Cesarean section {51111212}

Shared Reference Notes

• [1.1] 
  - C-section was associated with lower microbial diversity at four months, and the abundance of 25 types of bacteria differed in kids born with C-section. - The effect of c-section on gut microbiota is normalized in 3–5-year-old children
• [1.2] [#Pregnancy] [#Vaginally delivery] 
• [1.3] 
  - babies who are delivered by Cesarean section (C-section) are often colonized by bacteria that are more commonly found on the skin, including #Staphylococcus, #Propionibacterium or #Corynebacterium
• [1.4] [#Vaginally delivery] 
  - #Bacteroides indeed disappears around week 1 of life in CS-born infants after initial colonization, whereas colonization persists in those vaginally born.
• [#Human breast milk, #Mother-infant] - In CS-born infants > reduced seeding of infant fecal microbiota by maternal fecal microbes, whereas colonization with breastmilk microbiota is increased when compared with vaginally born infants. - auxiliary routes of mother-to-infant microbial seeding, which may compensate for one another, ensuring that essential microbes/microbial functions are transferred irrespective of disrupted transmission routes.
• [1.5] [#Short Chain Fatty Acid] 
  - #Children born by C-section exhibit an overall reduced gut microbiome stability and reduced stool levels of SCFAs (especially #Acetate) during the first months of life as well as a delayed maturation of the gut microbiome by the second year of life.
• [#Acute lymphoblastic leukemia] [#Bacteroides ovatus, #Bacteroides uniformis, #Bacteroides vulgatus] - #Children with ALL at the time of diagnosis were reported to have reduced relative abundance of B. vulgatus, B. ovatus and B. uniformis; that is, immunomodulatory bacterial species whose transmission from mother to child is disrupted by C-section
• [#Acute lymphoblastic leukemia] - Elective C-section, an established risk factor for BCP-ALL induces persisting compositional and functional instability in the gut microbiome (especially in #Bacteroides spp.) > suppress Treg cell differentiation and compromise gut immune tolerance, leading to the promotion of pro-inflammatory responses.
• [#Acute lymphoblastic leukemia] [#Cessation of breastfeeding, #Human breast milk, #Socio-economic status] - The risk of BCP-ALL is increased by caesarean section (C-section) birth, brief or absent breastfeeding and paucity of social contacts during infancy. - these social risk factors are shared with type 1 diabetes and allergies, raising the possibility of a common underlying immune priming deficit.
• - #Children born by C-section demonstrate reduced colonization stability of #Bacteroides by day 14 and reduced abundance throughout infancy and up to 5 years of life. - The low-#Bacteroides profile of neonates delivered by C-section is accompanied by an increased relative abundance of opportunistic pathogens (for example, #Enterococcus spp. and #Klebsiella spp.)
• [1.6] [#Human breast milk, #Vaginally delivery] 
  - At 6 weeks postpartum, the composition and structure of gut microbiota of cesarean section-delivered (CSD) #Infants differed from those of vaginally delivered (VD) #Infants, with decreased #Bacteroides and #Escherichia-#Shigella and increased #Klebsiella, #Veillonella, and #Enterococcus. - At 6 months postpartum, these delivery mode-induced microbial shifts were restored by exclusive breastfeeding, resulting in similar gut microbial profiles between VD and CSD #Infants who were exclusively breastfed and more variable gut microbial profiles between VD and CSD #Infants who were mixed fed.
• [1.7] [#Vaginal Microbiome Transfer] 
  - #Vaginal microbiota transfer (VMT) to newborns may reverse C-section-related microbiome disturbances
• [1.8] [#Colorectal cancer] 
  - birth by cesarean delivery was not associated with early-onset CRC in the overall population

References Notes