Analysis of Fecal Short-Chain Fatty Acids (SCFAs) in Healthy Children during the First Two Years of Life: An Observational Prospective Cohort Study.

Short-chain fatty acids (SCFAs) are important metabolites of the gut microbiota. The aim is to analyze the influence of perinatal factors, which can affect the gut microbiota, on the concentrations of fecal SCFAs over the first two years of life. Gas chromatography was used to analyze SCFA in a total of 456 fecal samples from 86 children. Total SCFA concentrations increased until 12 months and stabilized after that. Antibiotic treatment during pregnancy was associated with an increase in acetic acid, propionic acid and total SCFA in meconium and a decrease in the same SCFAs at 6 months. Butyric acid was increased after Caesarean delivery until 1 month. In formula-fed children, propionic acid (at 1 month) and butyric acid and total SCFA (at 12 months) were increased. Acetic and linear butyric acids and total SCFAs were also increased at 12 months in children born vaginally that were also formula-fed. Higher butyric acid was observed in children of mothers with normal pre-pregnancy weight and adequate weight gain during pregnancy. Butyric acid was also elevated in 6-month-old infants with a higher body weight (≥85th percentile). Acetic acid concentrations were significantly higher in 2-year-old females vs. males. We conclude that perinatal factors are linked to changes in fecal SCFAs and further long-term epidemiological studies are warranted.