**2.5 Consideration of the limitations of the included studies and potential sources of bias**

It is important to acknowledge the limitations of the included studies and potential sources of bias as they can influence the interpretation and generalizability of the findings. Some common limitations and potential sources of bias in studies related to neonatal microbial colonization and mode of delivery include: (1). Sample size: Numerous research in this field can have sample sizes that are not very large, which could reduce the statistical power and generalizability of the findings. Small sample sizes might not accurately reflect the population's variety, which could result in selection bias. (2). Selection bias: Studies may recruit participants from specific populations or healthcare settings, leading to selection bias. This can affect the representativeness of the sample and limit the ability to extrapolate the findings to a broader population. (3). Retrospective design: Some studies may use retrospective designs, relying on medical records or previously collected data. Retrospective studies may suffer from incomplete or inaccurate data, and researchers may have limited control over the variables studied. (4). Confounding factors: The association between the technique of delivery and neonatal microbial colonization can be influenced by a number of confounding variables. These elements include nursing habits, gestational age, antibiotic use, maternal microbiome, and mother health. The results may be skewed if these factors are not properly taken into account. (5). Lack of standardization: The methods used to assess microbial colonization can vary between studies, making it challenging to compare results directly. Differences in sampling techniques, DNA extraction, sequencing methods, and data analysis may contribute to variability in findings. (6). Cross-sectional nature: Some studies may have a cross-sectional design, which captures data at a single time point. This design may not allow for the evaluation of changes in microbial colonization over time, limiting the understanding of the dynamics of neonatal microbiota. (7). Lack of long-term followup: Long-term follow-up of neonates beyond the immediate postnatal period is essential to assess the potential impact of early-life microbial colonization on later

health outcomes. However, many studies may lack long-term follow-up data. (8). Vaginal seeding practice: Studies investigating the impact of vaginal seeding on neonatal microbial colonization are relatively new and may have limited data on the safety and long-term effects of this practice. This area requires further research to establish its clinical efficacy and safety. (9). Publication bias: Published studies may be more likely to report positive or statistically significant results, leading to publication bias. Negative or nonsignificant findings may be underreported, potentially skewing the overall literature on the topic. (10). To mitigate these limitations and potential sources of bias, future studies should aim for larger sample sizes, prospective designs, standardized methods, and rigorous control of confounding factors [31–33]. Additionally, conducting long-term follow-up studies can provide valuable insights into the lasting effects of neonatal microbial colonization on health outcomes. Collaborative efforts and multicenter studies can also enhance the generalizability of the findings and improve our understanding of the complex interactions between mode of delivery, neonatal microbial colonization, and health.

### **2.6 Addressing the controversies and debates surrounding vaginal seeding**

Vaginal seeding is a controversial practice that involves exposing infants born *via* cesarean section to the maternal vaginal microbes shortly after birth. While some proponents of vaginal seeding suggest that it may help promote a more diverse and beneficial microbial colonization in cesarean-born infants, there are significant controversies and debates surrounding its safety, efficacy, and potential risks. Limited Scientific One of the main controversies surrounding vaginal seeding is the lack of robust scientific evidence supporting its safety and long-term benefits. Most studies on the topic have been small, and there is a need for larger, well-designed clinical trials to establish the safety and effectiveness of vaginal seeding. Introducing maternal vaginal microbes to cesarean-born infants carries the risk of transferring harmful bacteria or infections to the newborn. The vaginal microbiome is diverse, and it can include potentially pathogenic microorganisms that may pose health risks to the vulnerable newborns. Vaginal seeding is not a standardized medical procedure, and there is no consensus on the best method for performing it. Different practitioners may use varied techniques, which can lead to inconsistencies and potential risks. While the intent of vaginal seeding is to promote a more diverse and beneficial microbial colonization, there is a concern that it may lead to unintended consequences [33–39]. The introduction of foreign microbes could potentially disrupt the delicate balance of the infant's microbiome and have unknown effects on their health. Vaginal seeding raises ethical concerns as it involves exposing infants to a practice that has not been thoroughly studied for its safety and effectiveness. Inclusion in clinical trials may be complicated due to the need for informed consent and potential risks. Before considering vaginal seeding, the potential benefits must be carefully weighed against the potential risks. Cesarean section is a lifesaving procedure in many cases, and the risks associated with vaginal seeding must be justified by significant potential benefits. Some researchers suggest that breastfeeding and skin-to-skin contact may provide beneficial microbial exposure for cesarean-born infants without the risks associated with vaginal seeding [37–43]. More research is needed to explore alternative approaches to promote a healthy microbiome in cesarean-born infants. In conclusion, while vaginal seeding has gained attention as a potential method to influence neonatal microbial colonization, it remains a

*Vaginal Seeding in Term Cesarean Section Is a Mandatory Condition for Improvement… DOI: http://dx.doi.org/10.5772/intechopen.114043*

controversial and debated practice. The lack of substantial scientific evidence, potential infection risks, and ethical considerations warrant caution and careful consideration before adopting vaginal seeding as a standard practice. Further, research is needed to better understand the safety and long-term effects of vaginal seeding and to explore alternative strategies to promote a healthy microbial colonization in cesarean-born infants. Until then, it is essential for healthcare providers and parents to engage in informed discussions about the potential risks and benefits of vaginal seeding and make decisions based on the best available evidence and individual circumstances [43–49].
