High to moderate certainty in the body of evidence suggests that LGG supplementation ( regardless of the timing of administration ) did not reduce the risk of eczema .
There was also no consistent effect on other allergic outcomes .
This meta- analysis shows that LGG was ineffective in reducing eczema .
Current guidelines recommend the use of probiotics to reduce the risk of  eczema .
It remains unclear which strain(s ) to use .
We systematic ally evaluated data on the efficacy of Lactobacillus rhamnosus GG ( LGG ) supplementation prenatally and /or postnatally for the primary prevention of eczema .
Probiotics and prevention of atopic disease: 4-year follow-up of a randomised placebo-controlled trial
Perinatal administration of the probiotic Lactobacillus rhamnosus strain GG ( ATCC 53103 ) , reduces incidence of atopic eczema in at-risk children during the first 2 years of life ( infancy ) . We have therefore assessed persistence of the potential to prevent atopic eczema at 4 years . Atopic disease was diagnosed on the basis of a question naire and a clinical examination . 14 of 53 children receiving lactobacillus had developed atopic eczema , compared with 25 of 54 receiving placebo  ( relative risk 0.57 , 95 % CI 0.33 - 0.97 ) . Skin prick test reactivity was the same in both groups : ten of 50 children previously given lactobacillus compared with nine of 50 given placebo tested positive . Our results suggest that the preventive effect of lactobacillus GG on atopic eczema extends beyond infancy
High to moderate certainty in the body of evidence suggests that LGG supplementation ( regardless of the timing of administration ) did not reduce the risk of eczema .
There was also no consistent effect on other allergic outcomes .
This meta- analysis shows that LGG was ineffective in reducing eczema .
Current guidelines recommend the use of probiotics to reduce the risk of  eczema .
It remains unclear which strain(s ) to use .
We systematic ally evaluated data on the efficacy of Lactobacillus rhamnosus GG ( LGG ) supplementation prenatally and /or postnatally for the primary prevention of eczema .