NRMJ_9_4_238-251

Introduction

Currently, studying the microbiota of the female urogenital tract is one of the most pressing issues for obstetricians, gynecologists, and microbiologists. The cervicovaginal microbiota is of paramount importance in maintaining the physiological processes occurring in the genital tract, as it is a dynamic microenvironment rich in heterogeneous microorganisms, among which bacteria, fungi, viruses, and protozoa are identified (Dong et al., 2023). In obstetric practice, it is especially important to timely identify clinically significant microorganisms, including Streptococcus agalactiae (S. agalactiae), Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), where these microorganisms affect the course of pregnancy and its outcomes. Numerous studies have been conducted, the results of which have established that detection of these microorganisms in the mother is associated with a high percentage of neonatal infections, development of severe infectious complications, and neonatal mortality. Thus, most cases of fatal outcomes, preterm births, and rupture of fetal membranes are specifically associated with infection by the β-hemolytic streptococci (GBS) (Gonçalves et al., 2022; Liu et al., 2022). When this group of microorganisms is detected, as has already been proven, the risk of developing sepsis, severe neonatal meningitis, and neuronal dysfunctions significantly increases, which may subsequently lead to child disability. For these reasons, it is extremely important to conduct screening and perform biomaterial culture tests in the early stages of pregnancy (Melin et al., 2013; Russell et al., 2017; Viqar et al., 2021).

Collection of biomaterials for studying the microbiota of vagina, cervical canal, and urethra is also an important component of a gynecological examination, as this study allowed the physician to make a more accurate diagnosis and, accordingly, prescribe effective therapy. In laboratory services, the most commonly used methods for identifying microorganisms include microscopic, microbiological culture, and molecular genetics. One of the key aspects in research is the pre-analytical stage, as it is the stage that a number of errors are differentiated, including non-compliance with the rules for preparing subjects, errors made by medical personnel during material collection, transportation of biomaterial, and its storage (Schmidt et al., 2015).

By studying the biomaterials (i.e., cervical canal discharge), it is possible to determine the genus of the bacteria using microscopic examination, but it is impossible to determine its species, which leads to difficulties in treatment. In addition, it is also considered impossible to assess the sensitivity of microorganisms to antibiotics, and therefore to prescribe antibiotic therapy. For these reasons, microscopic examination is less effective compared to other methods (Tuyakova et al., 2014; Andreevskaya et al., 2020). Polymerase chain reaction (PCR) is a molecular genetic method that has a number of advantages such as specificity, efficiency, and sensitivity. Moreover, it allows determining the sensitivity of microorganisms to antibiotics, based on the detection of genes responsible for antibiotic resistance (Gygax et al., 2007). An equally important advantage of microbiological research is the ability to assess the sensitivity of microorganisms to antibiotics, which, in turn, significantly increases the effectiveness of treatment. In studying the gynecological smears, all the aforementioned methods have high value; however, each of them has its own advantages and disadvantages (Salam et al., 2023).

In the future, the information obtained will allow us to make predictions about the course of pregnancy and its outcomes, and, based on the presented data, we will be able to assess the condition and development of the fetus depending on the isolation of certain microorganisms. The objectives of this study were to examine patients with the most common obstetric pathology diagnoses, assess the structure of the cervicovaginal tract microbiota, and study its impact on the course of pregnancy.

Materials and Methods

Study design

A retrospective microbiological study was conducted between 2018 and 2022, lasting 5 years. The study was conducted at a hospital specializing in obstetrics and gynecology in collaboration with the microbiological laboratory of Samara State Medical University, Russia. It included two thousand twenty-two women, whose pregnancies were accompanied by disruptions in normal physiological processes, putting them at serious risk of developing complications. The examined patients were divided into four groups. The first group included isthmic-cervical insufficiency requiring maternal medical care, bleeding in early pregnancy, and placental disorders. The second group included preterm labor and delivery. The third group involved singleton delivery, spontaneous delivery, which included clinically healthy women considered as the control group, while the fourth group involved postpartum sepsis patients. Subsequently, the results of the microbiological study were analyzed based on the type of group.

Samples collection

Two thousand twenty two smears of cervical canal discharge were taken from patients by an obstetrician-gynecologist using a swab probe, which was placed in a transport tube containing Ames medium and delivered to the laboratory within 2 hours.

Cultivation of microorganisms

In the microbiology laboratory, each material was inoculated individually onto nutrient agar (NA) and MacConkey agar media (Condalab, Spain), which were intended for the preliminary identification of the microorganisms most commonly detected in the urogenital tract and causing urinary tract infections. 5 % blood agar with defibrinated sheep blood (HiMedia, India) allowed for growth of microorganisms with special cultivation conditions, as well as bacteria with hemolytic activity. Sabouraud agar (HiMedia, India) was used as a selective medium that allowed for detection of growth of yeasts and mold fungi. The inoculated plates were incubated for 48 h at 37 ºC. A CO2 incubator was used to create microaerophilic conditions, preferable for cultivating Lactobacillus and Enterococcus spp. (Kim et al., 2022; Chudzicka-Strugała et al., 2024).

Microbial species identification

The species identification of the grown isolates was carried out using the MALDI-ToF (Matrix Assisted Laser Desorption/Ionization-Time of Flight) mass spectrometry assay with the Microflex LT device (Bruker Daltonik GmbH, Germany). Every type of colonies growing on nutrient media was applied with a tip to the target of the device and subsequently covered with a mixture in the form of α-cyano-4-hydroxycinnamic acid. Afterward, the target was placed in the device, where the bacterial cells were subjected to multiple laser pulse exposures. As a result of this process, the release of ionized ribosomal proteins of the microorganisms occurred, which entered the time of flight analyzer and moved to the detector. The time-of-flight of the particles was evaluated using the instrument’s software, which converted the obtained information into a molecular mass spectrum corresponding to the mass to charge ratio of the particles in the range from 2000 Da to 20000 Da. The mass spectra obtained during the identification process were compared to a library that represented a database with reference spectra. Based on the similarity of proteins and their mass, species identification of the microorganism was achieved. The protein profiles were analyzed using flexAnalysis 3.0 software (Bruker Daltonik GmbH, Germany). A Centroid peak detection algorithm was used to evaluate the obtained mass spectra. The reliability of the identification was determined by using MALDI Biotyper RTC software by calculating the score; if the obtained score was in the range of 0.000 to 1.699, the identification result was considered unreliable; a score from 1.700 to 1.999 indicated high reliability of identification to the genus level; a score from 2.000 to 2.999 was considered highly reliable for species identification. The signal-to-noise threshold was set at level 2. The relative intensity threshold was 0 %, the minimum threshold intensity was 600 arbitrary units, while the maximum number of analyzed peaks was 300. The TopHat method was used to calculate the baseline, and spectrum smoothing was performed using the Savitzky-Golay algorithm with a mass of 5 m/z per cycle. Visualization of the results of statistical proteomic comparison of the obtained mass spectra was carried out using MALDI Biotyper 3.0 Offline Classification software (Bruker Daltonik GmbH, Germany). During this study, the analysis of mass spectra was in accordance with the official recommendations of the manufacturer of the MALDI-ToF mass spectrometer Microflex LT (Bruker Daltonik GmbH, Germany) (Chen et al., 2015, 2023).

Statistical analysis

A statistical analysis was performed using the Pearson’s chi-squared test. Statistical processing of the obtained data was carried out using Microsoft Office Excel 2007. The assessment of the microbiota structure included calculation of the frequency of occurrence of the genus and species affiliation of bacteria and fungi. Numerical results were presented as derivatives and absolute numbers. The results obtained are displayed in the form of diagrams.

Results

General information

Out of the two thousand twenty two swab cultures, microbial growth was detected in 80.2 % of samples, while no growth was observed in 19.8%. A total of 3253 microorganisms were isolated and identified, represented by the following genera: 1056 isolates of Staphylococcus spp. (32.5 %), 709 Enterococcus spp. (21.8 %), 554 Lactobacillus spp. (17.03 %), 400 Candida spp. (12.3 %), 351 Escherichia spp. (10.8 %), 166 Streptococcus spp. (5.10 %), and 17 Enterobacter spp. (0.52 %). The structure of microorganisms isolated during the study period is presented in Figure 1.

Next, the results of microbiological studies were analyzed independently in each group. In the group associated with complications occurring during pregnancy, 953 microorganisms of various genera were detected in the discharge from the cervical canal, among which the predominant representatives were 263 isolates of Staphylococcus spp. (27.6 %). Additionally, 228 isolates of Lactobacillus spp. (23.93 %) were identified as the main symbionts of the cervico-vaginal microbiota. At the same time, 166 isolates of Enterococcus spp. (17.42 %) were isolated, with the most frequently encountered species being E. faecalis and E. faecium. Additionally, 148 isolates of Candida spp. (15.53 %) were obtained. A total of 96 isolates of Escherichia spp. (10.1 %) and 47 isolates of Streptococcus spp. (4.9 %) were detected, among which β-hemolytic streptococci playes a primary role. A minimal identified 5 isolates of Enterobacter spp. (0.53 %) were recovered.

Bleeding in early pregnancy

In women diagnosed with “Bleeding in early pregnancy”, the percentage of Streptococcus. agalactiae was 82.35 % of the total Streptococcus spp., and the share of S. aureus was 3.51 %. In women diagnosed with “Isthmic-cervical insufficiency”, the percentage of Streptococcus agalactiae was 33.33 % of the total Streptococcus spp., while the share of S. aureus was 5.88 %. In patients diagnosed with “Placental disorders”, Streptococcus agalactiae constituted 90 %, and the share of S. aureus was 7.32 %. The species structure of microorganisms identified in this category is presented in Figure 2.

Preterm labor and delivery

In the second category, we selected a cohort of women, including 553 individuals diagnosed with “Preterm labor and delivery”, in whom, 1,116 microorganisms were found on the mucous membrane of the cervical canal. 404 isolates of Staphylococcus spp. were identified in a prevailing amount (36.2 %), with the species diversity of Staphylococcus spp. in this group being more limited compared to the first cohort. The percentage of Staphylococcus aureus was 7.32 %, which significantly exceeds the frequency of detection of similar microorganisms in women diagnosed with “Isthmic-cervical insufficiency requiring medical care for the mother” and “Bleeding in early pregnancy”. Among which, the largest percentage was 213 isolates of S. haemolyticus (39.23 %) and 156 isolates of S. epidermidis (28.73 %). We also identified 234 isolates of Enterococcus spp. (21 %), with E. faecalis being the predominant representative. The symbiotic flora of the cervical microbiota consisted of 170 isolates of Lactobacillus spp. (15.23 %), which is significantly lower in number compared to the previously mentioned genera. A total of 136 isolates of Candida spp. were isolated (12.2 %) and in a practically equivalent amount with a difference of only 2.16 %. 112 isolates of Escherichia spp. (10.04 %) were found. 56 isolates of Streptococcus spp. (5.02 %) were identified, with more than half of these representatives being β-hemolytic streptococci, the majority of which were S. agalactiae and to a significantly lesser extent S. anginosus. In the cohort of examined women with the diagnosis of “Placental disorders”, the percentage of S. agalactiae detection was 90 % out of the total Streptococcus spp. It is worth noting that the smallest proportion was found to be 4 isolates of Enterobacter spp. (0.4 %). In women diagnosed with “Preterm labor and delivery”, the percentage of S. agalactiae was 60.81 % of the total Streptococcus spp., and the share of S. aureus was 6.10 %. The species diversity of microorganisms isolated from women diagnosed with “Preterm labor and delivery” is presented in Figure 3.

Singleton and spontaneous delivery

In this retrospective study, we selected 492 women to study the nature of changes in the cervical canal microbiota in the presence of the diagnosis “Singleton delivery, spontaneous delivery”, in which, 929 microorganisms were identified, and again 305 isolates of Staphylococcus spp. (32.83 %) were identified in a predominant amount. Furthermore, it is noted that the activity of Staphylococcus spp. may be associated with the occurrence of cystitis and urethritis. A total of 232 isolates of Enterococcus spp. were identified (25 %). At the same time, the symbiotic flora consisted of 147 isolates of Lactobacillus spp. (15.82 %). In addition, 109 isolates of Candida spp. (11.73 %), 89 isolates of Escherichia spp. (9.6 %), and 42 isolates of Streptococcus spp. (4.52 %) were detected with significant species heterogeneity, among which the conditionally pathogenic flora was less pronounced. Less numerous species diversity was observed in Enterobacter spp. (0.54 %), among which only 5 isolates were isolated. In women diagnosed with “Single spontaneous delivery”, the percentage of S. agalactiae was 54.80 % of the total Streptococcus spp., and the share of S. aureus was 4.6 %. The species structure of microorganisms isolated from women diagnosed with “single fetus delivery, spontaneous delivery” is presented in Figure 4.

Postpartum sepsis

The greatest interest is in the fourth group diagnosed with “Postpartum sepsis. The number of women studied with this pathology was 158, and 255 microorganisms were isolated from the mucous membranes of the cervical canal, among which the predominant representatives were 84 isolates of Staphylococcus spp. (32.9 %) and 77 isolates of Enterococcus spp. (30.2 %). However, in women diagnosed with “Postpartum sepsis”, the frequency of S. aureus occurrence was 27.3 %, which was 4-6 times higher compared to the other cohorts. 54 isolates of Escherichia spp. (21.2 %) and 21 isolates of Streptococcus spp. (8.24 %) were detected, of which 81 % were β-hemolytic streptococci. In this cohort, the amount of symbiotic flora was sharply reduced and amounted to only 9 isolates of Lactobacillus spp. (3.53 %), which indicates a high degree of colonization of the cervical canal by the pathogenic microorganisms. In the studied biomaterial, 7 isolates of Candida spp. (2.8 %) and 3 isolates of Enterobacter spp. (1.2 %) were identified. In women diagnosed with “Postpartum sepsis”, the percentage of S. agalactiae was 66.70 % of the total Streptococcus spp., and the share of S. aureus was 27.38 %. The species structure of the qualitative and quantitative composition of the cervical canal microbiota isolated from women diagnosed with “Postpartum sepsis” is presented in Figure 5.

The species diversity of the genus Lactobacillus spp. is presented in Figure 6.

Discussion

In the practical part of this research work, we used a highly sensitive research method that allowed for the isolation of even a small number of microorganisms contained in the biomaterial. The specificity of this method was based on the use of selective nutrient media to ensure the growth of microorganisms in accordance with their biological needs and metabolic activity. Identification of the bacteria and fungi was carried out using the highly informative MALDI-TOF mass spectrometry method, which is the “gold standard” that allows for the determination of the protein profile of microorganisms; ensuring reliable identification of the species structure of bacteria and fungi in a short time. The results of this study largely depended on a pre-analytical stage of the study: collection, transportation, and storage duration of the biomaterial. Another limitation is the duration of classical cultivation, which took 48 h. The MALDI-TOF mass spectrometry method has become the “gold standard” in many countries; however, it remains inaccessible due to being expensive equipment. The obtained results allowed us to trace the relationship between the dominant microbiota of women and obstetric pathologies, which can be used in practice to predict the course of pregnancy. It is also worth noting how important it is to maintain communication between the microbiologist and the obstetrician-gynecologist, as competent interpretation of microbiological study results allows for prescription of effective therapy and significantly improves the condition of the patients.

In this study, the cohort of women was divided into four groups: patients with complications occurring during pregnancy, patients with a history of pathological preliminary period, patients with a normal course of pregnancy, and patients with sepsis. But the greatest interest is in the fourth group diagnosed with “Postpartum sepsis”, due to the fact that the number of pathogens causing severe urogenital infections significantly exceeds the number of symbiotic bacteria. In each of these groups, Staphylococcus spp. were predominantly isolated, among which S. epidermidis and S. haemolyticus were most frequently identified. Representatives of this genus belong to the conditionally pathogenic flora that is normally present in smears taken from the vagina and cervical canal. In the case of the development of immunodeficiency states and decreased body reactivity, the conditionally pathogenic flora becomes pathogenic. In 2018, a study was conducted at the Research Institute of Obstetrics, Gynecology, and Reproductology, which found that women with a history of early preterm births and had a high risk of pregnancy loss had a microbiota that was more associated with the order Enterobacterales, including Staphylococcus spp. and Streptococcus spp. (Sinyakova et al., 2018). In this study, women diagnosed with “Preterm labor and delivery” had 404 isolates of Staphylococcus spp. (36.2 %) that were also isolated in a prevailing amount, among which the largest percentage was 213 isolates of S. haemolyticus (39.23 %) and 156 isolates of S. epidermidis (28.73%). Among the order Enterobacterales, 112 isolates of Escherichia spp. (10.04 %) were most frequently isolated, in addition to 56 isolates of Streptococcus spp. (5.02 %), which correlates with a previously obtained data (Golińska et al., 2023). The negative impact on the pregnancy course by conditionally pathogenic microorganisms begins to manifest actively in cases of reduced vaginal symbionts, i.e., Lactobacillus spp., which is accompanied by a significant increase in vaginal pH and rapid colonization of the mucous membrane of the urogenital tract by the conditionally pathogenic and non-pathogenic microorganisms (Krawczyk et al., 2021). Subsequently, the bacteria overcome the placental barrier and have entered the fetal membranes, infecting them and causing the development of chorioamnionitis, which later has threatened the pregnancy termination (Bianchi-Jassir et al., 2017). In women diagnosed with ”Singleton delivery, spontaneous delivery”, similar microorganisms were isolated in predominant quantities: 305 isolates of Staphylococcus spp. (32.83 %), 89 isolates of Escherichia spp. (9.6 %), and 42 isolates of Streptococcus spp. (4.52 %), but the pregnancy proceeded without the risk of associated complications, which raises a controversial question about the clinical importance and significance of the role of Staphylococcus spp. in obstetric and gynecological practice. According to the obtained results of the “Belgorod State National Research University”, in women whose postpartum period was complicated by the development of endometritis, S. epidermidis was isolated twice as often compared to the control group (Brown et al., 2019). Thus, at different time intervals, the fundamental significance of Staphylococcus spp. has been repeatedly proven empirically both in pregnancy outcomes and postpartum period. Having analyzed the microbiota of the vagina in women with the previously mentioned diagnoses, we found that Staphylococcus spp. was detected somewhat more frequently compared to Streptococcus spp., and this genus of bacteria is of a particular clinical interest (Bodaszewska et al., 2010; Rosini and Margarit, 2015). The most frequently isolated microorganism among Streptococcus spp. was S. agalactiae. This bacterial sp. is a β-hemolytic (GBS), and catalase-negative facultative anaerobe. Numerous studies have been conducted on the relationship between GBS colonization of the mucous membranes of the urogenital tract and its impact on the course of pregnancy (Armistead et al., 2019; Raabe and Shane, 2019; Yuan et al., 2021). Thus, according to the results of our study, 45 isolates of S. agalactiae were isolated from women diagnosed with “Preterm labor and delivery”, which constituted 60.81 % of all the isolated Streptococcus spp. Possible pathogenetic mechanisms are closely related to changes in the microbiological landscape of the vaginal microbiota and the rapidly developing ascending infection through the cervix, which subsequently leads to the infection of the fetal and decidual membranes (Olmos-Ortiz et al., 2022; Liu et al., 2023). Once inside, GBS begin to actively produce proteases contained in membrane vesicles, which lead to collagen degradation, destruction of the cellular framework, and the extracellular matrix of the fetal membranes. In addition, the inflammatory process is activated with the synthesis of cytokines and prostaglandins, as a result of which the uterus begins to contract actively, which may lead to premature birth, rupture of the fetal membranes, and subsequent spread of infection through the bloodstream of the mother and child, increasing the risk of developing sepsis (Yamamoto et al., 2005; Valkenburg-van den Berg et al., 2009). Timely detection of S. agalactiae is of high value in obstetric and gynecological practice, as this pathogen, colonizing the mucous membrane of the vagina, does not cause clinical symptoms, which complicates the timely identification of this microorganism (Coggins et al., 2024). S. agalactiae progressively modifies, leading to the development of new highly virulent adaptation mechanisms that enhance the survival of microbial strains in the human body. Thus, bacteria with the adhesin HvgA and laminin-binding protein (lmb) on their surface pose the greatest danger, as they can attach to endothelial cells of the vessels involved in the formation of the blood-brain barrier (BBB), thereby increasing the risk of S. agalactiae penetrating the brain’s vessels, which subsequently provokes the development of meningitis (Landwehr-Kenzel et al., 2014). GBS also produces a hemolytic pigment, which poses the greatest danger to the fetus, as it reduces the barrier function of the amniotic epithelium and the placental barrier (Armistead et al., 2021). By penetrating the amniotic fluid and infecting it, the likelihood of bacterial invasion into the lungs as a result of aspiration increases, which may subsequently lead to the development of pneumonia (Sharma et al., 2013). Enterococcus spp. are Gram (+) aerobic cocci that colonize the digestive tract (Daca et al., 2024). The most common representatives of Enterococcus spp. are E. faecalis and E. faecium, which are commensal microorganisms of the intestinal microbiota (Golob et al., 2019). Enterococcus spp. are closely associated with several processes occurring in the intestinal microbiome, as they contribute to activation of cellular and humoral immunity, modulate the immune response, and participate in maintaining intestinal homeostasis, through stabilizing the pH environment, synthesizing vitamins, and suppressing the active reproduction of putrefactive bacteria (Madani et al., 2024). However, when the barrier function of the intestinal mucosa is weakened, E. faecalis and E. faecium are capable of migrating into the bloodstream, causing the development of bacteremia, which can subsequently lead to infection of other organs and tissues, thereby increasing the risk of serious complications. Most often, Enterococcus spp. colonize the epithelium of the mucous membranes of the urinary tract and vagina, entering these tissues with the bloodstream, in addition to the anatomical features of the female urogenital system (Banla et al., 2019). According to the obtained results of this study, the percentage of Enterococcus spp. was 21.80 % and Lactobacillus spp. was 17.03 %. The presence of Enterococcus spp. in the biomaterial of the subjects may often indicate existing inflammatory processes in the genitourinary tract. Among the symbionts of the internal environment, Lactobacillus spp. play a key role via colonizing the epithelium of the vagina through the interaction between the surface charges of the host cells and the bacteria. The adhesion process of Lactobacillus spp. to the epithelial cells correlates with the level of estrogen in the blood (Tachedjian et al., 2017). Deviation of this indicator from the normal causes a change in the charge of the host cells and modification of the properties of the bacteria, which, in turn, affects the composition of the microflora and, consequently, the pH levels (Redondo-Lopez et al., 1990). It should be noted that a significant feature of these bacteria is their ability to metabolize cellular glycogen into glucose, and then into lactic acid, thereby maintaining the optimal acidity of the vagina, which is within the pH range of 3.5-4.5 (Stojanović et al., 2012; Chee et al., 2020). Also, Lactobacillus spp. are capable of producing hydrogen peroxide and bacteriocins, which by their biochemical nature are thermostable proteins capable of exerting a destructive effect on the cytoplasmic membrane of both Gram (+) and Gram (-) bacteria, as well as breaking down the murein, which is part of their cell wall (Ocaña et al., 1999; Gaspar et al., 2018). Lactobacillus spp. play a significant role in preventing colonization of the vaginal mucosa by the pathogenic microorganisms and in maintaining the normal microbiological landscape of the cervico-vaginal tract. At the same time, a decrease in the symbiotic flora represented by Lactobacillus spp. may indicate a decrease in the protective properties of the cervical microbiota and an increased likelihood of colonization of the mucous membranes by the pathogenic microorganisms (Liu et al., 2023). Pathogens also suppress activity of the bacteria that produce the main protective substance, i.e., lactic acid, which subsequently significantly alters the pH level and reduces the barrier function of the epithelial mucosa of the vagina (Mendling, 2016; Saraf et al., 2021). The results of several previous studies revealed the ability of E. coli and E. faecalis not only to form highly structured vaginal biofilms but also to penetrate biofilms formed by Gardnerella vaginalis (G. vaginalis) (Castro et al., 2016; Reuschel et al., 2020). Such a pathogenicity factor allows E. coli and E. faecalis to persist in the vagina for a prolonged period and subsequently migrate to the upper sections of the urogenital tract, causing the development of urinary tract infections. In E. coli, this is mediated via the synthesis of an antigen responsible for inter bacterial interaction, while in E. faecalis, it is conducted through the ability to produce a protein by which co-aggregation with other bacteria of the vaginal micro-ecosystem may occur (Javed and Manzoor, 2020; Jahic, 2022). For pregnant women, episodes of significant changes in the microbiological landscape may be fatal, leading to rupture of the fetal membranes, infection of the fetus, and death of the newborn (Brokaw et al., 2021). By analyzing the vaginal microbiota in women whose pregnancies were accompanied by the development of pathological processes and women with a normal gestational period, we observed a significant decrease in the concentration of Lactobacillus spp. with a simultaneous increase in the amount of Enterococcus spp. This indicates a high degree of dependence on epithelial colonization of the vagina between symbiotic bacteria and uropathogens. In women with normal pregnancy progression, the abundance of Lactobacillus spp. was somewhat lower compared to Enterococcus spp., but no serious complications were observed during pregnancy or at the postpartum period, suggesting that the pathogenic activity of these bacteria is associated with the presence of urinary tract infections and severe dysbiotic disorders (Sharon et al., 2023).

Conclusions and Recommendations

Upon assessing the microbiological landscape and comparing it with the diagnosis of patients, it was found that significant changes in the cervical canal microbiota lead to serious consequences and complications for the mother’s body. In the future, it would be interesting to conduct multiple studies to compare microbiological results with other obstetric pathologies and identify the effect of cervicovaginal microbiota on the condition of newborns. E. faecalis, C. albicans, S. agalactiae, S. aureus, and S. anginosus are of fundamental clinical importance. That is why it is extremely important for obstetricians-gynecologists and microbiologists to assess the composition of the cervical canal microbiota in women during gestation. This study involves data that can help the physicians predict the course of pregnancy, and determine the risks and the possible adverse outcomes.

Acknowledgements

We would like to express our gratitude to the Rector and Vice-Rector for Research of Samara State Medical University for their support.

Novelty Statement

The novelty of the study lies in the established pattern between the processes and various obstetric pathologies, which in the future will allow for the advance prediction of the course of pregnancy and possible outcomes for both the mother and the fetus.

Author’s Contribution

Conceptualization: AVK, AAA, AVY and IAB

Conducting the study: AAA and IAB

Analysis of results: AVK and IAB

Literature search: AVK, AAA, AVY and IAB

Article preparation: AVK, AAA, AVY and IAB

Review writing and editing: AVK, AAA

Ethical approval

The study design was approved by the local Ethics Committee on Bioethics of the Federal State Budgetary Educational Institution of Higher Education «Samara State Medical University» of the Ministry of Healthcare of the Russian Federation (FSBEI HE SamSMU MOH Russia), protocol No. 242 dated November 23, 2022. Written consents of the participants were provided.

Funding source

This work was not funded by any source.

Conflict of interests

The authors have declared no conflicts of interest.

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