SUBSETS OF HUMAN RESIDENT BACTERIAL SPECIES THAT DIFFERENTIALLY STIMULATE IL-10 AND IFN gamma AND PROTECT VS. INDUCE COLITIS VARIABLY METABOLIZE TAURINE-CONJUGATED BILE ACIDS AND ACTIVATE BILE ACID-MEDIATED HOMEOSTATIC PATHWAYS

130.8 (102.3-147.3) vs. 3 rd trimester 84.9 (44.5-125.4),p=0.02) (Fig 1).Patients with flare at stool collection had the highest, while those treated with anti-tumor necrosis factor (TNF) plus thiopurine showed the lowest FC at each trimester.Babies born to mothers with IBD presented higher FC levels than those born to control mothers at multiple time points between 2 and 36 months of age (Fig 2A ); the median FC levels were the highest after 1 year up to 3 years in those babies whose mothers presented active disease during pregnancy (Fig 2B).Microbial a-diversity showed an inverse relationship with FC in both mothers (r=-0.25,p=0.032) and babies (r=-0.31,p=0.0035).Blautia and Streptococcus abundance were positively correlated with FC in babies.Conclusions: FC levels in IBD patients decreased throughout pregnancy.Maternal IBD, lower microbiome diversity and the abundance of certain microbial genera were associated with higher FC in the offspring up to 3 years of life.These findings suggest a potential favorable impact of pregnancy on IBD activity and highlight a possible effect of IBD during pregnancy on the intestinal inflammation in offspring, which could be mediated through altered microbiome.