The vaginal microbiota demonstrates its important role in the reproductive age women’s health or disease. Many studies show that
The aim of this study was to assess the prevalence of
The clinical signs divide the patients into symptomatic and asymptomatic groups. The group of symptomatic women included those who reported at least one symptom in the genital tract: itching, burning, discharge, pain, or discomfort. The asymptomatic group reported no such complaints.
Swabs were taken from the posterior vaginal vault and endocervical canal using a sterile speculum. The vaginal content remaining on the speculum was used to measure the pH value using pH indicator strips with a pH range of 2.0–9.0 (MERCK, Germany). One vaginal swab was used for Gram staining with PREVI® Color Gram stainer (bioMerieux, France). The vaginal Gram stain smears were assessed using the scale according to Kuczyńska modified by Kasprowicz (Kasprowicz and Białecka 2012). The presence of leukocytes, lactobacilli, other bacteria, fungi, and clue cells was assessed based on an abundance scale ranging from 0 to 3 in oil-immersion microscope fields (× 1000). The degrees III, III/IV, and IV with clue cells detected indicated BV, which is comparable to a score from 7 to 10 according to Nugent criteria (Nugent et al. 1991; Kuczyńska 2003; Kasprowicz and Białecka, 2008). The specimen from the first vaginal swab was also inoculated in Trichomedium (GRASO, Poland). After 48 hours of culture, a direct preparation was made and viewed under a microscope (200 × magnification) to identify
The second vaginal swab was used to perform cultures on TSA with 5% sheep blood (GRASO, Poland) for the detection of aerobic bacteria, Gardnerella Agar (bio-Merieux, France) for anaerobic bacteria, CANDIselect (BioRad, USA) for yeasts, and Chocolate Agar + P.V.S. + VCAT (BioRad, USA) for
Material collected from the cervical swabs was preserved on UTM medium (Copan Italia, Italy) and tested for
Among 1,155 women,
The prevalence of specific microorganisms across groups of women manifesting or not clinical symptoms.
Microorganisms | Microbiological method | Total | Without symptoms (n = 756) | With symptoms (n = 399) | OR*** (95% CI) | ||
---|---|---|---|---|---|---|---|
n (%) | n (%) | n (%) | |||||
microscopic | 1,107 (95.8) | 737 (97.5) | 370 (92.7) | < 0.001 | 0.33 |
< 0.001 | |
microscopic, culture | 56 (4.8) | 11 (1.5) | 45 (11.3) | < 0.001 | 8.32 |
< 0.001 | |
PCR | 276 (23.9) | 108 (14.3) | 166 (41.6) | < 0.001 | 4.26 |
< 0.001 | |
PCR | 187 (16.2) | 81 (10.7) | 106 (26.6) | < 0.001 | 3.01 |
< 0.001 | |
PCR | 89 (7.7) | 27 (3.6) | 62 (15.5) | < 0.001 | 4.91 |
< 0.001 | |
PCR | 21 (1.8) | 0 (0.0) | 21 (5.3) | < 0.001# | 85.94 |
0.002 | |
PCR | 2 (0.2) | 0 (0.0) | 2 (0.5) | 0.119# | 9.62 |
0.146 | |
PCR | 8 (0.7) | 1 (0.1) | 7 (1.8) | 0.003# | 9.62 |
0.012 | |
Aerobic bacteria (with GBS) | culture | 153 (13.2) | 95 (12.6) | 58 (14.5) | 0.396 | 1.19 |
0.339 |
culture | 88 (7.6) | 57 (7.5) | 31 (7.8) | 0.981 | 1.04 |
0.865 | |
Yeast | microscopic, culture | 192 (16.6) | 100 (13.2) | 92 (23.1) | < 0.001 | 1.97 |
< 0.001 |
culture | – | – | – | – | – | ||
culture | – | – | – | – | – |
* – all
** –
*** – OR of prevalence symptoms in women with specific microorganisms detected when compared with those without symptoms
The occurrence of urogenital mycoplasmas (
Fig. 1
The prevalence of mycoplasmas and

Univariable analysis showed that women in whom
Association between the prevalence of microorganisms and clinical symptoms – multivariable analyses. The fully adjusted model and the most parsimonious model.
Microorganisms | Model 1* | Model 2** | ||
---|---|---|---|---|
OR*** (95% CI) | OR*** (95% CI) | |||
3.06 |
< 0.001 | 3.07 |
< 0.001 | |
5.25 |
< 0.001 | 5.20 |
< 0.001 | |
49.30 |
0.006 | 48.97 |
0.007 | |
10.03 |
0.012 | 10.04 |
0.012 | |
0.47 |
0.045 | 0.48 |
0.033 | |
3.92 |
< 0.001 | 3.87 |
< 0.001 | |
Yeast | 1.73 |
0.002 | 1.73 |
0.002 |
DF | 12 | 7 | ||
AICc | 207.5 | 197.8 | ||
ΔAICc | 9.7 | 0.0 |
* – Model 1 – a fully adjusted model to variables presented in Table II and additionally to
** – Model 1 – the most parsimonious model adjusted to variables presented in Table II
*** – OR of prevalence symptoms in women with detected specific microorganisms compared with those without symptoms
Multivariable analysis found the vaginal colonization by
Relationship between the presence of
Microorganisms | Without |
With |
OR*** (95% CI) | ||
---|---|---|---|---|---|
n (%) | n (%) | ||||
930 (9 6.1) | 177 (9 4.7) | 0.489 | 0.72 |
0.372 | |
32 (3 .3) | 24 (1 2.8) | < 0.001 | 4.30 |
< 0.001 | |
5 (0.5) | 3 (1.6) | 0.125# | 2.60 |
0.101 | |
14 (1.4) | 7 (3.7) | 0.064# | 2.65 |
0.0313 | |
2 (0.2) | 0 (0.0) | 1.000# | 0.00 |
0.534 | |
87 (9 .0) | 2 (1 .1) | < 0.001 | 0.11 |
< 0.001 | |
Aerobic bacteria | 134 (1 3.8) | 19 (1 0.2) | 0.214 | 0.70 |
0.174 |
Yeast | 150 (1 5.5) | 42 (2 2.5) | 0.025 | 1.58 |
0.019 |
82 (8 .5) | 6 (3 .2) | 0.020 | 0.36 |
0.017 |
*
** –
*** – OR of prevalence of specific microorganisms in women with
Among the 187 women with positive
Relationship between the presence of
Microorganisms | Without |
With |
OR*** (95% CI) | ||
---|---|---|---|---|---|
n (%) | n (%) | ||||
1,024 (96.1) | 83 (9 3.3) | 0.319 | 0.57 |
0.203 | |
43 (4 .0) | 13 (1 4.6) | < 0.001 | 4.07 |
< 0.001 | |
8 (0.8) | 0 (0.0) | 1.000# | 0.00 |
0.412 | |
13 (1.2) | 8 (9.0) | < 0.001# | 8 |
< 0.001 | |
1 (0.1) | 1 (1.1) | 0.148# | 5.98 |
0.025 | |
185 (1 7.4) | 2 (2 .2) | < 0.001 | 0.11 |
< 0.001 | |
Aerobic bacteria | 137 (1 2.9) | 16 (1 8.0) | 0.227 | 1.48 |
0.171 |
Yeast | 173 (1 6.2) | 19 (2 1.3) | 0.272 | 1.40 |
0.213 |
77 (7 .2) | 11 (1 2.4) | 0.122 | 1.81 |
0.083 |
* – all
** –
*** – OR of prevalence specific microorganisms in women with
Among 89 women with positive
Relationship between the detection of
pH ≤ 4.5 n (%) | pH > 4.5 n (%) | OR*** (95% CI) | ||
---|---|---|---|---|
180 (1 5.6%) | 94 (8 .1%) | 2.1 |
< 0.005 | |
173 (15.7%) | 65 (5.9%) | 1.60 |
0.004 |
** –
*** – OR of prevalence pH > 4.5 in women with
Distribution of vaginal pH values in women with and without the presence of specific microorganisms.
Microorganisms | Not prevalent | Prevalent | pH > 4.5 OR (95% CI)** | ||||
---|---|---|---|---|---|---|---|
n | Q2 (Q1-Q3) | n | Q2 (Q1-Q3) | ||||
48 | 5.5 (5.0–5.5) | 1,107 | 4.5 (4.0–4.5) | < 0.001 | 0.01 (0.00–0.05) | < 0.001 | |
1,099 | 4.5 (4.0–4.5) | 56 | 5.0 (4.9–5.5) | < 0.001 | 11.18 (6.05–20.65) | < 0.001 | |
881 | 4.5 (4.0–4.5) | 274 | 4.5 (4.5–5.0) | < 0.001 | 2.09 (1.55–2.82) | < 0.001 | |
968 | 4.5 (4.0–4.5) | 187 | 4.5 (4.5–5.0) | 0.001 | 1.71 (1.21–2.41) | 0.002 | |
1,066 | 4.5 (4.0–4.5) | 89 | 4.5 (4.5–5.0) | 0.004 | 2.42 (1.55–3.78) | < 0.001 | |
1,134 | 4.5 (4.0–4.5) | 21 | 4.5 (4.5–5.0) | 0.008 | 3.07 (1.31–7.16) | 0.010 | |
Aerobic bacteria (with GBS) | 1,002 | 4.5 (4.0–4.5) | 153 | 5.0 (4.5–5.0) | < 0.001 | 7.44 (5.17–10.69) | < 0.001 |
1,067 | 4.5 (4.0–4.5) | 88 | 5.0 (4.5–5.1) | < 0.001 | 5.89 (3.76–9.24) | < 0.001 | |
Yeast | 963 | 4.5 (4.0–4.5) | 192 | 4.5 (4.5–5.0) | 0.003 | 1.49 (1.06–2.10) | 0.023 |
* – based on Mann-Whitney
** – based on logistic regression, crude models, Firth method, OR of prevalence pH > 4.5 in women with specific microorganisms compared with those without their presence Q2 (Q1-Q3) – median (interquartile range)
Association between the prevalence of microorganisms and pH > 4.5 – multivariable analyses.
The fully adjusted model and the most parsimonious model.
Microorganisms | Model 1* | Model 2** | ||
---|---|---|---|---|
OR (95% CI) | OR (95% CI) | |||
1.81 (1.21–2.73) | 0.004 | 1.86 (1.24–2.79) | 0.003 | |
2.23 (1.31–3.78) | 0.003 | 2.32 (1.37–3.92) | 0.002 | |
0.03 (0.01–0.11) | < 0.001 | 0.03 (0.01–0.11) | < 0.001 | |
5.91 (2.91–12.00) | < 0.001 | 6.54 (3.25–13.18) | < 0.001 | |
Aerobic bacteria (with GBS) | 7.31 (4.14–12.91) | < 0.001 | 6.85 (4.61–10.18) | < 0.001 |
DF | 11 | 5 | ||
AICc | 287.7 | 275.0 | ||
ΔAICc | 12.7 | 0.0 |
* – Model 1 – fully adjusted model variables presented in the Table and additionally to yeast, Streptococcus group B,
** – Model 2 – the most parsimonious model, adjusted to variables presented in the Table; OR of prevalence pH > 4.5
*** –
Fig. 2
Distribution of vaginal pH values in women with and without the presence of specific microorganisms. Dots denote extreme values; vertical segments are placed at median values, and boxes are located at quartile values. All differences in pH levels between groups were statistically significant.

According to our data, a higher pH value (pH > 4.5) increases the chance of
This presented retrospective study showed a set of results from women in reproductive age diagnosed at the Microbiology and Autovaccine Research Center in Cracow, Poland. Gynecologists referred patients participating in the study to the laboratory for preventive or diagnostic examinations in case of suspected infection in the genital tract. The relationship between the presence of specific microorganisms and the manifestation of various symptoms was investigated. The significant positive associations between vaginal infection of
Among 1,155 women in our study, 24,2% were colonized by single or multiple species of genital mycoplasmas. Most patients (23.02%) presented single mycoplasma species versus infrequent double and triple colonization, which was detected only in 1.2% of women. The other observational study conducted on a group of 1,761 women showed a much higher general prevalence of mycoplasmas (56.4%). In 39.4% of patients, single species colonization was detected (Leli el al. 2018). Contrary to our results, no association between
The study shows that women with
Several observational studies have shown that BV and undetectable vaginal lactobacilli are important risk factors for STIs, such as HIV (Martin et al. 1999) and HPV infections (Watts et al. 2005; Biernat-Sudolska et al. 2011). BV microbiota assessed by Gram staining is associated with a significantly increased risk for acquisition of
Excessive growth of
Our many years of experience in microbial diagnostics were starting points for retrospective analysis of microorganisms’ prevalence, including urogenital mycoplasmas, in the south Poland population of women. The paper is retrospective, based on patients’ charts who underwent routine microbiological diagnosis of the genital tract and answered questions regarding symptoms and antibiotic treatment and medical referrals. The paper attempts to use a large pool of data on the microbiota of the genital tract in a population of women in the south of Poland. Information on the prevalence of specific etiological factors of reproductive tract infections could be valuable for clinics. As a part of routine work, our diagnostic laboratory of the CBMiA carries out diagnostics of the reproductive tract, including microscopic technique, microbial culture technique, and molecular methods (NAAT).
Infections of
The strength of our study is the numerous patient group and the broad picture of microorganisms that have been investigated. On the other hand, the impact of microbiota on women’s health and often co-infections certainly cannot be solved by methods used in routine microbiological diagnostics. The diversity of the vaginal microbiota requires further studies with high-throughput sequencing. However, classic diagnostic microbiology can still broaden the knowledge of the microorganism prevalence in the genital tract and support women’s reproductive health.
In addition, the group of women with symptoms was smaller than the asymptomatic group. It is mainly because of the retrospective character of the analysis and the chosen exclusions parameters. Some women who reported symptoms were not tested with all three microbiological methods; microscopy, culture, and NAAT, and, therefore, were excluded from the analysis. In some cases of STI risk, only NAAT was proceed according to the physician’s prescription. Also, when candidiasis or BV were suspected, only microscopic evaluation of vaginal smear and culture were conducted along with the gynecologist’s recommendation. In our opinion, the picture of coinfections needs more attention from physicians, diagnosticians, and scientists. Future studies should include more numerous groups of women with particular attention to symptoms. The symptoms assessment is an important factor in the analysis. It may result in bias since not every woman experiences the symptoms to the same degree, and many factors can influence this assessment.
In conclusion, a relationship between colonization of the female genital tract by
Fig. 1

Fig. 2

Relationship between the presence of U. urealyticum and other microorganisms.
Microorganisms | Without |
With |
OR*** (95% CI) | ||
---|---|---|---|---|---|
n (%) | n (%) | ||||
1,024 (96.1) | 83 (9 3.3) | 0.319 | 0.57 |
0.203 | |
43 (4 .0) | 13 (1 4.6) | < 0.001 | 4.07 |
< 0.001 | |
8 (0.8) | 0 (0.0) | 1.000# | 0.00 |
0.412 | |
13 (1.2) | 8 (9.0) | < 0.001# | 8 |
< 0.001 | |
1 (0.1) | 1 (1.1) | 0.148# | 5.98 |
0.025 | |
185 (1 7.4) | 2 (2 .2) | < 0.001 | 0.11 |
< 0.001 | |
Aerobic bacteria | 137 (1 2.9) | 16 (1 8.0) | 0.227 | 1.48 |
0.171 |
Yeast | 173 (1 6.2) | 19 (2 1.3) | 0.272 | 1.40 |
0.213 |
77 (7 .2) | 11 (1 2.4) | 0.122 | 1.81 |
0.083 |
Association between the prevalence of microorganisms and clinical symptoms – multivariable analyses. The fully adjusted model and the most parsimonious model.
Microorganisms | Model 1* | Model 2** | ||
---|---|---|---|---|
OR*** (95% CI) | OR*** (95% CI) | |||
3.06 |
< 0.001 | 3.07 |
< 0.001 | |
5.25 |
< 0.001 | 5.20 |
< 0.001 | |
49.30 |
0.006 | 48.97 |
0.007 | |
10.03 |
0.012 | 10.04 |
0.012 | |
0.47 |
0.045 | 0.48 |
0.033 | |
3.92 |
< 0.001 | 3.87 |
< 0.001 | |
Yeast | 1.73 |
0.002 | 1.73 |
0.002 |
DF | 12 | 7 | ||
AICc | 207.5 | 197.8 | ||
ΔAICc | 9.7 | 0.0 |
The prevalence of specific microorganisms across groups of women manifesting or not clinical symptoms.
Microorganisms | Microbiological method | Total | Without symptoms (n = 756) | With symptoms (n = 399) | OR*** (95% CI) | ||
---|---|---|---|---|---|---|---|
n (%) | n (%) | n (%) | |||||
microscopic | 1,107 (95.8) | 737 (97.5) | 370 (92.7) | < 0.001 | 0.33 |
< 0.001 | |
microscopic, culture | 56 (4.8) | 11 (1.5) | 45 (11.3) | < 0.001 | 8.32 |
< 0.001 | |
PCR | 276 (23.9) | 108 (14.3) | 166 (41.6) | < 0.001 | 4.26 |
< 0.001 | |
PCR | 187 (16.2) | 81 (10.7) | 106 (26.6) | < 0.001 | 3.01 |
< 0.001 | |
PCR | 89 (7.7) | 27 (3.6) | 62 (15.5) | < 0.001 | 4.91 |
< 0.001 | |
PCR | 21 (1.8) | 0 (0.0) | 21 (5.3) | < 0.001# | 85.94 |
0.002 | |
PCR | 2 (0.2) | 0 (0.0) | 2 (0.5) | 0.119# | 9.62 |
0.146 | |
PCR | 8 (0.7) | 1 (0.1) | 7 (1.8) | 0.003# | 9.62 |
0.012 | |
Aerobic bacteria (with GBS) | culture | 153 (13.2) | 95 (12.6) | 58 (14.5) | 0.396 | 1.19 |
0.339 |
culture | 88 (7.6) | 57 (7.5) | 31 (7.8) | 0.981 | 1.04 |
0.865 | |
Yeast | microscopic, culture | 192 (16.6) | 100 (13.2) | 92 (23.1) | < 0.001 | 1.97 |
< 0.001 |
culture | – | – | – | – | – | ||
culture | – | – | – | – | – |
Relationship between the detection of Ureaplasma spp. and pH > 4.5 regarding Gardnerella vaginalis coinfections.
pH ≤ 4.5 n (%) | pH > 4.5 n (%) | OR*** (95% CI) | ||
---|---|---|---|---|
180 (1 5.6%) | 94 (8 .1%) | 2.1 |
< 0.005 | |
173 (15.7%) | 65 (5.9%) | 1.60 |
0.004 |
Distribution of vaginal pH values in women with and without the presence of specific microorganisms.
Microorganisms | Not prevalent | Prevalent | pH > 4.5 OR (95% CI)** | ||||
---|---|---|---|---|---|---|---|
n | Q2 (Q1-Q3) | n | Q2 (Q1-Q3) | ||||
48 | 5.5 (5.0–5.5) | 1,107 | 4.5 (4.0–4.5) | < 0.001 | 0.01 (0.00–0.05) | < 0.001 | |
1,099 | 4.5 (4.0–4.5) | 56 | 5.0 (4.9–5.5) | < 0.001 | 11.18 (6.05–20.65) | < 0.001 | |
881 | 4.5 (4.0–4.5) | 274 | 4.5 (4.5–5.0) | < 0.001 | 2.09 (1.55–2.82) | < 0.001 | |
968 | 4.5 (4.0–4.5) | 187 | 4.5 (4.5–5.0) | 0.001 | 1.71 (1.21–2.41) | 0.002 | |
1,066 | 4.5 (4.0–4.5) | 89 | 4.5 (4.5–5.0) | 0.004 | 2.42 (1.55–3.78) | < 0.001 | |
1,134 | 4.5 (4.0–4.5) | 21 | 4.5 (4.5–5.0) | 0.008 | 3.07 (1.31–7.16) | 0.010 | |
Aerobic bacteria (with GBS) | 1,002 | 4.5 (4.0–4.5) | 153 | 5.0 (4.5–5.0) | < 0.001 | 7.44 (5.17–10.69) | < 0.001 |
1,067 | 4.5 (4.0–4.5) | 88 | 5.0 (4.5–5.1) | < 0.001 | 5.89 (3.76–9.24) | < 0.001 | |
Yeast | 963 | 4.5 (4.0–4.5) | 192 | 4.5 (4.5–5.0) | 0.003 | 1.49 (1.06–2.10) | 0.023 |
Relationship between the presence of U. parvum and other microorganisms.
Microorganisms | Without |
With |
OR*** (95% CI) | ||
---|---|---|---|---|---|
n (%) | n (%) | ||||
930 (9 6.1) | 177 (9 4.7) | 0.489 | 0.72 |
0.372 | |
32 (3 .3) | 24 (1 2.8) | < 0.001 | 4.30 |
< 0.001 | |
5 (0.5) | 3 (1.6) | 0.125# | 2.60 |
0.101 | |
14 (1.4) | 7 (3.7) | 0.064# | 2.65 |
0.0313 | |
2 (0.2) | 0 (0.0) | 1.000# | 0.00 |
0.534 | |
87 (9 .0) | 2 (1 .1) | < 0.001 | 0.11 |
< 0.001 | |
Aerobic bacteria | 134 (1 3.8) | 19 (1 0.2) | 0.214 | 0.70 |
0.174 |
Yeast | 150 (1 5.5) | 42 (2 2.5) | 0.025 | 1.58 |
0.019 |
82 (8 .5) | 6 (3 .2) | 0.020 | 0.36 |
0.017 |
Association between the prevalence of microorganisms and pH > 4.5 – multivariable analyses. The fully adjusted model and the most parsimonious model.
Microorganisms | Model 1* | Model 2** | ||
---|---|---|---|---|
OR (95% CI) | OR (95% CI) | |||
1.81 (1.21–2.73) | 0.004 | 1.86 (1.24–2.79) | 0.003 | |
2.23 (1.31–3.78) | 0.003 | 2.32 (1.37–3.92) | 0.002 | |
0.03 (0.01–0.11) | < 0.001 | 0.03 (0.01–0.11) | < 0.001 | |
5.91 (2.91–12.00) | < 0.001 | 6.54 (3.25–13.18) | < 0.001 | |
Aerobic bacteria (with GBS) | 7.31 (4.14–12.91) | < 0.001 | 6.85 (4.61–10.18) | < 0.001 |
DF | 11 | 5 | ||
AICc | 287.7 | 275.0 | ||
ΔAICc | 12.7 | 0.0 |
Ciliated Peritrichous Protozoa in a Tezontle-Packed Sequencing Batch Reactor as Potential Indicators of Water Quality Molecular Characterization of Aspergillus flavus Strains Isolated from Animal FeedsProduction and Quantification of Virulence Factors in Malassezia SpeciesScreening of Toxin Genes in Methicillin-Resistant Staphylococcus aureus Clinical Isolates from a Hospital Setting in a Tertiary Hospital in Northern CyprusOmicron SARS-CoV-2 Variants in an In Silico Genomic Comparison Study with the Original Wuhan Strain and WHO-Recognized Variants of ConcernIsolation, Identification, and Fermentation Medium Optimization of a Caproic Acid‑Producing Enterococcus casseliflavus Strain from Pit Mud of Chinese Strong Flavor Baijiu EcosystemIn Vivo Efficacy ofBacillus velezensis Isolated from Korean Gochang Bokbunja Vinegar against Carbapenem-ResistantKlebsiella pneumoniae InfectionsRapid and Simple Approaches for Diagnosis of Staphylococcus aureus in Bloodstream InfectionsThe Emergence of Colistin- and Imipenem-Associated Multidrug Resistance in Escherichia coli Isolates from Retail MeatCharacterization of Fecal Microbiomes of Osteoporotic Patients in Korea Retrospective Analysis of the Ureaplasma spp. Prevalence with Reference to Other Genital Tract Infections in Women of Reproductive AgeEvaluation of Cell-Free DNA-Based Next-Generation Sequencing for Identifying Pathogens in Bacteremia Patients