The helpful bacteria that colonize a newborn’s intestines come not just from the baby’s mother but from its father as well, according to a new study.
Babies’ bodies are colonized by bacteria during and shortly after birth. About half of the strains found in infants’ bodies are known to have come from the mother’s gut.
“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,” study leader Willem M. de Vos, of the University of Helsinki said in a statement.
The researchers analyzed the assortment of organisms, known as the microbiome, in fecal samples collected over time from 73 infants, including 21 born by caesarian section and 52 born vaginally.
Many of the strains found in the babies at 3 weeks, 3 months, and 12 months originated in their fathers, not in their mothers, the researchers discovered.
“We found little overlap between the strains acquired from the two parents, suggesting complementary contributions to shaping the infant microbiota in early life,” the researchers wrote in Cell Host & Microbe.
The father’s contribution may be particularly important after cesarean deliveries, because antibiotics administered to the mother after the procedure to prevent surgery-related infections may disrupt her own gut bacteria and affect transmission of those organisms to her baby, the researchers noted.
“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 co-author Nicola Segata of the University of Trento in Italy.
Other microbial contributions may come from siblings and from daycare peers, the researchers also said.
