The role of the maternal gut microbiome in regulating endocrine function during pregnancy and postpartum: implications for neonatal health

 Corresponding author: Aikaterini Sousamli. Copyright © 2025 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution License 4.0. The role of the maternal gut microbiome in regulating endocrine function during pregnancy and postpartum: implications for neonatal health Dimitra Patronidou 1, Chrysoula Taskou 2, Chrysoula-Rozalia Athanasiadou 1, Panagiota Dourou 1 and Aikaterini Sousamli 1, * 1 Department of Midwifery, Faculty of Health and Care Sciences, University of West Attica, 12243 Athens, Greece. 2 Alexandra Maternity Hospital, 11528 Athens, Greece. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 Publication history: Received on 01 June 2025; revised on 05 July 2025; accepted on 08 July 2025 Article DOI: https://doi.org/10.30574/wjarr.2025.27.1.2601 Abstract Objective: This systematic review aims to examine the role of the maternal gut microbiome in regulating endocrine function during pregnancy and the postpartum period, and its effects on neonatal health. Additionally, it assesses the effectiveness of microbiome-targeted interventions and identifies knowledge gaps in the current literature to inform future research directions. Design and Methods: A systematic literature review was conducted following PRISMA 2020 guidelines. Searches were performed in PubMed, Scopus, and the Cochrane Library. Out of 94 identified records, 19 studies met the inclusion criteria based on the PICOST framework. The included studies were critically appraised using the Caldwell framework. Results: Findings indicate that metabolites derived from the maternal gut microbiome influence maternal endocrine function, affecting maternal weight and neonatal outcomes such as birth weight and length. Specific microbial profiles were found to predict gestational age and neonatal development, while some were linked to excessive fetal growth. In cases of gestational diabetes mellitus, notable dysbiosis was observed in both mothers and their newborns, with significant implications for health. The use of probiotics showed mixed results, beneficial in some studies, ineffective in others. Conclusion: The maternal gut microbiome plays a critical role in maternal and neonatal health by interacting with the endocrine system and influencing key developmental outcomes. However, this emerging field remains underresearched. Further longitudinal and mechanistic studies are needed to clarify causal pathways and to evaluate the clinical utility of microbiome-based interventions during pregnancy. Keywords: Maternal Gut Microbiome; Pregnancy; Postpartum Period; Endocrine Function; Hormonal Regulation; Neonatal Health 1. Introduction Understanding the role of the maternal gut microbiome in regulating endocrine function during pregnancy and postpartum is a growing area of interest in maternal-child health. The gut microbiota influences host metabolism, immunity, and hormonal balance functions that are especially critical during gestation. Disruptions in microbial composition have been associated with adverse pregnancy outcomes and long-term consequences for neonatal health [1–3]. This systematic review aims to synthesize current findings on this topic and highlight gaps in the literature. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 765 1.1. The Role of the Gut Microbiome in Humans The human gut microbiome comprises approximately 35,000 bacterial species, alongside archaea, fungi, and viruses, forming a complex and symbiotic ecosystem [1–5]. While viruses are often excluded from formal definitions, they are present within the microbiome [6]. The composition of the gut microbiota varies by geography, diet, lifestyle, age, genetics, medications, and environmental exposures, including breastfeeding and maternal oral microbiota [1,6–9]. The dominant phyla in a healthy gut are Firmicutes and Bacteroidetes, followed by Actinobacteria, Proteobacteria, Fusobacteria, and Verrucomicrobia [10]. Key genera include Lactobacillus, Clostridium, Bacteroides, Prevotella, and Bifidobacterium [11]. The gut microbiome contributes to nutrient and xenobiotic metabolism, energy homeostasis, immune maturation, intestinal barrier function, and neurological development [2,6,7,12]. It also plays a role in host-microbe communication via neuroendocrine and immunometabolic pathways and is thus considered a vital organ [1,6,10]. Short-chain fatty acids (SCFAs), mainly acetate, propionate, and butyrate, produced by microbial fermentation of dietary fibers and human milk oligosaccharides, support epithelial integrity, modulate inflammation, and regulate appetite, blood pressure, weight, and glucose metabolism [4,6,13–16]. SCFAs interact with G-protein-coupled receptors, influence hormone secretion, and are linked to insulin sensitivity and reduced adiposity [16-18]. Butyrate, in particular, has antiinflammatory and possibly antitumor effects [6], while higher levels of SCFAs are associated with reduced asthma and atopy risk [19]. The microbiome plays a dual role with the immune system, influencing T cell differentiation, neutrophil regulation, and immune tolerance [1,19–22]. Dysbiosis is associated with immune-related diseases such as eczema and allergies, marked by shifts in bacterial families [7,12]. Via the gut–brain axis, gut microbes affect neurotransmitter production and are linked to emotional and cognitive functions [10,11,14]. Gut bacteria also synthesize vitamins and regulate bile acid metabolism, affecting lipid peroxidation, hepatic fatty acid synthesis and triglyceride storage [1,6,20]. Moreover, the gut microbiome modulates absorption of iodine, selenium, iron, and zinc [17], contributing to micronutrient homeostasis [15]. It also regulates endocrine function by interacting with insulin, estrogens, and androgens [17,18]. Alterations in microbial taxa are associated with insulin resistance and glucose levels [14,17,23]. Microbiota-related mechanisms include inflammation modulation, fat storage, and amino acid and bile acid metabolism [24]. Overall, the gut microbiome plays a pivotal role in human physiology, particularly during pregnancy, where it can influence hormonal balance, immune tolerance, and metabolic adaptation. 1.2. The Gut Microbiome During Pregnancy Pregnancy is characterized by profound hormonal, metabolic, and immunological changes essential for fetal development, which also influence the maternal gut microbiome [9]. The microbiota, mainly residing in the colon, undergoes trimester-specific alterations influenced by maternal age, pre-pregnancy BMI, height, residence, and hematological factors [14,25,26]. Throughout pregnancy, microbial diversity and composition shift: alpha diversity declines, while beta diversity increases, along with elevated Firmicutes/Bacteroides ratios and increased abundance of Actinobacteria, Proteobacteria, Blautia, Collinsella, and Bifidobacterium species [10,27]. These changes are associated with reduced insulin sensitivity and enhanced nutrient absorption to support gestation [10,27]. A rise in proinflammatory cytokines and gut bacteria helps mobilize fat stores to fuel fetal growth, while increased SCFA production, elevated leptin, insulin, and insulin resistance further adapt maternal metabolism [11,15,28,29]. Notably, the third-trimester gut microbiome resembles a dysbiotic state, similar to that seen in metabolic syndrome, yet is physiologically beneficial during pregnancy [8,27]. A progressive decrease in microbial diversity is observed, alongside increases in Proteobacteria, Actinobacteria, Enterobacteriaceae, and Streptococcus spp. [17]. Cytokine levels rise significantly in late gestation, with low-grade mucosal inflammation [27]. The endocrine environment, particularly rising levels of progesterone and estrogens, modulates the microbiome through mechanisms such as reduced gut motility [11,17]. Progesterone may promote vertical transmission of beneficial microbes, like Bifidobacterium, which increase in late pregnancy and support infant gut and immune health [7,18]. The gut microbiota also impacts maternalfetal energy metabolism. Taxa such as Bacteroides, Staphylococcus, Lachnospiraceae, Prevotellaceae, and Ruminococcaceae are associated with adiposity and metabolic profiles [17]. Elevated Firmicutes, Proteobacteria, and Actinobacteria in late gestation contribute to fetal weight gain and glucose transfer, but may induce maternal hyperglycemia [11]. Cortisol levels increase under CRH influence toward term, aiding in metabolic homeostasis and preparation for labor. Changes in insulin and glycogen also support maternal-fetal glucose balance [5]. Dysbiosis during pregnancy may contribute to complications and affect offspring health. Thus, maintaining microbial balance through nutrition and probiotics/prebiotics is considered essential [14]. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 766 1.3. Initiation of Gut Microbiome Colonization Recent studies using advanced techniques have identified bacterial DNA in the amniotic fluid, uterus, placenta, and meconium, challenging the long-standing view of the womb as a sterile environment [6,7]. These findings suggest that microbial colonization may begin in utero through maternal–fetal microbial exchange, potentially influencing fetal immune system development. However, many studies fail to detect a distinct fetal microbiome, attributing previous findings to contamination during sampling, as no viable bacterial colonies were observed [6,7]. Despite the ongoing debate, the neonatal gut is widely believed to encounter its first significant microbial exposure during passage through the birth canal [30]. A recent systematic review comparing evidence for in utero colonization versus the sterile womb hypothesis concluded that the majority of data supports the sterility of the intrauterine environment, with only limited and inconclusive evidence against it [31]. 1.4. Interaction Between the Maternal Gut Microbiome and the Fetus The fetal and neonatal gut microbiome is shaped by the maternal gut microbiota and perinatal factors [10]. Maternal microbes may be vertically transmitted via the placenta, facilitated by increased gut permeability and altered placental integrity, allowing microbial components to reach the fetus [23]. While direct bacterial transfer remains under debate, it is well established that immune molecules and microbiota-derived metabolites, such as TLR ligands, SCFAs, neurotransmitters, B vitamins, folate, and polyphenols, cross the placenta and influence fetal gene expression, neurodevelopment, and the gut–brain axis [11,21]. These factors support immune and nervous system maturation, thalamocortical development, and brain connectivity, with long-term effects on cognition and behavior. For instance, maternal microbiome diversity and butyrate-producing bacteria have been associated with reduced anxiety behaviors in children [11]. The maternal microbiota also influences fetal HPA axis regulation, cortisol production, and early stress responses through microbial antigens and cytokines [11]. Maternal stress and dysbiosis can disrupt this system, contributing to necrotizing enterocolitis and impaired fetal development [5]. Additionally, SCFAs modulate IL-6, T cell function, epithelial integrity, and neuroimmune development [11,32,33]. Gut eubiosis promotes fetal myelination, whereas dysbiosis may lead to neuroinflammation and neuronal damage [11]. Low maternal acetate is linked to preeclampsia, while SCFA signaling may protect against offspring obesity [11, 18]. 1.5. The Neonatal Gut Microbiome At and after birth, the neonatal gut is colonized by microbes from the maternal gut, vagina, mouth, skin, and the environment [34]. Maternal sources contribute differentially, fecal, vaginal, oral, and skin microbiota, with fecal influence increasing over time [34]. Vertical transmission is key, as maternally derived microbes are more likely to persist than those from external sources [7], though evidence remains limited [25]. Gut colonization is influenced by gestational age, sex [34], maternal genetics, delivery mode, breastfeeding, diet, antibiotic exposure, and smoking [19,21]. Vaginal delivery promotes maternal-like gut colonization [35], while cesarean delivery is linked to reduced diversity, delayed immune development, and higher risk of asthma and allergies [21]. Breastfeeding fosters Bifidobacteria through natural probiotics, while formula feeding promotes Clostridia and Bacteroides [22]. Breast milk provides immunoglobulins, cytokines, and protective IgG against E. coli [21]. It contributes ~27% of the infant’s microbiome in the first year; another 10% comes from maternal skin [21]. The neonatal microbiome supports immune maturation, nutrient metabolism, and pathogen defense [25,36]. Early colonizers include Enterococcus, Staphylococcus, and Enterobacteriaceae, followed by Lactobacillus, Clostridium, Bifidobacterium, and Bacteroides [37]. By age one, microbial diversity increases, approaching adult-like composition dominated by Actinobacteria, Firmicutes, and Bacteroidetes [35,37]. Development progresses in three phases, developmental (0–14 months), transitional (15–30 months), and stabilization (31–46 months) [19], with a shift from facultative to obligate anaerobes as gut oxygen levels drop [21]. The neonatal microbiome, composed mainly of Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, and Verrucomicrobiae, is more adaptable than the adult microbiome [6,21]. 1.6. Gut Microbiome Dysbiosis During pregnancy, maternal gut dysbiosis refers to the imbalance or maladaptation of the gut microbiome, influenced by factors such as obesity, diet, inflammation, stress, infections, and medication use [11]. Dysbiosis has been linked to adverse maternal and neonatal outcomes, including preeclampsia, gestational diabetes, intrauterine growth restriction, and increased risk of metabolic, immune, and neurodevelopmental disorders in the offspring, such as obesity and autism [1,16,26,30,38]. Vertical transmission of a dysbiotic microbiome may occur during gestation or delivery, affecting neonatal gut colonization and development [15,23]. For example, gestational diabetes alters maternal and neonatal microbiota composition, reducing microbial diversity and promoting pro-inflammatory bacterial profiles [10,19,23]. Similarly, maternal stress and elevated cortisol levels are associated with reduced beneficial bacteria and increased potential pathogens in the neonate [18]. Early-life dysbiosis has been associated with conditions such as NEC, sepsis, World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 767 asthma, eczema, and metabolic dysfunction [6,33,34]. Probiotic use during pregnancy may help restore microbial balance and support maternal and neonatal health [39]. 1.7. Probiotics and Prebiotics Probiotics are live microorganisms which, when administered in adequate amounts, confer health benefits to the host [40]. They modulate gut microbiota composition and function, aiming to counteract the negative effects of dysbiosis [41,42]. Generally considered safe, probiotics support maternal and neonatal health by promoting symbiotic bacteria, enhancing intestinal barrier function, and regulating immune responses [14]. They also help restore deficiencies in the neonatal microbiome [34], prevent inflammatory gut disorders [12], and stimulate the growth of beneficial microbes, including bacteria and fungi [43]. During and after pregnancy, probiotic supplementation may reduce the risk of gestational diabetes, preterm birth, mastitis, constipation, postpartum depression, infant atopic dermatitis, and Group B Streptococcus colonization. They are also associated with improved glucose metabolism, reduced inflammation, and enhanced neonatal gut colonization [43]. Prebiotics, typically non-digestible oligosaccharides, support probiotic activity. When combined with probiotics, they form synbiotics. These fibers are selectively fermented by gut bacteria to produce SCFAs, which contribute to intestinal health [2]. Prebiotics enhance gut motility, epithelial integrity, and mucosal maturation, while limiting pathogen growth [12]. Postnatal maternal intake of prebiotics increases SCFA levels in offspring, which may cross the blood–brain barrier and influence brain function [33]. 1.8. Antibiotics Antibiotic use disrupts the maternal vaginal microbiome, a major contributor to neonatal gut colonization [21]. This disruption is associated with increased asthma severity, heightened anxiety and reduced social behavior in offspring [14], and a higher risk of childhood-onset Crohn’s disease [39]. Notably, amoxicillin/clavulanic acid use has been linked to a fourfold increased risk of NEC [30]. Prenatal antibiotic exposure alters neonatal gut microbiota. For instance, intrapartum antibiotic prophylaxis for Group B Streptococcus is transferred via the umbilical cord and reduces beneficial Bifidobacterium, while increasing potentially pathogenic Escherichia and Enterococcus strains [7]. It also reduces Lactobacillus, essential for dendritic cell maturation, potentially delaying neonatal immune responses and increasing the risk of early-onset sepsis [21]. Co-administration of probiotics is recommended to mitigate the adverse effects of antibiotics [39]. These findings underscore the gut microbiome's crucial role in systemic homeostasis across life stages, particularly in conditions like gestational diabetes and obesity. Restoring microbiome balance through probiotics and prebiotics has shown promise and is a growing area of research. The following sections of this review will explore in detail the maternal gut microbiome’s role in hormonal regulation, fetal development, neonatal outcomes, and the impact of maternal dysbiosis and microbiome-targeted interventions on neonatal endocrine and metabolic health. 2. Design and Methods To identify the literature for review, a structured search was conducted in the electronic databases PubMed/Medline, Scopus, and Cochrane Library. The searches were performed between November 2024 till May 2025. covering literature published from 2014 to 2024. Initially, a broad search strategy was applied, which was then refined into three specific search algorithms, each targeting key concepts: (1) gut microbiome, (2) endocrine function, (3) pregnancy, (4) postpartum period, and (5) neonatal outcomes. The search terms included both MeSH terms and free-text keywords combined using Boolean operators (AND/OR). Table 1 below presents the databases used, the specific search algorithms applied in each, and the central research question that guided the search process. Only English language articles were considered. Inclusion criteria comprised peer-reviewed original research studies, systematic reviews, and meta-analyses focusing on the maternal gut microbiome and endocrine interactions during pregnancy and their effects on neonatal health. Studies involving animals, non-pregnant populations, or unrelated outcomes were excluded. After removing duplicates, titles and abstracts were screened for relevance, and full-text articles were assessed based on predefined eligibility criteria. Systematic theoretical reviews provide valuable insights into medical practices and help identify research gaps across a wide range of medical and social issues. They aim to identify all relevant studies that address a specific research question [44]. This systematic theoretical literature review was conducted in accordance with the steps outlined in the PRISMA Statement [45]. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 768 Table 1 Search Algorithms and Research Question per Database Search Algorithm No. Database Search Terms Research Question 1 PubMed/Medline (Gut-microbiome OR Gut-microbiota OR Intestinal-microbiota OR Gastrointestinalmicrobiome OR Dysbiosis OR Microbiomecomposition OR Probiotics OR Prebiotics) AND (Endocrine-function OR Hormonal-regulation OR Insulin OR Cortisol OR Thyroid-hormones OR Estrogen OR Progesterone OR Glucocorticoids OR Adiponectin OR Leptin OR Ghrelin OR HPA-axis OR Hypothalamic-Pituitary-Adrenal-axis) AND (Pregnancy OR Postpartum OR Gestation OR Prenatal OR Perinatal OR Maternal) AND (Neonatal-health OR Neonatal-outcomes OR Neonatal-endocrine-function OR Neonatalmetabolism OR Birth-weight OR Neonatal-growth OR Neonatal-immune-development OR Neonatalobesity OR Neonatal-diabetes OR Neonatalmetabolic-syndrome To investigate the role of the maternal gut microbiome in regulating endocrine function during pregnancy and childbirth: implications for neonatal health. 2 Scopus (“Gut microbiome” OR “Gut microbiota” OR “Intestinal microbiota” OR “Gastrointestinal microbiome” OR “Dysbiosis” OR “Microbiome composition” OR “Probiotics” OR “Prebiotics”) AND (“Endocrine function” OR “Hormonal regulation” OR “Insulin” OR “Cortisol” OR “Thyroid hormones” OR “Estrogen” OR “Progesterone” OR “Glucocorticoids” OR “Adiponectin” OR “Leptin” OR “Ghrelin” OR “HPA axis” OR “Hypothalamic Pituitary Adrenal axis”) AND (“Pregnancy” OR “Postpartum” OR “Gestation” OR “Prenatal” OR “Perinatal” OR “Maternal”) AND (“Neonatal health” OR “Neonatal outcomes” OR “Neonatal endocrine function” OR “Neonatal metabolism” OR “Birth weight” OR “Neonatal growth” OR “Neonatal immune development” OR “Neonatal obesity” OR “Neonatal diabetes” OR “Neonatal metabolic syndrome”) To investigate the role of the maternal gut microbiome in regulating endocrine function during pregnancy and childbirth: implications for neonatal health. 3 Cochrane Library (Gut AND microbiome OR Gut AND microbiota OR Intestinal AND microbiota OR Gastrointestinal AND microbiome OR Dysbiosis OR Microbiome AND composition OR Probiotics OR Prebiotics) AND (Endocrine AND function OR Hormonal AND regulation OR Insulin OR Cortisol OR Thyroid AND hormones OR Estrogen OR Progesterone OR Glucocorticoids OR Adiponectin OR Leptin OR Ghrelin OR HPA AND axis OR Hypothalamic AND Pituitary AND Adrenal AND axis) AND (Pregnancy OR Postpartum OR Gestation OR Prenatal OR Perinatal OR Maternal) AND To investigate the role of the maternal gut microbiome in regulating endocrine function during pregnancy and childbirth: implications for neonatal health. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 769 (Neonatal AND health OR Neonatal AND outcomes OR Neonatal AND endocrine AND function OR Neonatal AND metabolism OR Birth AND weight OR Neonatal AND growth OR Neonatal AND immune AND development OR Neonatal AND obesity OR Neonatal AND diabetes OR Neonatal AND metabolic AND syndrome) 2.1. Inclusion and Exclusion Criteria To determine the inclusion and exclusion criteria of the studies, the PICOST framework was applied [46]. Specifically, studies were included if they involved pregnant women (Population), investigated the maternal gut microbiome (Intervention), and included a comparison related to endocrine function (Comparison). Eligible studies were required to report outcomes associated with neonatal health (Outcome). Regarding study design, only primary research studies, both quantitative and qualitative, were considered; studies not available in full text or published in languages other than English were excluded. Finally, with respect to timeliness, the review was limited to studies published between 2014 and 2024; those published outside this period were not included. 2.2. Search Results and Data Extraction The initial search was conducted in the PubMed, Scopus, and Cochrane Library databases. A total of 109 records were identified. Among these, 25 were retrieved from PubMed/Medline, 83 from Scopus, and 1 from the Cochrane Library. After removing 25 duplicate records, 84 unique records remained for screening. Table 2 provides an overview of the number of articles retrieved from each database, the total number of duplicate entries, and the final number of articles included after de-duplication. Table 2 Number of Articles by Database and Deduplication Process Database Total with Duplicates Duplicate Entries Total without Duplicates PubMed/Medline Scopus Cochrane Library 109 25 84 25 83 1 Following the initial database search, each article was carefully screened to determine its relevance to the study topic. The first level of screening involved a review of article titles and abstracts to eliminate those unrelated to the research question: the role of the maternal gut microbiome in the regulation of endocrine function during pregnancy and childbirth, and its implications for neonatal health. As noted above, not all studies were deemed eligible. Following the initial screening, 74 articles were excluded. The remaining 10 articles were assessed in detail. During the full-text retrieval phase, 1 article was found to be inaccessible, resulting in 9 articles eligible for analysis. An additional 10 relevant articles were identified and added, bringing the total number of included studies to 19. All studies were evaluated for methodological quality using the Caldwell appraisal framework [47], which is suitable for both quantitative and qualitative research. The selection process is visually presented in the PRISMA 2020 flow diagram shown in Figure 1. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 770 Figure 1 PRISMA 2020 Flow Diagram Subsequently, the following variables were extracted from the selected studies: the first author, year of publication, type of study, sample size relevant to the target population, overall sample size, method and type of data collection, comparison group (if available), main findings of each study, specific findings related to the research question on mode of delivery, follow-up with the sample (if applicable), study limitations, journal of publication, and country in which the study was conducted. 3. Results A total of 19 scientific articles published between January 1, 2014, and January 1, 2024, were analyzed. These studies investigated the role of the maternal gut microbiome in regulating endocrine function during pregnancy and childbirth, as well as the implications for neonatal health. The studies were conducted across various countries, including China (n=8), Australia (n=2), Ireland (n=2), Malta (n=1), Denmark (n=1), the United States (n=1), Israel (n=1), Zimbabwe (n=1), Germany (n=1), and Finland (n=1). Each article was reviewed in detail, and essential data were extracted and recorded in a Microsoft Excel spreadsheet, organized in ascending chronological order based on the publication date, as outlined in Subsection 2.2. Table 3 presents a summary of key findings from the 19 reviewed studies, with a particular focus on the role of the maternal gut microbiome in hormonal regulation. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 771 Table 3 Concise overview of the principal characteristics and findings of the reviewed studies First Autho r Title Ye ar Journal of Publica tion Coun try Type of Study Partici pants Target Group Measur ement and Data Collecti on Method Compa rison Group Measure d Outcome Main Findings Specif ic Findin gs Relate d to Mode of Delive ry Followup with Sample Study Limitati ons 1 Abela, Alexia G Prenatal and early life factors and type 1 diabetes 20 22 Endocri ne Malta Retrospective casecontrol study A total of 89 mothe rs of childre n with type 1 diabet es and 89 mothe rs of health y childre n partici pated. 89 mothe rs of childre n with type 1 diabet es An intervie w was conduct ed. 89 mother s of healthy childre n The possible role of prenatal and perinatal factors as causes in the developm ent of type 1 diabetes was investigat ed. Handwas hing before meals, bathing frequency, and the overall stress score were found to be positively associated with the developm ent of type 1 diabetes. Regar ding the mode of deliver y, 16.9% of patient s with type 1 diabet es and 18% of health y individ uals were born by cesare an sectio n. No followup contact with the sample was reporte d. Limitatio ns of the present study include the lack of assessme nt of childhoo d behavior al habits through the question naire, as well as the retrospec tive study design rather than a prospecti ve one. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 772 2 Lan Yehui The relationship between gut microbiota, short-chain fatty acids, and glucolipid metabolism in pregnant women with large for gestational age infants 20 23 Journal of Applied Microbi ology China Observational prospective cohort study A total of 49 pregna nt wome n partici pated, of whom 4 partici pants were exclud ed. Eighte en wome n who gave birth to largeforgestati onalage neonat es. Fecal samples were collecte d from each pregnan t woman prior to delivery for the analysis of gut microbi ota composi tion and shortchain fatty acids. Addition ally, blood samples were obtaine d at 24– 28 weeks of gestatio n, as well as shortly before delivery 27 women who gave birth to neonat es approp riate for gestati onal age. The associatio n between the gut microbiot a of SCFAs and glucolipid metabolis m was investigat ed in women with large-forgestation al-age infants. Multiple distinct taxonomic strains, particularl y the phylum Firmicute s and the genera Prevotella and Clostridiu m, may contribute to excessive fetal growth and the birth of large-forgestationa l-age neonates. Additional ly, these strains might be associated with lower serum HDL levels. No finding s regard ing the mode of deliver y were report ed. No followup contact with the sample was reporte d. Limitatio ns of the present study include the inability to account for lifestyle and dietary factors of the populatio n, which may influence the gut microbio me, SCFAs, and glucoselipid metaboli sm, as well as the small sample size. 3 Halkjæ r Sofie I. No effect of multi-strain probiotic supplementa 20 23 Nutritio n, Metabol ism and Den mark Randomized, doubleblind placebo-controlled study A total of 50 obese pregna The focus group consist Two visits were conduct The compar ison group The effects of probiotic suppleme After probiotic suppleme ntation, From the group of There was no followup Limitatio ns of the present study World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 779 changes were observed in glucose levels or lipid metabolis m. ed the placeb o capsul e, 12 deliver ed by cesare an sectio n and 14 vagina lly. 9 Priyad arshini Medha Maternal short-chain fatty acids are associated with metabolic parameters in mothers and newborns 20 14 Transla tional Researc h USA Prospective study A total of 20 pregna nt wome n partici pated. A total of 20 pregna nt wome n partici pated. Blood samples were collecte d between 36 and 38 weeks of gestatio n, and neonatal anthrop ometric measure ments were taken after delivery. No control group is reporte d. The possible correlatio n between serum LOBA levels and key metabolic paramete rs in the mother and neonate was investigat ed. It was observed that acetate levels are associated with maternal weight gain and adiponecti n levels, while propionat e levels are negatively correlated with maternal leptin levels, as well as neonatal length and weight. The mode of deliver y is not report ed. There was no followup contact with the sample reporte d. Limitatio ns of the present study include the relatively small sample size and its conducti on in a single hospital setting, which may limit the generaliz ability of the findings and obscure potential World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 780 regional variation s. 1 0 Gao Yuan Maternal gut microbiota during pregnancy and the composition of immune cells in infancy 20 22 Frontier s in Immun ology Austr alia Cohort study A total of 286 mothe r– infant pairs partici pated A total of 286 pregna nt wome n and their newbo rns partici pated as mothe r infant pairs. Stool samples were collecte d from pregnan t women at 36 weeks of gestatio n, umbilica l cord blood was obtaine d at birth, and peripher al blood samples were collecte d from infants at 6 and 12 months of age. No control group is mentio ned The relations hip between the maternal gut microbio me during pregnanc y and the compositi on of the infant's immune cells in umbilical cord blood and periphera l blood during the first year of life was investigat ed. It was found that the maternal gut microbio me during pregnancy contribute s to the shaping of both innate and adaptive componen ts of the infant's immune system after birth. The mode of deliver y is not report ed. There was no followup contact with the sample reporte d. Limitatio ns of the present study include the use of immunol ogical measures that are nonfunctiona l and limited to samples from umbilical cord blood and peripher al blood. Moreove r, with regard to bacterial groups, not all taxa have been studied in detail, nor have the distinct biologica l World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 781 functions and the specific significan ce of each group been fully investiga ted. 1 1 Gough Ethan K. Maternal fecal microbiome predicts gestational age, birth weight and neonatal growth in rural Zimbabwe. 20 21 EBioMe dicine Zimb abwe Cluster-randomized trial A total of 207 mothe rs and their newbo rns partici pated. A total of 207 mothe rs and their newbo rns partici pated. Stool samples were collecte d from the women during pregnan cy and one month postpart um. No control group was reporte d The identifica tion of maternal microbes and metabolic functions potentiall y influencin g gestation al age at birth, birth size, or neonatal growth was investigat ed. Additiona lly, the effects of the SHINE WASH interventi on, baseline It was found that the maternal fecal microbio me during pregnancy , particularl y the abundanc e of resistant starch degraders , is a significant factor contributi ng to birth weight and neonatal growth, and to a lesser extent to gestationa l age, in 195 wome n deliver ed vagina lly. Followup with the sample was conduct ed one month postpar tum with the mother s, along with intensiv e blood collecti on from the infants at 1, 3, 6, 12, and 18 months of age. A limitatio n of the present study is that a large fraction of the sequence d reads could not be assigned. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 782 hygiene, hygienerelated factors, and maternal character istics on the maternal fecal microbio me were examined . infants of rural Zimbabwe an mothers consumin g a maizerich diet. 1 2 Sanjay Patole Effect of Bifidobacteri um breve M16V supplementa tion on fecal bifidobacteri a in preterm neonates--a randomised doubleblind placebo controlled trial 20 14 PLOS One Austr alia Randomised Double Blind Placebo Controlled Trial A total of 159 newbo rns partici pated. The focus group consist ed of 79 newbo rns who receiv ed the probio tic. Stool samples were collecte d from the newbor ns before and after 3 weeks of supplem ent administ ration. The control group consist ed of 80 newbor ns who receive d the placebo capsule . The product quality was investigat ed, and it was hypothesi zed that suppleme ntation with Bifidobac terium breve M16V would increase the number of B. breve in stool without It was found that suppleme ntation with B. breve M16V is safe and effective in increasing B. breve levels in the stool of very low birth weight preterm infant A total of 107 newbo rns were deliver ed by cesare an sectio n, of whom 58 receiv ed the probio tic and 49 receiv ed the placeb o capsul e. There was no followup contact with the sample reporte d. A limitatio n of the present study is that the administ ration of the study supplem ent began as soon as the neonate was ready for feeding, without waiting for meconiu m passage. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 783 adverse effects. 1 3 Minglia n Su Diversified gut microbiota in newborns of mothers with gestational diabetes mellitus 20 18 PLOS One China Observational, crosssectional study A total of 34 fullterm newbo rns partici pated, of whom the mothe rs of 20 had GDM. The focus group consist ed of 20 newbo rns whose mothe rs develo ped GDM. Meconiu m samples were collecte d from the newbor ns. The control group consist ed of 14 newbor ns whose mother s did not develo p GDM. The potential impact of maternal gestation al diabetes on the neonatal gut microbiot a was investigat ed. Taxonomi c analyses indicated that the overall bacterial compositi on differed significant ly according to maternal diabetes status, with the microbio me of the GDM group exhibiting lower alpha diversity compared to the control group. However, bacteria in the newborns of the class A2 GDM group showed Thirtyfour newbo rns were deliver ed by cesare an sectio n. There was no followup contact with the sample reporte d. A limitatio n of the present study is the small sample size, as well as the possible administ ration of treatmen t for GDM in some mothers. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 784 no statisticall y significant variation compared to those of control newborns, which could be attributed to the additional insulin interventi on. 1 4 Niels van Best Influence of probiotic supplementa tion on the developing microbiota in human preterm neonates 20 20 Gut Microbe s Germ any Longitudinal observational study A total of 80 preter m newbo rns partici pated. A total of 80 preter m infants partici pated. Stool samples were collecte d from the newbor ns. The control group consist ed of newbor ns who did not receive probiot ics. The effect of probiotic administr ation on microbiot a developm ent in preterm infants was investigat ed. Successful transient colonizati on by probiotic bacteria was observed, along with a significant impact on the endogeno us microbiot a, characteri zed by a reduced abundanc e of bacterial The majori ty of neonat es were deliver ed by cesare an sectio n. There was no followup contact with the sample reporte d. Limitatio ns of the present study include the relatively small sample size, the observati onal nature of the study, and the sequenti al enrollme nt of the three patient groups. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 785 taxa associated with the developm ent of NEC. 1 5 Wang Jinfeng Dysbiosis of maternal and neonatal microbiota associated with gestational diabetes mellitus 20 18 Gut China Observational, crosssectional study A total of 140 newbo rns and 346 pregna nt wome n partici pated. A total of 140 newbo rns and 346 pregna nt wome n partici pated. Samples of saliva, pharyng eal aspirate s, meconiu m, and amniotic fluid were collecte d from the newbor ns, while saliva, stool, and vaginal secretio ns were collecte d from the pregnan t women. No control group was reporte d. Potential dysbiosis of the maternal and neonatal microbiot a associate d with gestation al diabetes mellitus was investigat ed, and the possible risks of microbial alteration s in the newborns were assessed. It was observed that gestationa l diabetes mellitus may alter the microbio me of both pregnant women and their newborns at birth, shedding light on an alternativ e form of inheritanc e and emphasizi ng the importanc e of understan ding microbio me establish ment in early life. Sevent y-six newbo rns were deliver ed by cesare an sectio n, and sevent een were deliver ed vagina lly. There was no followup contact with the sample reporte d. No limitatio ns were reported. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 786 1 6 Yang Hongli ng Systematic analysis of gut microbiota in pregnant women and its correlations with individual heterogeneit y 20 20 npj Biofilms and Microbi omes China Comprehensive review A total of 1,479 pregna nt wome n partici pated. A total of 1,479 pregna nt wome n partici pated. Stool, urine, and blood samples were collecte d, and a question naire was complet ed. No control group was reporte d The structure and diversity associate d with gestation al age were investigat ed, along with correlatio ns with gut microbio me factors during pregnanc y and microbe– host interactio ns. It was observed that the gut microbio me of pregnant women exhibits an overall structure similar to that of nonpregnant women of comparab le age. A range of exogenou s and endogeno us host factors were found to be strongly associated with variations in the compositi on and function of the intestinal microbial communit y. In The mode of deliver y is not report ed. There was no followup contact with the sample reporte d. Limitatio ns of the present study include the restricte d study design, as each participa nt provided only a single stool sample for analysis, and the fact that the study does not offer any mechanis tic explanati on for the observed variation in host and gut microbio me heteroge neity. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 787 addition, microbial and functional markers were identified that correlated with age, prepregnancy body mass index, residence status, and prepregnancy and gestationa l health conditions . 1 7 Yassou r Moran Strain-Level Analysis of Mother-toChild Bacterial Transmissio n during the First Few Months of Life 20 18 Cell Host and Microbe Finla nd Prospective longitudinal cohort study A total of 44 pregna nt wome n and their newbo rns partici pated. A total of 44 pregna nt wome n and their newbo rns partici pated. Stool samples were collecte d from the mothers and their newbor ns. No control group was reporte d. Cases of bacterial transmiss ion from mother to offspring and the prevalenc e of antibiotic resistanc e genes within each family were Two inheritanc e patterns were observed across multiple species, where the dominant maternal strain is often transmitte d to the infant, but secondary Seven neonat es were born via cesare an sectio n, and thirtyseven were born vagina lly. There was no followup contact with the sample reporte d. No limitatio ns were reported. World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 788 investigat ed. strains occasional ly colonize the infant’s gut. In families where the secondary strain of Bacteroid es uniformis was inherited, the infant harbored a starch utilization gene cluster absent from the mother’s dominant strain, suggestin g a selective advantage of the secondary maternal strain in the infant gut. 1 8 Wenqi ng Yang Ongoing Supplementa tion of Probiotics to 20 21 America n Journal of China Randomized controlled trial A total of 26 neonat es The focus group consist Stool samples were collecte The control group consist The effects of probiotic s on the It was observed that after 28 days of Twent ythree neonat There was no followup Limitatio ns of the present study World Journal of Advanced Research and Reviews, 2025, 27(01), 764-796 795 [20] Nicholson JK, Holmes E, Kinross J, Burcelin R, Gibson G, Jia W, Pettersson S. Host-gut microbiota metabolic interactions. Science. 2012 Jun 8;336(6086):1262-7. doi: 10.1126/science.1223813. [21] Sanidad KZ, Zeng MY. Neonatal gut microbiome and immunity. 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