Fathers' Influence on Newborn Gut Microbiota

The maternal influence on the infant gut microbiota is well established. However, a recent study, published in Cell Press, indicates that fathers also play a role in shaping the microbial composition of a newborn’s gut. The paper also investigated the use of maternal fecal microbiota transplantation (FMT) in aiding colonization in babies born via cesarean section (c-section).

Fetuses are sterile in the womb

Before labor begins, it is widely believed infants are sterile, and rapid colonization of microbes begins during and after birth. Establishing a healthy gut composition early is essential for short- and long-term health in babies.

Previous studies have identified the mother as the main contributor of these species, and around half of the strains found in an infant can be traced back to the maternal microbiota. How the remaining half of the strains colonize the infant gut is not yet fully understood, causing researchers to look at other family members who have close contact with the child.

Microbial colonization can be disrupted by several factors, such as birth delivery route. Infants born via c-section have been shown to contain a higher percentage of pathogenic bacteria in their gut compared to those born naturally. Understanding how the infant gut microbiota is established is vital to improving neonatal care.

Continue reading below...

Article

Do Cesarean-Born Babies “Miss Out” on Essential Microbes?

Read more

Fathers contribute to the infant gut microbiota

The research provided follow-up data to their proof-of-concept study, published in 2020, which investigated the use of maternal FMT in cesarean-born infants. A metagenomic analysis was performed on the fecal samples from 73 infants, consisting of 21 born via c-section and 52 born vaginally, and their parents. Samples were collected over a year and compared to the microbiota of their mothers and fathers.

Many of the strains identified at week 3, month 3 and after 12 months originated from the father’s microbiota including Bifidobacterium longum strains.

B. longum is important for digesting breast milk in the infant gut, however, the results suggest these strains may be originating from the paternal microbiota.

The infants included in the previous 2020 study underwent additional follow-up analysis to confirm the results from the maternal FMT. The researchers confirmed the procedure significantly reduced the levels of potential pathogenic bacterial strains for up to one year.

Increasing our understanding of neonatal health

“The role of the father may be small, but it is not to be neglected. It is likely that the same holds for others who have close contact with the newborn,” said lead author Dr. Willem M. de Vos, professor at Wageningen University and the University of Helsinki.

“We are very happy to have found this connection,” explained co-author Dr. Nicola Segata, professor and principal investigator from the CIBIO Department at the University of Trento. “This highlights the importance of studying other microbial contributions as well, such as those from siblings and from daycare peers."

Considering c-section deliveries account for one-quarter of births worldwide, understanding how newborns are colonized and ways to achieve a stable microbiota are vital for neonatal health.

“Knowing that the father substantially contributes to a baby’s developing microbiome underlies the important role of physical and social interactions between the newborn and their father, as well as with other family members,” said Segata. “We hope this study will help to create awareness of those important contributions."

Researchers from the University of Helsinki have completed another follow-up maternal FMT trial, investigating not only the microbiome but also other health and immune functions.

Reference: Dubois L, Valles-Colomer M, Ponsero A, et al. Paternal and induced gut microbiota seeding complement mother-to-infant transmission. Cell Host Microbe. 2024. doi: 10.1016/j.chom.2024.05.004

This article is a rework of a press release issued by Cell Press. Material has been edited for length and content.