Impact of maternal supplementation with probiotics during pregnancy on atopic eczema in childhood – a meta-analysis

Seven randomized, double-blind, placebo-controlled trials (2001–2009) with 2,843 children; mothers took probiotics during pregnancy and lactation; offspring assessed for atopic eczema between ages 2 and 7 years.

Oral probiotic regimens during pregnancy and lactation varied: Lactobacillus rhamnosus GG (5×10^9 CFU/day) with additional strains (LC705, Bb99, Propionibacterium freudenreichii ssp. Shermanii) and other regimens using L. rhamnosus HN001 (6×10^9 CFU/day) with Bifidobacterium animalis ssp. lactis HN019 (9×10^9 CFU/day), or Lactobacillus reuteri (1×10^8 CFU/day). Durations ranged from ~36 weeks of gestation to 6–24 months postnatally; all regimens administered orally.

Probiotic intake during pregnancy reduces offspring risk of atopic eczema in childhood. Overall risk reduction 5.7% (P=0.022). Reduction strongest for lactobacilli (10.6%, P=0.045); no significant reduction with a mixture of strains (3.06%, P=0.204). Lactobacilli-containing regimens during pregnancy and lactation may lower eczema risk by ages 2–7; mixtures do not show benefit. More longitudinal studies are needed to confirm long-term effects.

Variation in probiotic strains, dosages, and regimens across trials; some trials used multi-strain formulations; only a subset contributed to the significant overall effect; long-term outcomes remain uncertain.