bleeding is allergic. There are however some important things to know.

Please see your GP if your baby has blood in her stools. Your GP will make sure that there is no gastroenteritis, anal fissure, or other concerning medical condition causing the bleeding. Green stools and mucous in the stool are normal for babies, but blood in the stool is something we need to have assessed.

When your breastfed baby is less than six months old and has streaks or drops of blood in or on her poo

Small streaks of blood quite commonly occur in the stool of healthy breastfed babies. This can be alarming for parents! You're most likely to see it in the first eight weeks of life, or otherwise at some time in the first six months.

Research investigations done in babies who have small amounts of blood in the stool often find a temporary patch of mild inflammatory change in the lining of the colon (though not elsewhere in the gut). But researchers and doctors are still not clear about reasons for these changes.

• You can find out why allergy doesn't cause unsettled behaviour in babies here.

• You can find out about how to help babies who cry and fuss a lot in The Possums Sleep Program, starting here.

If your baby is formula fed and has developed a persistent pattern of nappies with streaks of blood in the stool, your doctor may recommend changing to an extensively hydrolysed formula. This is because our formula-fed babies are more likely to have a food-protein-induced allergic proctocolitis. Please discuss this with your doctor.

What is non-allergic benign infantile proctocolitis?

Non-allergic benign infantile proctocolitis is the name given to the mild and temporary inflammation in your baby's colon or rectum which results in streaks of blood in her poo. Your breastmilk, in frequent and flexible doses, is by far the best medicine you can offer. There's no reason to assume these changes are allergic, or related to food proteins in your breast milk, despite what you might hear.

It can help to think of it this way. Eczema is a common inflammation of babies' skin. If the eczema is just a small, mild patch of inflammation, it doesn't cause baby any discomfort or distress at all, and doesn't require treatment. Mild or even moderate eczema is not caused by allergy. Similarly, your baby with streaks or drops of blood in his poo is likely to have a little patch of inflammation in his large gut. But this doesn't cause your baby any discomfort or distress, and is not related to allergy.

We say your baby has benign non-allergic infantile proctocolitis, if baby

• Is under six months of age

• Has small amounts of blood - just streaks or drops - in or on the poo in the nappy.

Even if the streaks or drops of blood occur most days, or in most pooey nappies, it's benign non-allergic infantie proctocolitis, as long as

• The bleeding hasn't gone on for more than two months

• Isn't getting worse.

If your baby fits this picture, then waiting and watching for two months is the approach I recommend, though you would need to discuss this with your own GP first. Only your own doctor can work out with you all that is relevant in your baby's unique situation.

When does allergy cause blood in your breastfed baby's poo?

If your baby with blood in the stool fits any of these five descriptions below, it's important to have your baby assessed by your GP. It is likely that allergy is the cause of blood in your baby's stool, if your baby

1. Is older than six months of age, or

2. Has pink or red stool, or

3. Has large amounts of blood in the stool (that is more than a 'streak' or a 'drop'), or

4. The amount of blood is increasing over time, or

5. The bleeding has gone on for two months without stopping,

What is food-protein-induced allergic proctocolitis?

If your baby shows the above five signs, your doctor will prescribe a cow's milk protein elimination diet, diagnosing food-protein-induced allergic proctocolitis (FPIAP). Here's some things which are helpful to know in this situation.

• If the bleeding resolves after elimination of cow's milk protein, usually within a few days but up to within a fortnight, this is diagnostic of cow's milk FPIAP.

• After the bleeding has resolved, you'd reintroduce cow's milk into your diet. If the bleeding recurs, this further confirms the diagnosis of cow's milk protein allergy.

• If the bleeding continues despite elimination of cow's milk protein, then soy and chicken egg may be removed from the diet, again with re-introduction after bleeding ceases, to confirm the diagnosis.

• Re-introduction of the allergenic protein is usually offered at the latest around three months after your elimination diet was commenced. In very severe cases, re-introduction may need to occur later than that, and your doctor may also consider other investigations.

Partial or exclusively breast milk feeding is protective against true FPIAP, and it's agreed that infants usually outgrow the allergy by one to three years of age. Babies with FPIAP have been found in the research to have a patch (or more) of inflammation in the large gut, which causes the bleeding.

There's no evidence to suggest that also eliminating goat's and sheep's milk proteins will help, although your doctor may consider this worth doing because of the high cross-allergenicity of cow's, goat's and sheep's milk. Soy, egg, and grain protein allergies may occur in babies and toddlers, but are uncommon, and are similarly often overdiagnosed. Soy has a low cross-reactivity with cow's milk protein, despite what you might hear. If other concerning health signs arise, or if the bleeding persists beyond one year of age, your doctors will conduct investigations.

If your baby is formula fed and diagnosed with a true cow's milk allergy, a specialised formula may be required.

What are not signs of allergy (or food-protein-induced allergic proctocolitis) when your baby has blood in the stool?

Sometimes you might hear that there is a cluster of signs which makes the diagnosis of allergy more likely when your baby has streaks of blood in the stool, but this isn't consistent with the latest evidence. The following are not signs of FPIAP or allergy in babies who have blood in their stool.

• Green stool and mucous in the stool are shown in the research to be normal for babies. You can find out about this here.

• Unsettled behaviour is not a sign of allergy. Sometimes blood in the stool occurs in unsettled babies, but their unsettled behaviour is not related to the stool blood, despite what you might hear, unless your baby has copious bleeding or pink stools (which requires medical attention). There is no evidence-based reason to think that a small area of mild inflammation in the large gut causes any kind of pain, and there are many other things to experiment with to help your baby dial down.

  • You can find out why allergy doesn't cause unsettled baby behaviour here.

  • You can find out about crying babies here.

• Vomiting is not a sign of allergy (unless you have a very sick baby with a true food-protein-induced enteropathy syndrome (FPIES), which requires urgent medical attention). You can find about babies and reflux here.

• Eczema is not a sign of allergy (unless it is severe and extensive).

• Inadequate weight gain in babies is a complex problem, and is not due to allergy except when your baby is medically sick with a true FPIES, which is mostly not accompanied by blood in the stool.

What are the possible downsides to overdiagnosing allergy when your baby has blood in the stool?

Cow's milk proteins usually don't occur at high enough levels in the breast milk to trigger allergic reactions in babies, regardless of how much dairy the mother consumes. When a breastfeeding mother is on a dairy elimination diet, she

• Faces the burden of having to eliminate common foodstuffs from her diet, sometimes just at a time when she is often tired and wanting to enjoy dairy every now and then

• Loses the potential nutritional benefits of dairy, including of calcium, and vitamin D. (I acknowledge, however, that there are many people including breastfeeding women, constituting the global majority, who enjoy nutritious diets which don't contain cow's milk!)

When a breastfeeding mother is on an unnecessary dairy elimination diet, there is a greater chance baby will develop a cow's milk allergy down the track.

Although there are babies and toddlers with concerning or even life-threatening allergies to egg, wheat, and soy, and other food proteins too, these are IgE-mediated allergies, not linked to blood in a baby's stool.

• Overdiagnosis of FPIAP and overuse of elimination diets leads to unhelpful dietary restrictions, which adds unnecessary stress and distress to your life with your baby.

• Your baby's behaviour might be interpreted by everyone through the allergy lens. In the meantime, things that really could help dial your baby down and make life easier and more enjoyable for your family (which we deal with in the Possums programs) may not be attended to by your health professionals.

Selected references

Arvola T, Ruuska T, Keranen J. Rectal bleeding in infancy: clinical, allergological, and microbiological examination. Pediatrcis. 2006;117(4):e760-768.

Gelsomino M, Sinatti D, Miceli Sopo S. Non-allergic benign infantile proctocolitis: a neglected nosographic entity. BMC Case Reports. 2021;14:e244918.

Gelsomino M, Liotti L, Barni S. Elimination diets in lactating mothers of infants with food allergy. Nutrients. 2024;16(2317):https:// doi.org/10.3390/nu16142317.

Mennini M, fiocchi lG, Cafarotti A, Montesano M, Mauro A, Villa MP, et al. Food protein-induced allergic proctocolitis in infants: literature review and proposal of a management protocol. World Allergy Organization Journal. 2020;13:100471.

McWilliam V, Netting MJ, Volders E. World Allergy Organization (WAO) diagnosis and rationale for action against cow's milk allergy (DRACMA) guidelines update - X - Breastfeeding a baby with cow's milk allergy. World Allergy Organization Journal. 2023;16:100830.

Miceli Sop S, Monaco S, Bersani G. Proposal for management of the infant with suspected food protein-induced allergic proctocolitis. Paedatric Allergy and Immunology. 2018;29(2):215-218.

Silvatore S, Folegatti A, Ferrigno C. To diet or not to diet this is the question in food-protein-induced allergic proctocolitis (FPIAP) - a comprehensive review of current recommendations. Nutrients. 2024;16:589.

Tran K, Wisner E, Jeha G, Wall L. Development of IgE-mediated food allergies in children with history of food protein-induced allergic proctocolitis: a series of five cases. Frontiers in Allergy. 2024;5:1354106.

Vandenplas Y, Broekaert I, Domellof M. An ESPGHAN position paper on the diagnosis, management and prevention of cow's milk allergy. Journal of Pediatric Gastroenterology and Nutrition. 2024;78(2):386-413.

Wurm P, Stampfer L, Greimel T. Gut microbiota dysbiosis in suspected food protein induced proctocolitis - a prospective comparative cohort trial. Gastroenterology. 2023;77(1):31-38.