Infant Delivery, Feeding Can Affect Gut Bacteria
Study shows vaginal birth and breast-feeding create different intestinal bacteria from C-section and formula
By Alan Mozes
MONDAY, Jan. 11, 2016 (HealthDay News) -- A vaginal birth and breast-feeding make a notable difference in the bacterial composition of an infant's gut, according to new research.
At issue is the gastrointestinal makeup of the microbiome, the collection of microbes mainly in the large intestine that are essential to the immune system and good nutrition.
By tracking the birth and feeding records of more than 100 infants who were only 6 weeks old, investigators found that those born vaginally had a different gut composition from those delivered by cesarean section.
Differences were also seen between babies exclusively breast-fed compared with those fed with either formula or a mixture of formula and breast milk.
However, it was not clear whether such differences affect a baby's short-term or long-term health, study co-author Anne Gatewood Hoen said.
"Our study doesn't establish links with health outcomes at this time," said Hoen, an assistant professor of epidemiology and of biomedical data science with the Geisel School of Medicine at Dartmouth College in Lebanon, N.H.
But Hoen and lead author Dr. Juliette Madan, a neonatologist and assistant professor of pediatrics at Geisel/Dartmouth, noted that their team was "surprised to find that even at six weeks following birth, the gut microbiome seems to be shaped by delivery mode as much as it is by feeding method.
"This suggests that the major encounter with bacterial life that occurs during the process of birth is very important in the establishment of the gut microbiome and that its effects are lasting," the researchers said.
The authors noted in the study that "cesarean delivery has been associated with an increased risk for obesity, asthma, celiac disease and type 1 diabetes mellitus," and, compared to formula feeding, "breast-feeding has been related to decreased risks for illnesses such as asthma, obesity, infection, metabolic syndrome and diabetes."
Hoen and Madan outlined their findings in the Jan. 11 online edition of JAMA Pediatrics.
Roughly two-thirds of the infants in the study had been born vaginally, with the remaining third delivered via C-section. Similarly, about two-thirds had been exclusively fed breast milk in the first six weeks of life, while 26 were fed with a combination of breast milk and formula. Six were fed only formula.