Synbiotic is the combination of pre- and probiotics.
While prebiotic alone has been shown to support gut microbiome development in babies delivered via C-section, the use of synbiotics, in particular, has resulted in a greater abundance of Bifidobacterium breve.
This is a finding worthy of mention as Bifidobacterium is the dominant bacteria found in healthy infants who are breast-fed.
C-section babies also tend to suffer from a compromised microbiome as the beneficial Bifidobacterium is transmitted from mothers when babies pass through the birth canal.
Writing in the European Journal of Clinical Nutrition, researchers confirmed that synbiotics can support the restoration of important gut bacteria in infants born via C-section.
The study involved 224 healthy, term-born infants.
About half of them (121) were born via C-section. Of which, 86 per cent of them (104) were exposed to antibiotics administered to their mothers, in accordance with common hospital guidelines for C-section deliveries.
They were fully fed with either a synbiotic partially hydrolysed whey-based protein formula, or a commercially available intact protein formula containing only prebiotics.
These babies received either the synbiotic or prebiotic formula until 17 weeks of age.
The synbiotic used was the prebiotic combination of short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides in the ratio of nine to one, and the probiotic strain Bifidobacterium breve M-16V. This particular formula is already commercially sold in countries such as Malaysia, and other South East Asian countries like Thailand, Singapore, Vietnam, and Cambodia.
Their stool samples were then collected to find out the effects of the respective formulas on their gut microbiome.
Their stool pH, short-chain fatty acid concentrations, D- and L-lactate concentrations, and secretory immunoglobulin A (sIgA) were also measured.
Data from infants breastfed until at least 17 weeks of age were also used as reference.
Findings showed that the total relative abundance of Bifidobacteria had increased from baseline in both the synbiotic and prebiotic groups by week 17.
However, there was a significant increase in Bifidobacteria breve among those fed with the synbiotic formula as compared to those fed with the prebiotic formula.
Researchers said that this likely reflected the effects of the probiotic strain used in the synbiotic formula.
“Interestingly, the synbiotic compared to the prebiotic formula showed a more diverse bifidobacterial community with an increased abundance of Bifidobacterium breve, indicating the successful delivery of the probiotic strain without the competitive exclusion of endogenous infant-type bifidobacterial species, such as B. longum and B. bifidum,“ said the researchers.
Previously, Danone also conducted a similar study comparing the effects of the synbiotic, prebiotic, and control formula in infants born via C-section. The study was conducted in Singapore and Thailand.
Bifidobacterial increase more notable in c-sec babies taking synbiotic formula
In fact, the increase in bifidobacterial species diversity was more notably seen in babies taking synbiotic formula and born via C-section.
The increase in their bifidobacterial species was also closer to that of vaginally delivered infants receiving either the synbiotic or the prebiotic formula.
“The synbiotic-associated increase of bifidobacterial diversity was mainly attributed to an enrichment from baseline to 17 weeks in the C-section subgroup, bringing it closer to levels observed in vaginally-delivered infants receiving either the prebiotic or synbiotic formula,” said the researchers.
Restoration of other species
Babies born via C-section and taking the synbiotic formula also reported a restoration of Parabacteroides at week 17, and Bacteroides spp. to mirror the levels found in vaginally–born infants.
Both of these bacteria are associated with a lower abundance in C-section babies when compared to vaginally-born babies.
“The synbiotic formula was observed to restore the levels of the two Bacteroidota genera in C-section born closer to that of the vaginally-delivered infants (formula-fed and breastfed) with significantly increased relative abundance of Parabacteroides at 17 weeks (p = 0.0007) and Bacteroides at 12 months (p = 0.0005) compared to C-section born infants receiving Control formula," said the researchers.
This is an interesting finding as even breastfed C-section delivered babies did not show a restoration in Bacteroides.
The restoration of Bacteroidota was also observed beyond the intervention period.
“In this study, we did observe a recovery of Bacteroidota from 17 weeks onwards, suggesting that the synbiotic formulation can still partially correct the lack of Bacteroidota at a later stage of gut microbiota development,” the researchers added.
Increase in branched-chain SCFAs in synbiotic group
On the other hand, there was an increase in branched-chain short-chain fatty acids in babies taking the synbiotic formula.
The researchers attributed this to the differences in protein composition of the synbiotic and prebiotic formulas.
The synbiotic formula contains whey and contains partially hydrolysed protein, while the prebiotic formula contains whey casein and intact protein.
“Some minor differences for the synbiotic vs. the prebiotic formula were observed, i.e. an increased abundance of Cutibacterium spp. and Negativicoccus spp., along with increased branched-chain SCFAs, which may be attributed to differences in protein composition.
“Branched-chain SCFAs are derived from branched-chain amino acids and therefore provide an indicator of protein fermentation activity and both bacterial taxa have been correlated with protein-degrading activity,” the researchers explained.
Source: European Journal of Clinical Nutrition
Restoration of gut microbiota with a specific synbiotic-containing infant formula in healthy Chinese infants born by cesarean section.
https://doi.org/10.1038/s41430-025-01571-8
Authors: Wang, Y., Wopereis, H., Kakourou, A. et al.
