Probiotics
Other supplementAlso called · 3 names▾▴
probiotic, probiotic supplement, live microorganisms
Probiotic supplement
Herbs and supplements are not FDA-approved before sale. About these sources
- Other
Research strength: 3 / 5
NIH ODS says probiotic effects depend on the strain and not every product labeled as a probiotic has evidence of a health benefit. Cochrane's 2021 review reported higher risk of preeclampsia, a high blood pressure condition in pregnancy, while a 2024 review found no clear difference. A 2025 review of earlier reviews also reported higher risk, but it pooled estimates that may include some of the same studies. A 2019 trial of one two-strain product in women with overweight or obesity did not prevent gestational diabetes, and its preeclampsia difference was not statistically clear. Studies do not establish effects for every strain or for the first trimester. Ask your provider about your situation.
Last reviewed: 2026-10-15
Sources
- NIH Office of Dietary Supplements (ODS): Probiotics fact sheetUS government
- Cochrane: Probiotics for preventing gestational diabetesUS government
- McDougall et al. (2024): Probiotics and preeclampsia outcomesUS government
- Gao et al. (2025): Pregnancy-complications umbrella meta-analysisUS government
- Callaway et al. (2019): SPRING randomized trialUS government
Research strength: 3 / 5
NIH ODS says probiotic effects depend on the strain and not every product labeled as a probiotic has evidence of a health benefit. Cochrane's 2021 review reported higher risk of preeclampsia, a high blood pressure condition in pregnancy, while a 2024 review found no clear difference. A 2025 review of earlier reviews also reported higher risk, but it pooled estimates that may include some of the same studies. A 2019 trial of one two-strain product in women with overweight or obesity did not prevent gestational diabetes, and its preeclampsia difference was not statistically clear. Studies do not establish effects for every strain or for the second trimester. Ask your provider about your situation.
Last reviewed: 2026-10-15
Sources
- NIH Office of Dietary Supplements (ODS): Probiotics fact sheetUS government
- Cochrane: Probiotics for preventing gestational diabetesUS government
- McDougall et al. (2024): Probiotics and preeclampsia outcomesUS government
- Gao et al. (2025): Pregnancy-complications umbrella meta-analysisUS government
- Callaway et al. (2019): SPRING randomized trialUS government
Research strength: 3 / 5
NIH ODS says probiotic effects depend on the strain and not every product labeled as a probiotic has evidence of a health benefit. Cochrane's 2021 review reported higher risk of preeclampsia, a high blood pressure condition in pregnancy, while a 2024 review found no clear difference. A 2025 review of earlier reviews also reported higher risk, but it pooled estimates that may include some of the same studies. A 2019 trial of one two-strain product in women with overweight or obesity did not prevent gestational diabetes, and its preeclampsia difference was not statistically clear. Studies do not establish effects for every strain or for the third trimester. Ask your provider about your situation.
Last reviewed: 2026-10-15
Sources
- NIH Office of Dietary Supplements (ODS): Probiotics fact sheetUS government
- Cochrane: Probiotics for preventing gestational diabetesUS government
- McDougall et al. (2024): Probiotics and preeclampsia outcomesUS government
- Gao et al. (2025): Pregnancy-complications umbrella meta-analysisUS government
- Callaway et al. (2019): SPRING randomized trialUS government
Probiotics — Breastfeeding
Research strength: 3 / 5
NIH ODS reports mixed findings for infant eczema: one analysis found benefit only when exposure occurred before and after birth, while another found no benefit with LGG, including maternal use during pregnancy or breastfeeding. A randomized study of mothers taking one strain, HN001, from mid-pregnancy and, if breastfeeding, after birth did not significantly reduce infant eczema by 12 months; researchers did not detect HN001 in breast milk. An exploratory result from a 2025 trial of maternal supplementation, funded by a product maker, reported fewer days with infant infections but no statistically clear difference in how many infants were diagnosed. A 2026 review of prior studies judged evidence insufficient to confirm benefits or harms and rated significant associations as weak in credibility. These results do not establish effects for every strain or product. Ask your provider about your situation.
Last reviewed: 2026-10-15
Sources
- NIH Office of Dietary Supplements (ODS): Probiotics fact sheetUS government
- Wickens et al. (2018): Maternal-only HN001 randomized trialUS government
- Binda et al. (2025): Randomized trial of probiotics in pregnancy and infantsUS government
- Sun et al. (2026): Maternal probiotics and offspring health umbrella reviewUS government
Pregnancy
Human evidence is mixed and product-specific. Cochrane's 2021 review found uncertain effects on gestational diabetes and reported a preeclampsia increase, while McDougall et al. (2024) found no clear preeclampsia difference and rated that evidence low certainty. Gao et al. (2025) also reported increased preeclampsia and reduced gestational diabetes, but its umbrella analysis pooled estimates from earlier reviews and did not report adjustment for overlap among their primary studies. In the SPRING randomized trial, Callaway et al. (2019) studied 411 overweight or obese pregnant women receiving Lactobacillus rhamnosus plus Bifidobacterium animalis subsp. lactis or placebo; gestational diabetes occurred in 18.4% versus 12.3% (p=0.10), and preeclampsia in 9.2% versus 4.9% (p=0.09). The 2018 Cochrane review of maternal probiotic use for preterm-infant outcomes concluded that evidence was insufficient to determine appreciable neonatal benefit or harm. These sources do not establish one effect for all strains, doses, products, or trimesters.
Breastfeeding
Wickens et al. (2018) randomized 423 women to maternal-only Lactobacillus rhamnosus HN001 at 6 x 10^9 CFU daily or placebo, beginning at 14 to 16 weeks of pregnancy and continuing to 6 months postpartum if breastfeeding. HN001 did not significantly reduce infant eczema, wheeze, or atopic sensitization by 12 months, and it was not detected in breast milk. Binda et al. (2025) randomized 180 healthy pregnant women at 28 weeks to a specific product containing Lacticaseibacillus rhamnosus Rosell-11 and Bifidobacterium bifidum HA-132 or placebo; mothers continued the product for 4 to 6 weeks postpartum. The trial found fewer days with infant infections but no statistically clear difference in the number of infants diagnosed with infection; the maternal primary infection outcome also did not reach statistical significance. Lallemand Health Solutions funded the Binda trial, supplied the products, and employed or paid several authors. Sun et al. (2026) concluded that evidence on maternal supplementation and offspring health remains insufficient; the review rated statistically significant associations as weak in credibility. FDA's 2023 warning and the AAP caution concern probiotics administered directly to preterm infants in hospital settings, not maternal supplementation.
ODS describes probiotics as live microorganisms, mainly bacteria and sometimes yeasts. Products may contain one strain or several, and are identified by genus, species, and strain. Supplements are sold in forms such as capsules, powders, and liquids; some fermented foods also contain live microorganisms. ODS notes that products vary in strains, doses, and labeling, and that not every product labeled as a probiotic has evidence of a health benefit. There is no single ingredient or dose that represents all probiotics.
What was tested
Callaway et al. (2019) tested a daily oral combination of Lactobacillus rhamnosus and Bifidobacterium animalis subsp. lactis from before 20 weeks until birth in 411 pregnant women with overweight or obesity. Wickens et al. (2018) tested maternal-only HN001 at 6 x 10^9 CFU daily from 14 to 16 weeks of pregnancy through 6 months postpartum when breastfeeding in 423 women. Binda et al. (2025) tested 5 billion CFU per day of Lacticaseibacillus rhamnosus Rosell-11 and Bifidobacterium bifidum HA-132 from 28 weeks of pregnancy to 4 to 6 weeks postpartum in 180 healthy women. These trials do not represent every product or strain.
Preeclampsia in pregnancy trials
- Source A says
- Cochrane (2021) reported increased preeclampsia risk in pooled probiotic trials. (Davidson et al. (2021): Cochrane review, probiotics for preventing gestational diabetes)
- Source B says
- McDougall et al. (2024) found no clear difference in preeclampsia risk and rated the evidence low certainty. (McDougall et al. (2024): Systematic review and meta-analysis of probiotics and preeclampsia)
- Why they differ
- The reviews included different trial sets and combined studies that used varied strains, doses, populations, and intervention periods. Gao et al. (2025) pooled estimates from earlier reviews rather than a set of unique primary trials, and its full text does not report adjustment for overlap among those reviews.
- Other sources
- Gao et al. (2025) also reported a higher preeclampsia risk. In the 2019 SPRING trial, the preeclampsia difference between groups did not reach statistical significance. (Gao et al. (2025): Umbrella meta-analysis of probiotics and pregnancy complications, Callaway et al. (2019): SPRING randomized controlled trial)
- What the evidence shows overall
- The evidence does not establish that every probiotic product increases or prevents preeclampsia. The disagreement supports retaining guidance rather than changing the rating to avoid or compatible.
Maternal probiotic exposure and infant eczema
- Source A says
- ODS summarizes one analysis in which eczema findings differed by exposure timing and another analysis that found no benefit with LGG, including maternal exposure during pregnancy or breastfeeding. (NIH Office of Dietary Supplements (ODS): Probiotics fact sheet)
- Source B says
- Wickens et al. (2018) found that maternal-only HN001 did not significantly reduce infant eczema by 12 months. (Wickens et al. (2018): Maternal-only HN001 randomized trial)
- Why they differ
- The analyses used different probiotic strains, exposure schedules, and combinations of maternal and direct infant supplementation. A benefit seen when exposure spans pregnancy and infancy does not show a benefit from maternal supplementation alone.
- Other sources
- Sun et al. (2026) found that significant offspring associations had weak credibility and concluded that current evidence is insufficient to confirm benefits or harms. (Sun et al. (2026): Umbrella review of maternal probiotics and offspring health)
- What the evidence shows overall
- The evidence does not establish a general eczema benefit from maternal supplementation, and findings for one strain or timing schedule do not apply to every product.
Not enough research found yet.
General research, not specific to pregnancy.
ODS summarizes probiotic research for conditions outside pregnancy, but effects depend on the condition and strain. The FDA warning about direct use in hospitalized preterm infants is distinct from maternal supplementation.
- ODS reviews research on conditions including atopic dermatitis and antibiotic-associated diarrhea and notes that product effects vary by strain. (NIH Office of Dietary Supplements (ODS): Probiotics fact sheet)
- FDA's 2023 warning concerns probiotic products administered directly to preterm infants in hospital settings. AAP does not support routine direct administration in this vulnerable population, particularly infants with birth weight below 1,000 grams. A 2023 case report documented Bifidobacterium longum bacteremia in an extremely low birth weight infant and found that the strain likely came from the probiotic product. (FDA (2023): Probiotic products for hospitalized preterm infants, American Academy of Pediatrics (2021): Caution on probiotics in preterm infants, Acuna-Gonzalez et al. (2023): Bifidobacterium bacteremia case report in a preterm infant)
- NIH Office of Dietary Supplements (ODS): Probiotics fact sheetUS governmentSecondaryPage dated 2025-03-25
- Davidson et al. (2021): Cochrane review, probiotics for preventing gestational diabetesUS governmentPrimaryPage dated 2021-04-19Independent check
- McDougall et al. (2024): Systematic review and meta-analysis of probiotics and preeclampsiaUS governmentPrimaryPage dated 2024-03-04Independent check
- Gao et al. (2025): Umbrella meta-analysis of probiotics and pregnancy complicationsUS governmentPrimaryPage dated 2025-12-19Independent check
- Callaway et al. (2019): SPRING randomized controlled trialUS governmentPrimaryPage dated 2019-01-18Independent check
- Grev et al. (2018): Cochrane review of maternal probiotics and preterm-infant outcomesUS governmentPrimaryPage dated 2018-12-12Independent check
- Wickens et al. (2018): Maternal-only HN001 randomized trialUS governmentPrimaryPage dated 2018-04-06Independent check
- Binda et al. (2025): Randomized trial of probiotics in pregnancy and infantsUS governmentPrimaryPage dated 2025-05-28
- Sun et al. (2026): Umbrella review of maternal probiotics and offspring healthUS governmentPrimaryPage dated 2026-03-26Independent check
- FDA (2023): Probiotic products for hospitalized preterm infantsUS governmentSecondaryPage dated 2023-10-26
- American Academy of Pediatrics (2021): Caution on probiotics in preterm infantsSecondaryPage dated 2021-05-24Independent check
- Acuna-Gonzalez et al. (2023): Bifidobacterium bacteremia case report in a preterm infantUS governmentPrimaryPage dated 2023-02-06Independent check
Last reviewed 2026-10-15
Independent check 2026-10-15
Not yet clinician-reviewed
Ask your provider about your situation.
Related
- Prebiotics
- Synbiotics