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Background: Predictors of spontaneous preterm birth in primigravid women remain undetermined., Aim: We evaluated whether biomarkers in vaginal secretions and/or differences in the dominant bacterium in the vaginal microbiome predicted the risk for spontaneous preterm birth in primigravid women with a cervical length >25mm., Study Design: In a prospective study, 146 second trimester pregnant women with their first conception and a cervix >25mm were enrolled. The vaginal microbiome composition was characterized by analysis of 16S ribosomal RNA gene sequences. The concentrations of d- and l-lactic acid, matrix metalloproteinase (MMP) 2, 8 and 9 and tissue inhibitor of metalloproteinase (TIMP) 1 and 2 in vaginal secretions were measured by ELISA. Cervical length was determined by vaginal ultrasonography. Pregnancy outcome data were subsequently collected. There was a spontaneous preterm birth (SPTB) in 13 women (8.9%) while in an additional 8 women (5.5%) preterm delivery was medically indicated. Lactobacillus iners was the dominant vaginal bacterium in 61.5% of women with a SPTB but only in 31.2% of those who delivered at term ( p  = .0354). The vaginal concentration of TIMP-1 ( p  = .0419) and L-lactic acid ( p  = .0495) was higher in women with a SPTB as compared to those who delivered at term. Lactobacillus iners dominance was associated with elevated levels of TIMP-1 ( p  = .0434) and TIMP-2 ( p  = .0161) and lower levels of D-lactic acid ( p  < .0001) compared to when L. crispatus was dominant., Conclusion: In this exploratory study of primigravid women, elevations in vaginal TIMP-1 and L- lactic acid and L. iners dominance in the vaginal microbiome are associated with an increased occurrence of SPTB.

Objectives: Short cervical length is a predictor of preterm birth. We evaluated if there were racial differences in variables associated with cervical length in pregnant Brazilian women., Methods: Cervical length was determined by vaginal ultrasound in 414 women at 21 weeks gestation. All women were seen at the same clinic and analyzed by the same investigators. Women found to have a short cervix (≤25 mm) received vaginal progesterone throughout gestation. Composition of the vaginal microbiome was determined by analysis of the V1-V3 region of the gene coding for bacterial 16S ribosomal RNA. Demographic, clinical and outcome variables were determined by chart review. Subjects were 53.4% White, 37.2% mixed race and 9.4% Black., Results: Pregnancy, medical history and education level were similar in all groups. Mean cervical length was shorter in Black women (28.4 mm) than in White (32.4 mm) or mixed race (32.8 mm) women (p≤0.016) as was the percentage of women with a short cervix (23.1, 12.2, 7.8% in Black, White, mixed race respectively) (p≤0.026). Mean cervical length increased with maternal age in White (p=0.001) and mixed race (p=0.045) women but not Black women. There were no differences in bacterial dominance in the vaginal microbiota between groups. Most women with a short cervix delivered at term., Conclusions: We conclude that Black women in Brazil have a shorter cervical length than White or mixed race women independent of maternal age, pregnancy and demographic history or composition of the vaginal microbiome., (© 2020 Walter de Gruyter GmbH, Berlin/Boston.)

In many impoverished regions of the world, it may not be possible to assess two major risk factors for preterm birth: a short cervical length and the depletion of vaginal lactobacilli. We determined whether measuring specific compounds in vaginal fluid might be a simple, noninvasive, and cost-effective way to predict the bacteria that dominate the vaginal microbiome and indicate the presence of a shortened cervix (<25 mm). Vaginal fluid samples were prospectively collected from mid-trimester pregnant women, and the concentrations of d- and l-lactic acid, tissue inhibitor of matrix metalloproteinases TIMP-1 and TIMP-2, matrix metalloproteinases MMP-2 and MMP-8, the 70-kDa heat shock protein, a2 isoform of vacuolar ATPase, and sequestrome-1 were quantified by an enzyme-linked immunosorbent assay (ELISA). The compositions of vaginal microbiomes were assessed by analysis of the V1-V3 regions of 16S rRNA genes, while cervical length was determined by transvaginal ultrasonography. The vaginal microbiomes could be clustered into five community state types (CSTs), four of which were dominated by a single Lactobacillus species. The dominance of Lactobacillus crispatus or Lactobacillus jensenii in the vaginal microbiome predicted the level of d-lactic acid present. Several of the biomarkers, especially TIMP-1, in combination with the subject's age and race, were significantly associated with cervical length. Using piecewise structural equation modeling, we established a causal network that links CST to cervical length via biomarkers. We concluded that measuring levels of TIMP-1 and d-lactic acid in vaginal secretions might be a straightforward way to assess the risk for preterm birth due to a short cervix and microbiome composition. IMPORTANCE Premature birth and its complications are the largest contributors to infant death in the United States and globally. A short cervical length and the depletion of Lactobacillus species are known risk factors for preterm birth. However, in many resource-poor areas of the world, the technology to test for their occurrence is unavailable, and pregnant women with these risk factors are neither identified nor treated. In this study, we used path analysis to gain an unprecedented understanding of interactions between vaginal microbiome composition, the concentrations of various compounds in vaginal secretions, and cervical length. We identified low-cost point-of-care measures that might be used to identify pregnant women at risk for preterm birth. The use of these measures coupled with appropriate preventative or treatment strategies could reduce the incidence of preterm births in poor areas of the world that lack access to more sophisticated diagnostic methods., (Copyright © 2019 Witkin et al.)

Objective: To evaluate the vaginal and cervical microbiota in women with spinal cord injury compared with mobile women., Methods: Fifty-two women with spinal cord injury (study group) and 57 mobile women (control group) were evaluated in a case-control study. All answered a structured questionnaire and were submitted to the following microbiological tests: microscopic examination of vaginal secretions for Trichomonas vaginalis and yeasts, Nugent score by Gram stain, bacterial culture, yeast culture, and endocervical sampling for Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma species., Results: Candida species detected by direct microscopic examination of vaginal fluid was more common in women with spinal cord injuries than in control women: 17.3% (9/52) compared with 3.5% (2/57), respectively (P=.017). However, the frequency of yeast-positive cultures was similar in both groups (21.2% [10/52] compared with 15.8% [14/57]). Women with spinal cord injury were more likely to have positive vaginal cultures for Escherichia coli (15.4% [8/52] compared with 0% [0/57], P=.002) and Corynebacterium species (25.0% [13/52] compared with 8.8% [5/57], P=.037) and less likely for Lactobacillus species (63.5% [33/52] compared with 94.7% [54/57], P<.001). Women with spinal cord injury were more likely to have intermediate flora by Gram stain (Nugent score 4-6) than did the women in the control group (13.5% [7/52] compared with 1.8% [1/57], P=.033). The frequency of Mycoplasma species detection was similar in both groups (36.9% [18/52] compared with 34.6% [21/57]). No woman in either group was positive for T vaginalis, C trachomatis, or N gonorrhoeae., Conclusion: Women with spinal cord injury have an alteration in their vaginal microbiota away from a Lactobacillus species-dominated flora and a higher concentration of vaginal Candida species than do mobile women.

Cervicitis associated with Chlamydia trachomatis is frequent worldwide, but the factors determining susceptibility to infection remain incompletely determined. We evaluated whether a functional single nucleotide polymorphism at position +874 in the gene coding for interferon gamma (rs2430561) influenced the likelihood of having a cervical C. trachomatis infection. This was a cross-sectional study of 142 sexually-active women attending a general gynaecology service on the outskirts of the city of Fortaleza in northeastern Brazil between August 2011 and August 2012. Endocervical swabs were evaluated for C. trachomatis DNA using hybrid capture. DNA from buccal swabs was utilised for detection of the interferon gamma 874 T/A single nucleotide polymorphism by gene amplification, endonuclease digestion and gel electrophoresis. Nineteen women (13.4%) were positive for C. trachomatis in their cervix. Positivity was 21.7% in women with the A,A genotype versus 7.0% in women with one or two T alleles (p = 0.0227). The variant T allele frequency, associated with elevated interferon gamma production, was 36.2% in women who were negative for C. trachomatis as opposed to 18.4% in women who were positive for a cervical infection with this organism (p = 0.0415). Possession of the T allele at position +874 in the gene coding for interferon gamma is associated with a reduced likelihood of a C. trachomatis cervical infection., (© The Author(s) 2015.)

A lactobacillus-dominant vaginal microbiota has been shown to decrease heterosexual HIV transmission. Nunn et al. now report that a vaginal microbiota dominated by Lactobacillus crispatus is associated with a relative inability of HIV pseudoviral particles to transverse cervicovaginal mucus (CVM) in vitro [mBio 6(5):e01084-15, 2015, doi:10.1128/mBio.01084-15]. The purported inhibitory mechanism is the interaction between carboxyl groups present on HIV and in CVM that occurred only under acidic conditions when carboxyl groups were protonated. L. crispatus produces high levels of lactic acid and results in the lowest vaginal pH when it is the dominant vaginal bacterium. In addition, high levels of lactic acid inhibit the proliferation of other bacteria that might negatively affect CVM structure. The utility of enhancing L. crispatus dominance to inhibit HIV transmission awaits assessment of the influence of ejaculated semen on this property and investigations on the role of Lactobacillus products such as d-lactic acid in this property., (Copyright © 2015 Witkin and Linhares.)

Ureaplasma urealyticum colonization was examined in paired cervical and introital specimens from 56 untreated HIV-seropositive women. Specimens were tested for U. urealyticum by polymerase chain reaction (PCR). Peripheral blood was examined for CD4 lymphocyte counts and HIV RNA concentration. U. urealyticum was detected in the cervix of 38 (69.1%) women. Introital U. urealyticum was present in 16 (28.6%) women, all of whom were cervical-positive. Cervical motion pain was present in 40.0% of women with U. urealyticum in the introitus and cervix, 23.8% of those with only cervical U. urealyticum and 5.9% of women negative for this organism (P=0.03). There was no relation between U. urealyticum colonization and CD4 lymphocyte count. However, 64.3% of women with introital U. urealyticum had circulating HIV RNA levels > 10,000 copies per ml as compared with 28.6% of women with only cervical U. urealyticum and 7.1% of women negative for this organism (P < 0.01).