Probiotics and Breastfeeding

Breastfeeding is already doing a great deal for your baby’s gut. Here is what a probiotic can honestly add, what it cannot, and the practical breastfeeding advice that changed in 2022 and is still catching up with the internet.

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If you are reading this at three in the morning with one hand, welcome. This article is written to be useful rather than flattering, which means some of it is going to say "we don’t know."

The good news first: breast milk is a genuinely remarkable thing, and most of what it does for your baby’s gut it does on its own. The rest of this is about where a probiotic might fit around that, and about the parts of breastfeeding advice that have quietly changed.

Two things to say up front. Nothing here is a reason to give a supplement to a baby — the FDA has approved no probiotic for use in infants of any age, and anything you give a baby should go past your pediatrician first.^8,9 And if you think you have mastitis, this article is not a substitute for calling someone.

What is actually in breast milk

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The headline act is a family of sugars called human milk oligosaccharides, or HMOs. They are the third most abundant solid component of human milk after lactose and fat — and here is the strange part: your baby cannot digest them. They are not food for the baby at all. They are food for the bacteria.¹

HMOs travel intact to the large intestine and feed particular bacteria — especially Bifidobacterium — which is why breastfed infants develop a gut community that looks quite different from anyone else’s. They also act as decoys, presenting sugar structures that pathogens bind to instead of binding to the baby’s gut wall.¹ A mother producing a liter of milk a day makes somewhere around 10 to 15 grams of these things purely for the benefit of her baby’s microbes.

The third most abundant solid in human milk is a sugar your baby cannot digest. It is there to feed the bacteria.

Breast milk also contains bacteria of its own, including Bifidobacterium and Lactobacillus, and those do appear to help seed the infant gut.² The honest caveat, from a 2026 review of the field: "direct evidence of specific strains establishing in the infant gut remains limited," partly because these are very low-biomass samples and contamination is a persistent methodological headache.²

Where the bacteria in milk come from is genuinely unsettled

You will read that bacteria travel from the mother’s gut to her breast — the "entero-mammary pathway." It is a real hypothesis with a real name, and the researcher who proposed it hedged carefully: certain gut bacteria "could" translocate, and "if such findings are confirmed in the future" it might be possible to influence infant health through the maternal gut.⁴ That was 2014, and confirmation has not arrived.

There is a strong competing explanation. When researchers compared the milk of mothers who nursed directly against those who pumped, the compositions differed — which "provides evidence for the retrograde mechanism of milk inoculation."³ In plain terms: some of the bacteria in breast milk may be traveling up from the baby’s mouth, not down from the mother’s gut. Current reviews treat the maternal gut, maternal skin, and the baby’s mouth as three plausible routes.²

This matters for the rest of the article, because the whole "supplement mom, benefit baby" story rests on that plumbing.

Your baby’s gut, and where a probiotic might fit

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The earlier version of this article said flatly that when a mother takes a probiotic, those organisms do not reach her breast milk. That turns out to be too strong — and it contradicted one of the article’s own cited sources, which is the sort of thing worth correcting properly.

That source, a systematic review of 29 trials, concluded: "The data available show that maternal probiotic supplementation during pregnancy or lactation results in probiotic colonization of the breastmilk microbiota."⁵ A later meta-analysis of 24 randomized trials covering 2,761 mothers found supplemented mothers were more likely to have beneficial bacteria detectable in their milk — a risk difference of 24% — though with very high variation between studies.⁶

So: yes, detectable, in some women, at low levels. Two caveats keep it honest. In one trial the administered strain turned up in colostrum in 12% of the supplemented group against 2% of placebo — a real difference, and a small one, and the trialists themselves suggested external contamination as a likely explanation.⁷ And the clinical protocol governing breast inflammation states that probiotics "have been shown not to alter composition of human milk microbiome."¹⁰ The field is not of one mind.

What about the next link in the chain — that a healthier maternal microbiome makes for healthier milk, which makes for a healthier baby? That is a reasonable-sounding idea and no trial has tested it end to end. Nobody has randomized mothers to a better microbiome, measured the resulting change in milk, and shown an infant health benefit traceable to that change. It is a hypothesis. This article is not going to promote it to a mechanism.

When the breast hurts: what changed in 2022

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This is the most useful section in the article, and none of it involves buying anything.

The story most of us learned is that mastitis happens when bacteria get in through a cracked nipple and milk sits still for too long. In 2022 the Academy of Breastfeeding Medicine replaced that model, and its protocol says so directly:

"New evidence about the composition of the human milk microbiome demonstrates that mastitis is not caused by retrograde spread of pathogenic bacteria from visible nipple trauma, as bacteria and fungi identified on the nipple-areolar-complex in the presence of nipple pain and damage are regularly identified in healthy human milk microbiomes."¹⁰

And on milk stasis: "Milk stasis has been postulated to be a potential instigating factor for mastitis, although scientific evidence has not proven a causation."¹⁰

The current model treats mastitis as a spectrum — ductal narrowing, then inflammatory mastitis, then bacterial mastitis, then in rarer cases phlegmon or abscess — driven by inflammation and by disruption of the milk’s own microbial community, with oversupply as a major contributor.¹⁰ It affects roughly one in ten breastfeeding women in the US, though published estimates vary widely depending on how mastitis is defined and how long women are followed.^11,12

A note on the "thrush in the ducts" diagnosis, which a lot of women are given: the protocol states that "despite the common perception that yeasts cause ‘candida mastitis,’ no scientific evidence exists to support this diagnosis."¹⁰

For balance, the 2022 protocol is not universally accepted. A published commentary argues it "inaccurately represents studies" and that advising reduced milk removal "may put breastfeeding women who present with breast inflammation at risk of worsened inflammation and decreased breast milk production."¹³ The spectrum model and the "don’ts" are now mainstream and echoed by US primary-care guidance;¹¹ hyperlactation as a diagnosis is where the argument is.

So — do probiotics help with mastitis?

Here is the whole picture, and it is more complicated than either side of the argument usually admits.

The Academy of Breastfeeding Medicine does list them, under "consider": "Data regarding probiotics are mixed. A systematic review suggested that probiotics may be effective for both treatment and prevention of mastitis, but a strong recommendation could not be made due to limitations of the studied trials." If used, it names two species — Limosilactobacillus fermentum or, preferably, Ligilactobacillus salivarius — and then adds the sentence that matters most: "Note that only selected strains of these bacterial species may be effective against mastitis pathogens. Therefore, clinical trial outcomes cannot be generalized to an entire species."¹⁰

The Cochrane review found that probiotics "may reduce the risk of mastitis more than placebo" (risk ratio 0.51), on low-certainty evidence from two trials and 399 women.¹⁴ A separate meta-analysis of six trials put the pooled reduction at a similar level while calling for "high-quality multicenter clinical trials."²⁰ Two things about that review deserve to be quoted rather than paraphrased. First: "Conflicts of interest on the part of trial authors, and the involvement of industry funders may also have had an impact on the certainty of the evidence." Second: "Results for the biggest of these trials (639 women) are currently unavailable due to a contractual agreement between the probiotics supplier and the trialists."¹⁴

That is worth sitting with. The largest trial ever run on this question has never been published, because the company supplying the product would not permit it. Meanwhile most of the published positive trials come from a single research group whose strains were commercialized.^15,16,17,18 There is even a paper in the literature titled "Probiotics and mastitis: evidence-based marketing?"¹⁹ — written about companies doing exactly what a probiotic company writing this section could be tempted to do.

And the most recent US clinical review is blunt: "Use of probiotics for treatment or prevention is not supported by good evidence."¹¹

Where that leaves it: specific strains may turn out to help, the evidence is low-certainty and commercially entangled, and no general-purpose probiotic can borrow those results. Flourish is not a treatment for mastitis and we are not going to suggest it is. If you think you have mastitis, ring your doctor, midwife or lactation consultant today.

What actually helps

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The protocol’s own summary of its approach is that these conditions "can be prevented and treated by reducing iatrogenic interventions and utilizing simple management principles such as ice, NSAIDs, and physiological breastfeeding."¹⁰ Translated: doing less, more gently, with proper pain relief and skilled support.

Skilled support is the thing. A lactation consultant watching one feed will do more for a painful latch than anything you can buy. If pain is your main problem and it is not mastitis, there is a whole separate clinical protocol on persistent breastfeeding pain covering vasospasm, skin conditions, latch problems and tongue tie — all treatable, all commonly mistaken for something else.²²

Rest, pain relief, and getting assessed quickly when something changes are unglamorous and better evidenced than anything on a shelf.

Eczema and allergy: what the evidence actually shows

This is where the older version of the article said probiotics show "great potential in the prevention and treatment of eczema." The treatment half needs to go, and the prevention half needs numbers.

The story starts well. A 2001 Finnish trial gave Lactobacillus rhamnosus GG to mothers before birth and then to their infants for six months. Eczema at two years: 23% versus 46%.²³ At four years the difference held.²⁴ A companion trial in 62 mother–infant pairs, supplementing through pregnancy and breastfeeding, found eczema at two years of 15% versus 47%.²⁵ That last one is the study the original article cited — note it spans pregnancy as well as lactation, so it cannot support breastfeeding-only supplementation on its own.

Then a German group ran the same strain, same design, 105 mother–infant pairs, and found nothing: atopic dermatitis 28% versus 27.3%. Their paper also reported more recurrent wheezing bronchitis in the supplemented children (26% versus 9.1%), and concluded that this strain "cannot be generally recommended for primary prevention."²⁶ Any article calling probiotics simply "safe" for this population ought to know that finding exists.

Where the guideline bodies have landed, twenty-five years on:

• World Allergy Organization (2015) — suggests probiotics in pregnant women at high risk of having an allergic child, and in women breastfeeding infants at high risk. But it opens by stating that "currently available evidence does not indicate that probiotic supplementation reduces the risk of developing allergy in children," and closes: "All recommendations are conditional and supported by very low quality evidence."²⁷
• EAACI (2021) — "There is no recommendation for or against… probiotics or synbiotics in pregnancy, when breastfeeding or in infancy."²⁸
• Cochrane (June 2025) — 24 studies, 7,077 mother–infant pairs. Probiotics "may result in a slight reduction in eczema by two years of age" (RR 0.87) on low-certainty evidence — but restricting to the trials at low risk of bias showed little or no difference (RR 0.86, CI 0.69–1.07). Its conclusion: "There is insufficient evidence to make conclusions about the effect of probiotics and synbiotics on preventing the development of allergic diseases."²⁹

On treating eczema, the answer is clearer and it is no. A Cochrane review of 39 trials and 2,599 participants found that probiotics "probably make little or no difference in participant- or parent-rated symptoms of eczema" — and that is moderate-certainty evidence for a null result, which is a stronger evidentiary position than the prevention claim ever had. Its conclusion: "use of probiotics for the treatment of eczema is currently not evidence-based."³⁰

One nuance from a 2026 meta-analysis that is genuinely interesting: infant-only supplementation has not shown consistent benefit, and what signal exists appears to come from perinatal regimens — mother plus infant, starting in pregnancy.³¹ Which is an argument for the maternal window, and an argument against dosing a baby.

Colic: the distinction that matters

The original article said maternal probiotic use may reduce crying in colicky babies. The evidence is real but it is about something else, and the difference is worth being precise about.

The best study is an individual-participant meta-analysis of four double-blind trials in 345 infants. The probiotic was Lactobacillus reuteri DSM 17938, and it was given directly to the babies, not to their mothers. Crying and fussing fell by about 25 minutes a day at three weeks, and the effect was "dramatic in breastfed infants… but… insignificant in formula-fed infants."³²

ESPGHAN’s 2023 position paper reflects that: for managing colic in breastfed infants it gives a weak recommendation, on moderate certainty, for L. reuteri DSM 17938 or B. lactis BB-12 — given to the infant. For preventing colic, no recommendation is possible. And it adds a line every probiotic company should read twice: "The use of probiotics with no documented health benefits should be discouraged."³³

There is some evidence that maternal supplementation is associated with less colic,⁶ but in most of those trials the infants were supplemented too, so the maternal contribution cannot be isolated. The honest version: the thing with good evidence is a specific strain given to the baby, and giving anything to a baby is a conversation with your pediatrician, not a purchase.⁹

After a cesarean

The original article said that taking a probiotic after a cesarean offers potential benefits for post-operative recovery. We looked for the evidence behind that and could not find any — there appear to be no trials of probiotics for maternal recovery after cesarean birth at all. The perioperative probiotic research that exists is in colorectal and abdominal surgery, which is a different operation in a different population. So that sentence is gone.

What is well supported is the part about breastfeeding, and it is more encouraging than the usual telling. The UK Baby Biome Study followed 596 full-term babies and found disrupted transmission of maternal bacteria and more hospital-associated organisms in cesarean-born infants — and then this: "These effects were also seen, to a lesser extent, in vaginally delivered babies whose mothers underwent antibiotic prophylaxis and in babies who were not breastfed during the neonatal period."³⁴

Read that last clause again. Not breastfeeding pushed in the same direction as cesarean birth. Which makes feeding your baby — however that is going for you — the lever you actually have. We have written separately about cesarean birth and the microbiome, including the reassuring part about how those differences narrow over the first year.

Is it safe to take a probiotic while breastfeeding?

For a healthy adult woman, no pattern of harm has emerged — and that is a more careful sentence than "it’s safe," deliberately.

The most-cited lactation-specific assessment is a 2011 clinical column which concluded: "Probiotics do not appear to pose any safety concerns for pregnant and lactating women. Systemic absorption is rare when probiotics are used by healthy individuals, and the current literature does not indicate an increase in adverse pregnancy outcomes."³⁵ It is fifteen years old and it is still the best there is. Worth knowing too: LactMed, the standard US reference for medications and breastfeeding, has no monograph on probiotics at all. If someone tells you LactMed says probiotics are safe in lactation, LactMed says nothing.

Cochrane’s 2025 infant review reported no serious adverse events related to probiotics.²⁹ Most trials in this literature were not designed to detect harms, which is a limitation rather than a reassurance.

Talk to your doctor first if you or your baby are in any of these groups:

• Any preterm or low-birthweight baby, or any baby with a central line⁸
• Anyone immunocompromised — chemotherapy, transplant, high-dose steroids, HIV with a low CD4 count³⁵
• Anyone critically ill, or with a compromised gut lining (short bowel, a severe IBD flare, recent bowel surgery)³⁵
• Anyone with a prosthetic heart valve or a history of endocarditis
• Any mother unwell enough to need intravenous antibiotics — that is a clinician’s job, not a supplement’s

The short version

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Breast milk is already doing the heavy lifting for your baby’s gut, largely through sugars your baby cannot even digest.¹ Probiotic organisms a mother takes can turn up in her milk at low levels, though the field disagrees about how much that matters and nobody has traced the chain from mother’s supplement to baby’s health.^5,6,10

For eczema prevention the guideline bodies range from a conditional suggestion on very low quality evidence to no recommendation at all.^27,28,29 For eczema treatment the answer is no.³⁰ For colic the evidence is about a specific strain given to the baby, which is a pediatrician conversation.^32,33 For mastitis the evidence is low-certainty, strain-specific and commercially compromised, and the practical advice — ice, ibuprofen, no deep massage, feed on demand, get seen quickly — is worth more than any supplement.^10,11,14

And the least fashionable finding in the whole literature is the most reliable one: what helps a struggling breastfeeding mother is skilled support, adequate pain relief, rest, and being taken seriously when something is wrong.

A note about Flourish

Flourish is a living liquid probiotic taken daily by adults for general digestive and microbiome support — eleven species from five genera, fermented together as one culture, made in small batches in the USA, and third-party lab tested every batch for potency, purity and the absence of harmful bacteria and common allergens.

What it is not, stated plainly, because this is an article about mothers and babies:

• It is not a treatment for mastitis, and the strain-specific evidence discussed above does not transfer to it.¹⁰
• It is not a treatment or a preventive for eczema or allergy.^29,30
• It is not for your baby. No probiotic is FDA-approved for infants of any age. Talk to your pediatrician before giving a baby anything.⁹

If you are pregnant, breastfeeding, or taking any medication, check with your provider before starting it — the same thing we would say about any supplement, including this one.

Flourish is a dietary supplement intended to support digestive and microbiome health. It is not a treatment for mastitis, eczema, colic, or any other condition, and it is not intended for infants. Speak to your healthcare provider before starting any supplement while pregnant or breastfeeding, and speak to your pediatrician before giving anything to a child. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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A few questions we hear a lot

Can I take a probiotic while breastfeeding?

For a healthy adult, no pattern of harm has shown up in the research, and the standard lactation reference has no entry on probiotics either way.³⁵ Check with your provider first, particularly if you are immunocompromised or unwell.

Will it get into my breast milk?

Sometimes, at low levels. Systematic reviews find supplemented mothers are more likely to have those organisms detectable in milk,^5,6 while the breastfeeding-medicine protocol states probiotics have been shown not to alter the milk microbiome.¹⁰ Both statements are in the literature. What nobody has shown is that any of it changes a baby’s health.

I think I have mastitis. What do I do right now?

Call your doctor, midwife or IBCLC today. In the meantime: ice rather than heat, ibuprofen if you can take it, feed on demand, and do not deep-massage the breast — that makes it worse.¹⁰ Go in urgently for fever, spreading redness, a firm lump, or no improvement in 24 to 48 hours.

Should I stop breastfeeding if I have mastitis?

No. "Bacterial mastitis is not a contagious entity and does not pose a risk to the infant nor require an interruption in breastfeeding."¹⁰

Will taking a probiotic stop my baby getting eczema?

Nobody can promise that. The World Allergy Organization made a conditional suggestion for high-risk families in 2015 on very low quality evidence; EAACI makes no recommendation either way; and a 2025 Cochrane review found the evidence insufficient.^27,28,29 It is a reasonable thing to discuss with your provider if allergy runs in your family, and not something to count on.

Can I give my baby a probiotic for colic?

Ask your pediatrician before you buy anything. The evidence is for one specific strain given directly to breastfed infants,^32,33 and the FDA has approved no probiotic for infants of any age.⁹

I had a cesarean. Should I take a probiotic to help recovery?

There is no evidence for that — we looked. What does help your baby’s microbiome after a cesarean is breastfeeding, in whatever amount is working for you.³⁴

Important information

This article is for general education and is not a substitute for professional medical advice, diagnosis, or treatment. If you are unwell, in increasing pain, or worried about your breast or your baby, contact your healthcare provider the same day. Guideline and protocol recommendations are summarized here in brief; the linked documents contain the full wording and the certainty of the underlying evidence. Probiotic effects are specific to the strain, the dose and the population studied, and evidence for one product does not transfer to another. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Sources

1. Bode, L. (2012). Human milk oligosaccharides: every baby needs a sugar mama. Glycobiology, 22(9), 1147–1162. Source
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3. Moossavi, S., & Azad, M. B. (2020). Origins of human milk microbiota: new evidence and arising questions. Gut Microbes, 12(1), 1667722. Source
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5. Zaidi, A. Z., Moore, S. E., & Okala, S. G. (2021). Impact of maternal nutritional supplementation during pregnancy and lactation on the infant gut or breastmilk microbiota: a systematic review. Nutrients, 13(4), 1137 — 29 randomized trials. Source
6. Alemu, B. K., Azeze, G. G., Wu, L., Lau, S. L., Wang, C. C., & Wang, Y. (2023). Effects of maternal probiotic supplementation on breast milk microbiome and infant gut microbiome and health: a systematic review and meta-analysis of randomized controlled trials. American Journal of Obstetrics & Gynecology MFM, 5(11), 101148 — 24 RCTs; heterogeneity was very high. Source
7. Abrahamsson, T. R., Sinkiewicz, G., Jakobsson, T., Fredrikson, M., & Björkstén, B. (2009). Probiotic lactobacilli in breast milk and infant stool in relation to oral intake during the first year of life. Journal of Pediatric Gastroenterology and Nutrition, 49(3), 349–354. Source
8. U.S. Food and Drug Administration (29 September 2023). Letter to health care providers: warning regarding use of probiotics in preterm infants. Source
9. U.S. Food and Drug Administration (26 October 2023). FDA raises concerns about probiotic products sold for use in hospitalized preterm infants — "the FDA has not approved any probiotic product for use as a drug or biological product in infants of any age." Source
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11. Morcomb, E. F., Dargel, C. M., & Anderson, S. A. (2024). Mastitis: rapid evidence review. American Family Physician, 110(2), 174–182. Source
12. Wilson, E., Woodd, S. L., & Benova, L. (2020). Incidence of and risk factors for lactational mastitis: a systematic review. Journal of Human Lactation, 36(4), 673–686 — the authors note "a critical lack of high quality epidemiological evidence." Source
13. Douglas, P. (2023). Does the Academy of Breastfeeding Medicine’s Clinical Protocol #36 "The Mastitis Spectrum" promote overtreatment and risk worsened outcomes for breastfeeding families? Commentary. International Breastfeeding Journal, 18(1), 51. Source
14. Crepinsek, M. A., Taylor, E. A., Michener, K., & Stewart, F. (2020). Interventions for preventing mastitis after childbirth. Cochrane Database of Systematic Reviews, 9(9), CD007239. Source
15. Jiménez, E., Fernández, L., Maldonado, A., Martín, R., Olivares, M., Xaus, J., & Rodríguez, J. M. (2008). Oral administration of Lactobacillus strains isolated from breast milk as an alternative for the treatment of infectious mastitis during lactation. Applied and Environmental Microbiology, 74(15), 4650–4655 — n=20; two authors were employed by the company that commercialized the strains. Source
16. Arroyo, R., Martín, V., Maldonado, A., Jiménez, E., Fernández, L., & Rodríguez, J. M. (2010). Treatment of infectious mastitis during lactation: antibiotics versus oral administration of lactobacilli isolated from breast milk. Clinical Infectious Diseases, 50(12), 1551–1558 — n=352, open-label, no placebo arm. Source
17. Fernández, L., Cárdenas, N., Arroyo, R., et al. (2016). Prevention of infectious mastitis by oral administration of Lactobacillus salivarius PS2 during late pregnancy. Clinical Infectious Diseases, 62(5), 568–573. Source
18. Hurtado, J. A., Maldonado-Lobón, J. A., Díaz-Ropero, M. P., et al. (2017). Oral administration to nursing women of Lactobacillus fermentum CECT5716 prevents lactational mastitis development: a randomized controlled trial. Breastfeeding Medicine, 12(4), 202–209 — four of eleven authors were employed by the strain’s manufacturer. Source
19. Amir, L. H., Griffin, L., Cullinane, M., & Garland, S. M. (2016). Probiotics and mastitis: evidence-based marketing? International Breastfeeding Journal, 11, 19. Source
20. Yu, Q., Xu, C., Wang, M., et al. (2022). The preventive and therapeutic effects of probiotics on mastitis: a systematic review and meta-analysis. PLOS ONE, 17(9), e0274467 — the authors call for high-quality multicentre trials. Source
21. Louis-Jacques, A. F., Berwick, M., & Mitchell, K. B. (2023). Risk factors, symptoms, and treatment of lactational mastitis. JAMA, 329(7), 588–589. Source
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23. Kalliomäki, M., Salminen, S., Arvilommi, H., Kero, P., Koskinen, P., & Isolauri, E. (2001). Probiotics in primary prevention of atopic disease: a randomised placebo-controlled trial. The Lancet, 357(9262), 1076–1079. Source
24. Kalliomäki, M., Salminen, S., Poussa, T., Arvilommi, H., & Isolauri, E. (2003). Probiotics and prevention of atopic disease: 4-year follow-up of a randomised placebo-controlled trial. The Lancet, 361(9372), 1869–1871. Source
25. Rautava, S., Kalliomäki, M., & Isolauri, E. (2002). Probiotics during pregnancy and breast-feeding might confer immunomodulatory protection against atopic disease in the infant. Journal of Allergy and Clinical Immunology, 109(1), 119–121 — n=62 mother–infant pairs; supplementation spanned pregnancy and lactation. Source
26. Kopp, M. V., Hennemuth, I., Heinzmann, A., & Urbanek, R. (2008). Randomized, double-blind, placebo-controlled trial of probiotics for primary prevention: no clinical effects of Lactobacillus GG supplementation. Pediatrics, 121(4), e850–e856. Source
27. Fiocchi, A., Pawankar, R., Cuello-Garcia, C., et al. (2015). World Allergy Organization–McMaster University guidelines for allergic disease prevention (GLAD-P): probiotics. World Allergy Organization Journal, 8(1), 4. Source
28. Halken, S., Muraro, A., de Silva, D., et al. (2021). EAACI guideline: preventing the development of food allergy in infants and young children (2020 update). Pediatric Allergy and Immunology, 32(5), 843–858. Source
29. Wang, H. Z., Hayles, E. H., Fiander, M., Sinn, J. K., & Osborn, D. A. (2025). Probiotics in infants for prevention of allergic disease. Cochrane Database of Systematic Reviews, 6(6), CD006475 — 24 studies, 7,077 mother–infant pairs. Source
30. Makrgeorgou, A., Leonardi-Bee, J., Bath-Hextall, F. J., et al. (2018). Probiotics for treating eczema. Cochrane Database of Systematic Reviews, 11(11), CD006135 — 39 trials, 2,599 participants. Source
31. Wei, T., & Ding, Y. (2026). Efficacy of probiotics in preventing atopic dermatitis in infants: a systematic review and meta-analysis. Journal of International Medical Research, 54(7) — 18 RCTs, 10,195 participants. Source
32. Sung, V., D’Amico, F., Cabana, M. D., et al. (2018). Lactobacillus reuteri to treat infant colic: a meta-analysis. Pediatrics, 141(1), e20171811 — individual-participant meta-analysis of 4 trials, 345 infants, probiotic given to the infants. Source
33. Szajewska, H., Berni Canani, R., Domellöf, M., et al. (2023). Probiotics for the management of pediatric gastrointestinal disorders: position paper of the ESPGHAN Special Interest Group on Gut Microbiota and Modifications. Journal of Pediatric Gastroenterology and Nutrition, 76(2), 232–247. Source
34. Shao, Y., Forster, S. C., Tsaliki, E., et al. (2019). Stunted microbiota and opportunistic pathogen colonization in caesarean-section birth. Nature, 574(7776), 117–121 — the UK Baby Biome Study; 596 full-term babies. Source
35. Elias, J., Bozzo, P., & Einarson, A. (2011). Are probiotics safe for use during pregnancy and lactation? Canadian Family Physician, 57(3), 299–301 — a Motherisk clinical column, retained from the original article’s source list. Source

The original version of this article also cited a consumer article, "Can Breastfeeding Women Take Probiotics?", published by Verywell Family. That publication was discontinued and the article is no longer available, so it could not be checked or linked. No statement above relies on it.