Babies were less likely to get the itchy skin rash eczema when their mothers took probiotics during pregnancy and while breastfeeding, according to a study from Finland.
Researchers said it's possible that probiotics - which are thought to help balance bacteria populations in the gut and prevent disease-causing strains from spreading - may influence babies' health through immune cells that cross the placenta and later are passed in breast milk.
"Prevention regimen with specific probiotics administered to the pregnant and breast-feeding mother, that is, prenatally and postnatally, is safe and effective in reducing the risk of eczema in infants with allergic mothers," wrote lead author Samuli Rautava of Turku University Central Hospital, in the Journal of Allergy and Clinical Immunology.
For the study, Rautava and his colleagues assigned 241 pregnant women to take one of two different probiotic combinations, given as a powder mixed with water once daily, or a bacteria-free placebo powder.
All of the mothers-to-be had a history of allergies, so their babies were at extra-high risk of eczema and other allergic reactions.
The women drank their assigned concoction for the last two months of pregnancy and their first two months of breastfeeding. Researchers then tracked their babies' health for two years to see how many developed rashes.
By the end of the study, 71 percent of babies in the placebo group had had eczema at least once, compared to 29 percent of babies whose mother took either probiotic combination.
Chronic eczema was diagnosed in 26 percent of placebo kids, compared to 10 percent and six percent, respectively, of those in the two probiotic groups.
However, by age two there was no difference in kids' sensitivities to a range of allergens, including milk, wheat, soy and dog and cat dander, based on whether their mothers had taken the supplements. About one quarter of the children had a positive "skin prick" test for sensitivity to an allergen.
"(The study) really shows a reduction in eczema from probiotics, which is such a simple and easy intervention for mothers,' said Ruchi Gupta, an allergy an eczema researcher at the Northwestern University Feinberg School of Medicine.
But she said it was still too soon to see if that reduction in eczema will be tied to a drop in asthma and more serious allergies later on, and Rautava himself said it was still not yet possible to make recommendations for routine use of probiotics.
Rautava and his colleagues didn't find any evidence of probiotic-related side-effects, and while there have been reports of infections attributed to probiotics in babies, giving the supplements to the mothers instead may reduce that risk.
But some researchers questioned whether the supplements sold on drugstore shelves have any real health benefits, especially including all the different strains available.
"The results look encouraging, but this is a controversial area and confirmation is needed," said James Gem, a pediatric allergy researcher from the University of Wisconsin School of Medicine and Public Health.
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