The fetal gut starts off sterile and begins to populate with microorganisms after birth. About half of the microbial species in an infant’s gut within the first year come from the mother during childbirth and afterwards. Cesarean delivery may disrupt this process, as vaginal birth aids in the colonization of microorganisms in the infant’s gut.
Mothers undergoing cesarean delivery often receive antibiotics to prevent infections, which can also change the composition of their microbiome, reducing the bacteria available to colonize the infant’s gut.
Cesarean deliveries now make up over 25% of births worldwide. To counteract the effects on infant gut colonization, strategies like breastfeeding, skin-to-skin contact, and careful antibiotic use are recommended.
Research indicates that about half of the microbes in a newborn’s gut are not from maternal transmission alone. Other individuals around the infant may also contribute to its microbiome, but there’s still much to learn about which species they provide and their role in the infant gut.
Key Findings:
A recent study examined how the microbiota in infants born via vaginal or cesarean delivery is shared with both parents and changes in the first year of life.
Researchers analyzed data from 81 infants and 433 samples, including those from vaginal and cesarean deliveries, as well as from infants who received maternal fecal microbiota transplantation (FMT).
Changes in Infant Gut Microbiota:
Despite initial differences from adult gut microbiota, infants’ gut microbiota became more similar to their parents’ over time. The age of the infant and whether they received antibiotics during childbirth were the main factors influencing the gut microbiota, rather than the delivery mode.
By three weeks of age, infants received a significant amount of microorganisms from their mothers, decreasing over time. Contribution from the father was lower initially but remained steady over the first year.
FMT and Microbiota:
Infants who received FMT from their mothers showed significant differences in gut microbiota compared to those born via cesarean who didn’t receive FMT or vaginally. FMT increased bacterial growth in the infant gut and strain sharing with the mother, though it introduced species not usually found in infants.
Conclusion:
Fathers contribute significantly to the infant gut microbiota, reaching parity with mothers by one year regardless of delivery mode. Understanding the role of household members in microbiota development is crucial.
Antibiotics after birth can hinder bacterial growth rates and microbiota development. FMT shows promise in restoring disrupted seeding processes.
