FIGURE 3.

Impact of early-life antibiotics on composition of the gut microbiota from DM and MOM infants at the genus level. (A) Relative abundance of genera during the first week of life separated by diet and timing by which antibiotic-exposed infants’ stool samples were obtained (before, during, or after exposure to antibiotics). No stool samples in week 1 were obtained before the initiation of antibiotics. Sample sizes are small for this group because most premature infants did not have a stool sample of sufficient quantity during the first week of life. (B) Relative abundance of genera during the second week of life separated by diet and timing by which antibiotic-exposed infants’ stool samples were obtained (before, during, or after antibiotics). One infant receiving DM had a stool sample obtained in week 2 before initiation of antibiotics, and this patient's microbiota composition was similar to those obtained in week 2 from the 7 infants receiving DM who never received antibiotics. DM, donor human milk; MOM, mother's own milk.