Babies born by C-section have different gut bacteria

Babies born by caesarean section have a reduced level of "good" gut bacteria and an increased number of pathogens linked to hospital environments, according to research co-led by UCL that is the most comprehensive study of the baby microbiome to date. In the study researchers analysed gut bacteria in stool samples taken from 596 babies born in British hospitals - 314 babies who had a natural, or vaginal, birth, and 282 who were born by caesarean. They took samples four, seven and 21 days after birth and later in infancy and also analysed samples from 175 mothers to determine the origin of the gut bacteria. The samples were gathered as part of the Baby Biome Study, co-led by Dr Nigel Field (UCL Institute for Global Health). Researchers concluded that babies born by C-section had a reduced number of "good" Bacteroides derived from their mothers and an increased number of opportunistic pathogens, including  Enterococcus,   Enterobacter and  Klebsiella species. The study provides evidence that the first colonisation of a newborn's intestine with bacteria varies with different birth methods. Researchers concluded that the type of birth is a significant risk factor in how the gut microbiome from newborns to infancy will be composed.