Oral microflora in infants delivered vaginally and by caesarean section

Abstract

BACKGROUND. Early in life, vaginally delivered infants exhibit a different composition of the gut flora compared with infants delivered by caesarean section (C-section); however, it is unclear whether this also applies to the oral cavity. AIM. To investigate and compare the oral microbial profile between infants delivered vaginally and by C-section. DESIGN. This is a cross-sectional case-control study. Eighty-four infants delivered either vaginally (n = 42) or by C-section (n = 42) were randomly selected from the 2009 birth cohort at the County Hospital in Halmstad, Sweden. Medically compromised and premature children (<32 weeks) were excluded. The mean age was 8.25 months (range 6-10 months), and parents were asked to complete a questionnaire on socioeconomic factors, lifestyle, and hygiene habits. Saliva was collected and analysed using checkerboard DNA-DNA hybridization. RESULTS. A higher prevalence of salivary Streptococcus salivarius, Lactobacillus curvata, Lactobacillus salivarius, and Lactobacuillus casei was detected in infants delivered vaginally (P < 0.05). The caries-associated bacteria Streptococcus mutans and Streptococcus sobrinus were detected in 63% and 59% of all children, respectively. CONCLUSION. A significantly higher prevalence of certain strains of health-related streptococci and lactobacilli was found in vaginally delivered infants compared with infants delivered by C-section. The possible long-term effects on oral health need to be further investigated.

Effect of Mode of Delivery on Early Oral Colonization and Childhood Dental Caries: A Systematic Review

“…Three studies rated weak [24] to moderate [25, 30] in quality assessment reported significant lower frequency of S. mutans detection among infants born by cesarean section compared with those vaginally delivered but only among younger groups (2 days, 1 month, and 3 months old). Instead, 6 studies that were considered to have moderate [14, 27, 28, 31] to strong [21, 23] methodological quality reported no significant differences in prevalence of oral colonization by S. mutans between groups by mode of delivery (Table 2). …”

“…Eight studies [14, 21, 23, 25, 27, 28, 30, 31] showed results on differences between groups by the mode of delivery in the prevalence of children with S. mutans (or mutans streptococci) and/or S. salivarius . Results were stratified according to the children’s age and summarized in Table 2.…”

“…Results were stratified according to the children’s age and summarized in Table 2. The prevalence of children with positive status varied across studies, ranging from 4.8 [30] to 79.9% [25] for S. mutans and from 53.3 [25] to 67.5% [31] for S. salivarius .…”

“…Two studies [25, 31] rated as moderate in quality assessment provided data on prevalence of salivary S. salivarius by mode of delivery. In both studies, cesarean section appeared as a protective factor against presence of S. salivarius in saliva for children aged between 1 and 10 months (Table 2).…”

“…The main characteristics of the studies including the outcomes assessed are described in Table 1. According to the methodological quality assessment, 5 studies were classified as strong [19-23], 1 study as weak [24], and the remaining studies were considered moderate [14, 25-31]. …”