Background: The rate of caesarean deliveries has increased 10-fold worldwide during the past decades. Objective: To evaluate differences in the establishment of gut microbiota in infants born by vaginal or caesarean delivery and its impact on mucosal immunity. Methods: Altogether, 165 consecutive children, prospectively followed from birth at our clinic in Turku, Finland, were gathered; 141 (85%) were born by vaginal delivery and 24 (15%) by caesarean section. Blood was drawn at physician visits for indirect evaluation of mucosal immunity by ELISPOT assay. Faecal samples were obtained for determination of the gut microbiota by fluorescence in situ hybridization of bacterial cells. Results: Infants delivered by caesarean section harboured fewer bifidobacteria at an early age and were shown to mount a stronger humoral immune response. At 1 month of age, the total gut bacterial cell counts per 1 g faeces were higher in vaginally delivered infants (9.9 × 10⁹, 95% CI 7.9 × 10⁹–1.2 × 10¹⁰) as compared to caesarean section delivered (3.1 × 10⁹, 95% CI 1.1 × 10⁹–8.6 × 10⁹) (p = 0.001). This distinction was mainly due to the greater number of bifidobacteria in vaginally delivered infants (1.9 × 10⁹, 95% CI 6.3 × 10⁸–5.6 × 10⁹ vs. 1.5 × 10⁶, 95% CI 4.1 × 10²–5.7 × 10⁹, respectively) (p = 0.001). During the first year of life, the total number of IgA-, IgG- and IgM-secreting cells was lower (p = 0.03, p = 0.02, p = 0.11, respectively) in infants born by vaginal delivery than in those born by caesarean section, possibly reflecting excessive antigen exposure across the vulnerable gut barrier. Conclusions: Our findings demonstrate that the mode of delivery may have, possibly via gut microbiota development, significant effects on immunological functions in the infant (http://www.clinicaltrials.gov/ct/gui/show/NCT00167700).

No abstract

The aim of the study was to assess the quantitative and qualitative differences of the gut microbiota in infants. We evaluated gut microbiota at the age of 6 months in 32 infants who were either exclusively breast-fed, formula-fed, nursed by a formula supplemented with prebiotics (a mixture of fructo- and galacto-oligosaccharides) or breast-fed by mothers who had been given probiotics. The Bifidobacterium, Bacteroides, Clostridium and Lactobacillus/Enterococcus microbiota were assessed by the fluorescence in situ hybridization, and Bifidobacterium species were further characterized by PCR. Total number of bifidobacteria was lower among the formula-fed group than in other groups (P=0.044). Total amounts of the other bacteria were comparable between the groups. The specific Bifidobacterium microbiota composition of the breast-fed infants was achieved in infants receiving prebiotic supplemented formula. This would suggest that early gut Bifidobacterium microbiota can be modified by special diets up to the age of 6 months.

Breast milk rich in saturated and low in n-3 fatty acids may be a risk factor for atopic dermatitis in the infant.

Objective: To assess the effects of maternal dietary and supplement intake of vitamins C and E on breast milk antioxidant composition (vitamin C, a-tocopherol and b-carotene) and their protective potential against the development of atopy in the infant. Design, subjects and methods: Mothers with atopic disease were recruited at the end of gestation and maternal sensitization was assessed by skin-prick testing. The 4-day food records of the mothers and breast milk samples were collected at the infants' age of 1 month. Infants' atopy was defined by the presence of atopic dermatitis during the first year of life and a positive skinprick test reaction at 12 months of age (n ¼ 34). Results: Maternal intake of vitamin C in diet but not as supplement was shown to determine the concentration of vitamin C in breast milk. A higher concentration of vitamin C in breast milk was associated with a reduced risk of atopy in the infant (OR ¼ 0.30; 95% CI 0.09-0.94; P ¼ 0.038), whereas a-tocopherol had no consistent relationship with atopy. The group at risk of suboptimal vitamin C supply from breast milk was identified as infants whose mothers suffer from food hypersensitivity. Conclusion: A maternal diet rich in natural sources of vitamin C during breastfeeding could reduce the risk of atopy in high-risk infants. Sponsorship: The Academy of Finland, the Juho Vainio Foundation and the Finnish Cultural Foundation.

Probiotic administration in the first months of life was well tolerated and did not significantly interfere with long-term composition or quantity of gut microbiota.

No abstract

No abstract