Evaluating Current Molecular Techniques and Evidence in Assessing Microbiome in Placenta-Related Health and Disorders in Pregnancy

Abstract

The microbiome is of great interest due to its potential influence on the occurrence and treatment of some human illnesses. It may be regarded as disruptions to the delicate equilibrium that humans ordinarily maintain with their microorganisms or the microbiota in their environment. The focus of this review is on the methodologies and current understanding of the functional microbiome in pregnancy outcomes. We present how novel techniques bring new insights to the contemporary field of maternal–fetal medicine with a critical analysis. The maternal microbiome in late pregnancy has been extensively studied, although data on maternal microbial changes during the first trimester are rare. Research has demonstrated that, in healthy pregnancies, the origin of the placental microbiota is oral (gut) rather than vaginal. Implantation, placental development, and maternal adaptation to pregnancy are complex processes in which fetal and maternal cells interact. Microbiome dysbiosis or microbial metabolites are rising as potential moderators of antenatal illnesses related to the placenta, such as fetal growth restriction, preeclampsia, and others, including gestational diabetes and preterm deliveries. However, because of the presence of antimicrobial components, it is likely that the bacteria identified in placental tissue are (fragments of) bacteria that have been destroyed by the placenta’s immune cells. Using genomic techniques (metagenomics, metatranscriptomics, and metaproteomics), it may be possible to predict some properties of a microorganism’s genome and the biochemical (epigenetic DNA modification) and physical components of the placenta as its environment. Despite the results described in this review, this subject needs further research on some major and crucial aspects. The phases of an in utero translocation of the maternal gut microbiota to the fetus should be explored. With a predictive knowledge of the impacts of the disturbance on microbial communities that influence human health and the environment, genomics may hold the answer to the development of novel therapies for the health of pregnant women.

The Role of Helicobacter pylori and Metabolic Syndrome-Related Mast Cell Activation Pathologies and Their Potential Impact on Pregnancy and Neonatal Outcomes

“…Considering pregnancy related-gut dysbiosis (Figure 1), it has been associated with pregnancy complications and negative fetal/neonatal outcomes [123]. Gut dysbiosis serves as a potential modulator of antenatal disorders related to the placenta, including fetal growth restriction, preeclampsia, maternal obesity, gestational diabetes mellitus, and preterm deliveries [123,124]. In this regard, a potential relationship between gestational diabetes mellitus and gut dysbiosis occurs in mothers and newborns, and there are influencing factors derived from gestational diabetes mellitus mothers on the gut dysbiosis of their newborns, including the vertical transmission of microbiota from mothers [125].…”

Special series on the role of the microbiome in reproduction and fertility

“…During pregnancy, the maternal microbiome undergoes dynamic changes to allow greater energy harvesting and decreased immune response that influence maternal health and fetal development. Imbalances in the gut microbiome have been linked to gestational complications, such as preeclampsia and gestational diabetes ( Stupak & Kwaśniewski 2023 ). Furthermore, specific bacterial species have been linked to preterm birth independently of clinically apparent infection, uterine anomalies, and other pregnancy complications ( Vidmar Šimic et al 2023 ).…”

“…Furthermore, specific bacterial species have been linked to preterm birth independently of clinically apparent infection, uterine anomalies, and other pregnancy complications ( Vidmar Šimic et al 2023 ). Additionally, the placental microbiome has been a subject of investigation but also controversy, with some studies identifying potential implications for fetal immune development and long-term health ( Stupak & Kwaśniewski 2023 ) while others have highlighted the inconsistencies in this research ( Walter & Hornef 2021 ).…”