Chorioamnionitis and bacterial vaginosis

The Role of Prevotella Species in Female Genital Tract Infections

Female genital tract infections (FGTIs) include vaginal infections (e.g., bacterial vaginosis [BV]), endometritis, pelvic inflammatory disease [PID], and chorioamnionitis [amniotic fluid infection]. They commonly occur in women of reproductive age and are strongly associated with multiple adverse health outcomes including increased risk of HIV/sexually transmitted infection acquisition and transmission, infertility, and adverse birth outcomes such as preterm birth. These FGTIs are characterized by a disruption of the cervicovaginal microbiota which largely affects host immunity through the loss of protective, lactic acid-producing Lactobacillus spp. and the overgrowth of facultative and strict anaerobic bacteria. Prevotella species (spp.), anaerobic Gram-negative rods, are implicated in the pathogenesis of multiple bacterial FGTIs. Specifically, P. bivia, P. amnii, and P. timonensis have unique virulence factors in this setting, including resistance to antibiotics commonly used in treatment. Additionally, evidence suggests that the presence of Prevotella spp. in untreated BV cases can lead to infections of the upper female genital tract by ascension into the uterus. This narrative review aims to explore the most common Prevotella spp. in FGTIs, highlight their important role in the pathogenesis of FGTIs, and propose future research in this area.

Animal Models of Chorioamnionitis: Considerations for Translational Medicine

Preterm birth is defined as any birth occurring before 37 completed weeks of gestation by the World Health Organization. Preterm birth is responsible for perinatal mortality and long-term neurological morbidity. Acute chorioamnionitis is observed in 70% of premature labor and is associated with a heavy burden of multiorgan morbidities in the offspring. Unfortunately, chorioamnionitis is still missing effective biomarkers and early placento- as well as feto-protective and curative treatments. This review summarizes recent advances in the understanding of the underlying mechanisms of chorioamnionitis and subsequent impacts on the pregnancy outcome, both during and beyond gestation. This review also describes relevant and current animal models of chorioamnionitis used to decipher associated mechanisms and develop much needed therapies. Improved knowledge of the pathophysiological mechanisms underpinning chorioamnionitis based on preclinical models is a mandatory step to identify early in utero diagnostic biomarkers and design novel anti-inflammatory interventions to improve both maternal and fetal outcomes.

An Insight into Vaginal Microbiome Techniques

There is a unique microbial community in the female lower genital tract known as the vaginal microbiota, which varies in composition and density and provides significant benefits during pregnancy, reproductive cyclicity, healthy newborn delivery, protection from preterm birth, infections such as UTIs, bacterial vaginosis, and so on, and improves the efficacy of treatments for vaginal cancers. Methods: It is necessary to know how the vaginal microbiome is composed in order to make an accurate diagnosis of the diseases listed above. A microbiome’s members are difficult to classify, and the way microbial communities function and influence host–pathogen interactions are difficult to understand. More and more metagenomic studies are able to unravel such complexities due to advances in high-throughput sequencing and bioinformatics. When it comes to vaginal microbiota research, we’ll be looking at the use of modern techniques and strategies that can be used to investigate variations in vaginal microbiota in order to detect diseases earlier, better treat vaginal disorders, and boost women’s health. Discussion: The discussed techniques and strategies may improve the treatment of vaginal disorders and may be beneficial for women’s overall health.

Four major patterns of placental injury: a stepwise guide for understanding and implementing the 2016 Amsterdam consensus

The Amsterdam classification system defines four major patterns of placental injury, maternal vascular malperfusion, fetal vascular malperfusion, acute chorioamnionitis, and villitis of unknown etiology, and lists the histologic findings that characterize each. However, there continues to be uncertainty regarding specific definitions, histologic mimics, grading and staging, and what combination of findings is required to diagnose each pattern of injury in a reproducible fashion. The purpose of this review is to clarify some of these issues by suggesting a stepwise approach to more fully realize the potential of this new classification system. In our view, the critical steps for correctly identifying and communicating each pattern of injury are (1) familiarity with the underlying pathophysiology and known clinical associations, (2) incorporation of important gross findings, (3) learning to recognize underlying architectural alterations and defining features at low power, (4) using higher magnification to narrow the differential diagnosis and assess severity (grading) and duration (staging), and (5) adopting a template for generating standardized placental reports that succinctly provide useful information for patient care and research applications.

In silico trio-biomarkers for bacterial vaginosis revealed by species dominance network analysis

BV (bacterial vaginosis) influences 20%–40% of women but its etiology is still poorly understood. An open question about the BV is which of the hundreds of bacteria found in the human vaginal microbiome (HVM) are the major force driving the vaginal microbiota dysbiosis. Here, we recast the question of microbial causality of BV by asking if there are any prevalent ‘signatures’ (network motifs) in the vaginal microbiome networks associated with it? We apply a new framework [species dominance network analysis by Ma & Ellison (2019): Ecological Monographs) to detect critical structures in HVM networks associated with BV risks and etiology. We reanalyzed the 16 s-rRNA gene sequencing datasets of a mixed-cohort of 25 BV patients and healthy women. In these datasets, we detected 15 trio-motifs that occurred exclusively in BV patients. We failed to find any of these 15 trio-motifs in three additional cohorts of 1535 healthy women. Most member-species of the 15 trio motifs are BV-associated anaerobic bacteria (BVAB), Ravel’s community-state type indicators, or the most dominant species; virtually all species interactions in these trios are high-salience skeletons, suggesting that those trios are strongly connected ‘cults’ associated with the occurrence of BV. The presence of the trio motifs unique to BV may act as indicators for its personalized diagnosis and could help elucidate a more mechanistic interpretation of its risks and etiology. We caution that scarcity of large longitudinal datasets of HVM also limited further verifications of our findings, and these findings require further clinical tests to launch their applications.

The Association Between Vaginal Microbiota Dysbiosis, Bacterial Vaginosis, and Aerobic Vaginitis, and Adverse Pregnancy Outcomes of Women Living in Sub-Saharan Africa: A Systematic Review

Background: Previous studies have described the association between dysbiosis of the vaginal microbiota (VMB) and related dysbiotic conditions, such as bacterial vaginosis (BV) and aerobic vaginitis (AV), and various adverse pregnancy outcomes. There is limited overview of this association from countries in sub-Saharan Africa (SSA), which bear a disproportionally high burden of both vaginal dysbiotic conditions and adverse pregnancy outcomes. This systematic review assesses the evidence on the association between VMB dysbiosis, BV, and AV, and late adverse pregnancy outcomes in women living in SSA.

Methods: The Preferred Reporting Items for Systematic Review and Meta-Analysis Statement (PRISMA) guidelines were followed. Three databases [PubMed, Embase (Ovid), and Cochrane] were used to retrieve observational and intervention studies conducted in SSA that associated VMB dysbiosis, BV, or AV and preterm birth/labor/delivery, preterm rupture of membranes (PROM), low birthweight, small for gestational age, intrauterine growth restriction, intrauterine infection, intrauterine (fetal) death, stillbirth, perinatal death, or perinatal mortality.

Results: Twelve studies out of 693 search records from five SSA countries were included. One study identified a positive association between VMB dysbiosis and low birthweight. Despite considerable differences in study design and outcome reporting, studies reported an association between BV and preterm birth (7/9), low birthweight (2/6), PROM (2/4), intrauterine infections (1/1), and small for gestational age (1/1). None of the retrieved studies found an association between BV and pregnancy loss (5/5) or intrauterine growth retardation (1/1). At least two studies support the association between BV and PROM, low birthweight, and preterm birth in Nigerian pregnant women. No reports were identified investigating the association between AV and late adverse pregnancy outcomes in SSA.

Conclusion: Two of the included studies from SSA support the association between BV and PROM. The remaining studies show discrepancies in supporting an association between BV and preterm birth or low birthweight. None of the studies found an association between BV and pregnancy loss. As for the role of VMB dysbiosis, BV, and AV during pregnancy among SSA women, additional research is needed. These results provide useful evidence for prevention efforts to decrease vaginal dysbiosis and its contribution to adverse pregnancy outcomes in SSA.

Management of clinical chorioamnionitis: an evidence-based approach

This review aimed to examine the existing evidence about interventions proposed for the treatment of clinical chorioamnionitis, with the goal of developing an evidence-based contemporary approach for the management of this condition. Most trials that assessed the use of antibiotics in clinical chorioamnionitis included patients with a gestational age of ≥34 weeks and in labor. The first-line antimicrobial regimen for the treatment of clinical chorioamnionitis is ampicillin combined with gentamicin, which should be initiated during the intrapartum period. In the event of a cesarean delivery, patients should receive clindamycin at the time of umbilical cord clamping. The administration of additional antibiotic therapy does not appear to be necessary after vaginal or cesarean delivery. However, if postdelivery antibiotics are prescribed, there is support for the administration of an additional dose. Patients can receive antipyretic agents, mainly acetaminophen, even though there is no clear evidence of their benefits. Current evidence suggests that the administration of antenatal corticosteroids for fetal lung maturation and of magnesium sulfate for fetal neuroprotection to patients with clinical chorioamnionitis between 24 0/7 and 33 6/7 weeks of gestation, and possibly between 23 0/7 and 23 6/7 weeks of gestation, has an overall beneficial effect on the infant. However, delivery should not be delayed to complete the full course of corticosteroids and magnesium sulfate. Once the diagnosis of clinical chorioamnionitis has been established, delivery should be considered, regardless of the gestational age. Vaginal delivery is the safer option and cesarean delivery should be reserved for standard obstetrical indications. The time interval between the diagnosis of clinical chorioamnionitis and delivery is not related to most adverse maternal and neonatal outcomes. Patients may require a higher dose of oxytocin to achieve adequate uterine activity or greater uterine activity to effect a given change in cervical dilation. The benefit of using continuous electronic fetal heart rate monitoring in these patients is unclear. We identified the following promising interventions for the management of clinical chorioamnionitis: (1) an antibiotic regimen including ceftriaxone, clarithromycin, and metronidazole that provides coverage against the most commonly identified microorganisms in patients with clinical chorioamnionitis; (2) vaginal cleansing with antiseptic solutions before cesarean delivery with the aim of decreasing the risk of endometritis and, possibly, postoperative wound infection; and (3) antenatal administration of N-acetylcysteine, an antioxidant and antiinflammatory agent, to reduce neonatal morbidity and mortality. Well-powered randomized controlled trials are needed to assess these interventions in patients with clinical chorioamnionitis.

Gardnerella vaginalis as a Cause of Bacterial Vaginosis: Appraisal of the Evidence From in vivo Models

Koch's postulates dictate the use of experimental models to illustrate features of human disease and provide evidence for a singular organism as the cause. The underlying cause(s) of bacterial vaginosis (BV) has been debated in the literature for over half a century. In 1955, it was first reported that a bacterium now known as Gardnerella vaginalis may be the cause of a condition (BV) resulting in higher vaginal pH, thin discharge, a fishy odor, and the presence of epithelial cells covered in bacteria. Here we review contemporary and historical studies on BV with a focus on reports of experimental infections in human or animal models using Gardnerella vaginalis. We evaluate experimental evidence for the hypothesis that G. vaginalis is sufficient to trigger clinical features of BV or relevant health complications associated with the condition. Additionally, we evaluate in vivo models of co-infection employing G. vaginalis together with other bacterial species to investigate evidence for the hypothesis that G. vaginalis may encourage colonization or virulence of other potential pathogens. Together, these studies paint a complex picture in which G. vaginalis has both direct and indirect roles in the features, health complications, and co-infections associated with BV. We briefly review the current taxonomic landscape and genetic diversity pertinent to Gardnerella and note the limitations of sequence-based studies using different marker genes and priming sites. Although much more study is needed to refine our understanding of how BV develops and persists within the human host, applications of the experimental aspects of Koch's postulates have provided an important glimpse into some of the causal relationships that may govern this condition in vivo.

Immunological Role of the Maternal Uterine Microbiome in Pregnancy: Pregnancies Pathologies and Alterated Microbiota

Understanding what happens at the time of embryo implantation has been the subject of significant research. Investigators from many differing fields including maternal fetal medicine, microbiology, genetics, reproductive endocrinology and immunology have all been studying the moment the embryo interacts with the maternal endometrium. A perfect relationship between the uterus and the embryo, mediated by a tightly controlled interaction between the embryo and the endometrium, is required for successful implantation. Any factors affecting this communication, such as altered microbiome may lead to poor reproductive outcomes. Current theories suggest that altered microbiota may trigger an inflammatory response in the endometrium that affects the success of embryo implantation, as inflammatory mediators are tightly regulated during the adhesion of the blastocyst to the epithelial endometrial wall. In this review, we will highlight the various microbiome found during the periconceptual period, the microbiomes interaction with immunological responses surrounding the time of implantation, its effect on implantation, placentation and ultimately maternal and neonatal outcomes.

Cervicovaginal microbiota, women's health, and reproductive outcomes

The human microbiome project has shown a remarkable diversity of microbial ecology within the human body. The vaginal microbiota is unique in that in many women it is most often dominated by Lactobacillus species. However, in some women it lacks Lactobacillus spp. and is comprised of a wide array of strict and facultative anaerobes, a state that broadly correlates with increased risk for infection, disease, and poor reproductive and obstetric outcomes. Interestingly, the level of protection against infection can also vary by species and strains of Lactobacillus, and some species although dominant are not always optimal. This factors into the risk of contracting sexually transmitted infections and possibly influences the occurrence of resultant adverse reproductive outcomes such as tubal factor infertility. The composition and function of the vaginal microbiota appear to play an important role in pregnancy and fertility treatment outcomes and future research in this field will shed further translational mechanistic understanding onto the interplay of the vaginal microbiota with women's health and reproduction.

Vaginal dysbiosis increases risk of preterm fetal membrane rupture, neonatal sepsis and is exacerbated by erythromycin

BACKGROUND

Preterm prelabour rupture of the fetal membranes (PPROM) precedes 30% of preterm births and is a risk factor for early onset neonatal sepsis. As PPROM is strongly associated with ascending vaginal infection, prophylactic antibiotics are widely used. The evolution of vaginal microbiota compositions associated with PPROM and the impact of antibiotics on bacterial compositions are unknown.

METHODS

We prospectively assessed vaginal microbiota prior to and following PPROM using MiSeq-based sequencing of 16S rRNA gene amplicons and examined the impact of erythromycin prophylaxis on bacterial load and community structures.

RESULTS

In contrast to pregnancies delivering at term, vaginal dysbiosis characterised by Lactobacillus spp. depletion was present prior to the rupture of fetal membranes in approximately a third of cases (0% vs. 27%, P = 0.026) and persisted following membrane rupture (31%, P = 0.005). Vaginal dysbiosis was exacerbated by erythromycin treatment (47%, P = 0.00009) particularly in women initially colonised by Lactobacillus spp. Lactobacillus depletion and increased relative abundance of Sneathia spp. were associated with subsequent funisitis and early onset neonatal sepsis.

CONCLUSIONS

Our data show that vaginal microbiota composition is a risk factor for subsequent PPROM and is associated with adverse short-term maternal and neonatal outcomes. This highlights vaginal microbiota as a potentially modifiable antenatal risk factor for PPROM and suggests that routine use of erythromycin for PPROM be re-examined.

The vaginal microbiome of pregnant women is less rich and diverse, with lower prevalence of Mollicutes, compared to non-pregnant women

The vaginal microbiome plays an important role in maternal and neonatal health. Imbalances in this microbiota (dysbiosis) during pregnancy are associated with negative reproductive outcomes, such as pregnancy loss and preterm birth, but the underlying mechanisms remain poorly understood. Consequently a comprehensive understanding of the baseline microbiome in healthy pregnancy is needed. We characterized the vaginal microbiomes of healthy pregnant women at 11–16 weeks of gestational age (n = 182) and compared them to those of non-pregnant women (n = 310). Profiles were created by pyrosequencing of the cpn60 universal target region. Microbiome profiles of pregnant women clustered into six Community State Types: I, II, III, IVC, IVD and V. Overall microbiome profiles could not be distinguished based on pregnancy status. However, the vaginal microbiomes of women with healthy ongoing pregnancies had lower richness and diversity, lower prevalence of Mycoplasma and Ureaplasma and higher bacterial load when compared to non-pregnant women. Lactobacillus abundance was also greater in the microbiomes of pregnant women with Lactobacillus-dominated CSTs in comparison with non-pregnant women. This study provides further information regarding characteristics of the vaginal microbiome of low-risk pregnant women, providing a baseline for forthcoming studies investigating the diagnostic potential of the microbiome for prediction of adverse pregnancy outcomes.

The Association between Prenatal Yoga and the Administration of Ritodrine Hydrochloride during Pregnancy: An Adjunct Study of the Japan Environment and Children's Study

Introduction

While the beneficial effects of prenatal yoga have been reported in recent years, little is known about its effectiveness in pregnant Japanese women. Despite several adverse effects, ritodrine hydrochloride is frequently prescribed to suppress preterm labor in Japan, and its usage may therefore indicate cases of preterm labor. This study aimed to clarify the association between prenatal yoga and ritodrine hydrochloride use during pregnancy.

Methods

An observational study was conducted as an adjunct study by the Hokkaido unit of the Japan Environment and Children’s Study. Information on prenatal yoga practice was collected using a self-questionnaire between March 21, 2012, and July 7, 2015, targeting women who had recently delivered. Ritodrine hydrochloride use was identified from medical records. A total of 2,692 women were analyzed using logistic regression models that adjusted for possible confounders.

Results

There were 567 (21.1%) women who practiced prenatal yoga, which was associated with a lower risk of ritodrine hydrochloride use (adjusted odds ratio [OR] 0.77; 95% CI 0.61–0.98). This was especially evident in women with a total practice duration that exceeded 900 minutes throughout their pregnancy (adjusted OR 0.54; 95% CI 0.38–0.76). A sensitivity analysis that excluded patients with threatened abortion during the study period produced similar results.

Conclusions

Prenatal yoga was associated with a lower risk of ritodrine hydrochloride use, particularly in women with more than 900 minutes of practice time over the course of their pregnancy. Prenatal yoga may be a beneficial option for pregnant women in the selection of alternative therapies.

The vaginal microbiome during pregnancy and the postpartum period in a European population

The composition and structure of the pregnancy vaginal microbiome may influence susceptibility to adverse pregnancy outcomes. Studies on the pregnant vaginal microbiome have largely been limited to Northern American populations. Using MiSeq sequencing of 16S rRNA gene amplicons, we characterised the vaginal microbiota of a mixed British cohort of women (n = 42) who experienced uncomplicated term delivery and who were sampled longitudinally throughout pregnancy (8–12, 20–22, 28–30 and 34–36 weeks gestation) and 6 weeks postpartum. We show that vaginal microbiome composition dramatically changes postpartum to become less Lactobacillus spp. dominant with increased alpha-diversity irrespective of the community structure during pregnancy and independent of ethnicity. While the pregnancy vaginal microbiome was characteristically dominated by Lactobacillus spp. and low alpha-diversity, unlike Northern American populations, a significant number of pregnant women this British population had a L. jensenii-dominated microbiome characterised by low alpha-diversity. L. jensenii was predominantly observed in women of Asian and Caucasian ethnicity whereas L. gasseri was absent in samples from Black women. This study reveals new insights into biogeographical and ethnic effects upon the pregnancy and postpartum vaginal microbiome and has important implications for future studies exploring relationships between the vaginal microbiome, host health and pregnancy outcomes.

The relationship between the intensity of intra-amniotic inflammation and the presence and severity of acute histologic chorioamnionitis in preterm gestation

OBJECTIVE

Acute histologic chorioamnionitis (HCA) is associated with an increased risk of perinatal mortality and morbidity. The purpose of this study was to determine the relationship between the intensity of intra-amniotic inflammation (IAI) and the severity of acute HCA in preterm gestation.

METHODS

The relationship between the intensity of IAI and the presence and severity of acute HCA was examined in 412 patients with singleton gestations who delivered within 120 h of transabdominal amniocentesis. The concentration of amniotic fluid (AF) matrix metalloproteinase (MMP)-8 was assayed to determine the presence and intensity of IAI. Acute HCA was defined as the presence of inflammatory change in any tissue samples according to the criteria previously reported. The total grade of acute HCA was used to determine the severity of HCA.

RESULTS

(1) Patients with IAI had a significantly higher rate of acute HCA than those without IAI [76.9% (133/173)] versus 20.9% (50/239), p < 0.001]. The AF MMP-8 concentration was significantly higher in patients with acute HCA than in those without acute HCA (median [range]; 188.3 ng/ml [0.3-6142.6] versus 1.8 ng/ml [0.3-2845.5], p < 0.001); (2) Of 183 patients with acute HCA, the AF MMP-8 concentration was positively correlated with the severity of acute HCA (p < 0.001).

CONCLUSIONS

AF MMP-8 concentration was not only a predictor of the presence of acute HCA, but its concentration also correlated with the severity of acute HCA. The higher the intensity of IAI, the worse the degree of acute HCA in preterm gestation.

The diagnostic performance of the Mass Restricted (MR) score in the identification of microbial invasion of the amniotic cavity or intra-amniotic inflammation is not superior to amniotic fluid interleukin-6

OBJECTIVE

Intra-amniotic infection/inflammation are major causes of spontaneous preterm labor and delivery. However, diagnosis of intra-amniotic infection is challenging because most are subclinical and amniotic fluid (AF) cultures take several days before results are available. Several tests have been proposed for the rapid diagnosis of microbial invasion of the amniotic cavity (MIAC) or intra-amniotic inflammation. The aim of this study was to examine the diagnostic performance of the AF Mass Restricted (MR) score in comparison with interleukin-6 (IL-6) and matrix metalloproteinase-8 (MMP-8) for the identification of MIAC or inflammation.

METHODS

AF samples were collected from patients with singleton gestations and symptoms of preterm labor (n = 100). Intra-amniotic inflammation was defined as >100 white blood cells/mm(3) (WBCs) in AF; MIAC was defined as a positive AF culture. AF IL-6 and MMP-8 were determined using ELISA. The MR score was obtained using the Surface-Enhanced Laser Desorption Ionization Time of Flight (SELDI-TOF) mass spectrometry. Sensitivity and specificity were calculated and logistic regression models were fit to construct receiver-operating characteristic (ROC) curves for the identification of each outcome. The McNemar's test and paired sample non-parametric statistical techniques were used to test for differences in diagnostic performance metrics.

RESULTS

(1) The prevalence of MIAC and intra-amniotic inflammation was 34% (34/100) and 40% (40/100), respectively; (2) there were no significant differences in sensitivity of the three tests under study (MR score, IL-6 or MMP-8) in the identification of either MIAC or intra-amniotic inflammation (using the following cutoffs: MR score >2, IL-6 >11.4 ng/mL, and MMP-8 >23 ng/mL); (3) there was no significant difference in the sensitivity among the three tests for the same outcomes when the false positive rate was fixed at 15%; (4) the specificity for IL-6 was not significantly different from that of the MR score in identifying either MIAC or intra-amniotic inflammation when using previously reported thresholds; and (5) there were no significant differences in the area under the ROC curve when comparing the MR score, IL-6 or MMP-8 in the identification of these outcomes.

CONCLUSIONS

IL-6 and the MR score have equivalent diagnostic performance in the identification of MIAC or intra-amniotic inflammation. Selection from among these three tests (MR score, IL-6 and MMP-8) for diagnostic purposes should be based on factors such as availability, reproducibility, and cost. The MR score requires a protein chip and a SELDI-TOF instrument which are not widely available or considered "state of the art". In contrast, immunoassays for IL-6 can be performed in the majority of clinical laboratories.

The composition and stability of the vaginal microbiota of normal pregnant women is different from that of non-pregnant women

BACKGROUND

This study was undertaken to characterize the vaginal microbiota throughout normal human pregnancy using sequence-based techniques. We compared the vaginal microbial composition of non-pregnant patients with a group of pregnant women who delivered at term.

RESULTS

A retrospective case-control longitudinal study was designed and included non-pregnant women (n = 32) and pregnant women who delivered at term (38 to 42 weeks) without complications (n = 22). Serial samples of vaginal fluid were collected from both non-pregnant and pregnant patients. A 16S rRNA gene sequence-based survey was conducted using pyrosequencing to characterize the structure and stability of the vaginal microbiota. Linear mixed effects models and generalized estimating equations were used to identify the phylotypes whose relative abundance was different between the two study groups. The vaginal microbiota of normal pregnant women was different from that of non-pregnant women (higher abundance of Lactobacillus vaginalis, L. crispatus, L. gasseri and L. jensenii and lower abundance of 22 other phylotypes in pregnant women). Bacterial community state type (CST) IV-B or CST IV-A characterized by high relative abundance of species of genus Atopobium as well as the presence of Prevotella, Sneathia, Gardnerella, Ruminococcaceae, Parvimonas, Mobiluncus and other taxa previously shown to be associated with bacterial vaginosis were less frequent in normal pregnancy. The stability of the vaginal microbiota of pregnant women was higher than that of non-pregnant women; however, during normal pregnancy, bacterial communities shift almost exclusively from one CST dominated by Lactobacillus spp. to another CST dominated by Lactobacillus spp.

CONCLUSION

We report the first longitudinal study of the vaginal microbiota in normal pregnancy. Differences in the composition and stability of the microbial community between pregnant and non-pregnant women were observed. Lactobacillus spp. were the predominant members of the microbial community in normal pregnancy. These results can serve as the basis to study the relationship between the vaginal microbiome and adverse pregnancy outcomes.

The vaginal microbiota of pregnant women who subsequently have spontaneous preterm labor and delivery and those with a normal delivery at term

BACKGROUND

This study was undertaken to determine whether the vaginal microbiota of pregnant women who subsequently had a spontaneous preterm delivery is different from that of women who had a term delivery.

RESULTS

This was a nested case-control study of pregnant women who had a term delivery (controls) and those who had a spontaneous preterm delivery before 34 weeks of gestation (cases). Samples of vaginal fluid were collected longitudinally and stored at -70°C until assayed. A microbial survey using pyrosequencing of V1-V3 regions of 16S rRNA genes was performed. We tested the hypothesis of whether the relative abundance of individual microbial species (phylotypes) was different between women who had a term versus preterm delivery. A suite of bioinformatic and statistical tools, including linear mixed effects models and generalized estimating equations, was used. We show that: 1) the composition of the vaginal microbiota during normal pregnancy changed as a function of gestational age, with an increase in the relative abundance of four Lactobacillus spp., and decreased in anaerobe or strict-anaerobe microbial species as pregnancy progressed; 2) no bacterial taxa differed in relative abundance between women who had a spontaneous preterm delivery and those who delivered at term; and 3) no differences in the frequency of the vaginal community state types (CST I, III, IV-B) between women who delivered at term and those who delivered preterm were detected.

CONCLUSIONS

The bacterial taxa composition and abundance of vaginal microbial communities, characterized with 16S rRNA gene sequence-based techniques, were not different in pregnant women who subsequently delivered a preterm neonate versus those who delivered at term.

Increased tissue levels of omega-3 polyunsaturated fatty acids prevents pathological preterm birth

Omega-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) have anti-inflammatory effects. Preterm birth is an important problem in modern obstetrics and one of the main causes is an inflammation. We here showed that abundance of omega-3 fatty acids reduced the incidence of preterm birth induced by LPS with fat-1 mice, capable of converting omega-6 to omega-3 fatty acids. We also indicated that the gene expression of IL-6 and IL-1β in uteruses and the number of cervical infiltrating macrophages were reduced in fat-1 mice. The analyses of lipid metabolomics showed the high level of 18-hydroxyeicosapentaenoate in fat-1 mice, which was derived from EPA and was metabolized to anti-inflammatory product named resolvin E3 (RvE3). We finally showed that the administration of RvE3 to LPS-exposed pregnant wild type mice lowered the incidence of preterm birth. Our data suggest that RvE3 could be a potential new therapeutic for the prevention of preterm birth.

[Is the bacterial vaginosis risk factor of prematurity? Study of a cohort of 1336 patients in the hospital of Arras]

BACKGROUND

Among risk factors of prematurity, bacterial vaginosis (BV) could play an important role, but few studies took place in our country.

AIM

In a French population of women booking in a hospital maternity, to search a link between prematurity and BV in the first trimester of pregnancy.

METHODS

A hospital cohort study was carried out between May 2006 and September 1(st), 2009. Pregnant women were screening for BV before 13+6 weeks' gestation. BV was determined by a Gram-Stained Vaginal score greater or equal to 7.

RESULTS

One thousand three hundred and thirty-six patients were included in the study among whom 203 patients had BV and 1133 patients did not have. The presence of BV was significantly associated with preterm delivery (OR: 1.6; 95% IC: 1.1-2.7). But this increase concerned only the spontaneous prematurity (ORa: 1.8, 95% IC: 1.0-3.2) and the statistical association disappeared after taking into account maternal tobacco addiction and socio-economic weak level (ORa: 1.6; 95% IC: 0.9-2.9). At the patient with BV, moreover, the risk of miscarriage before 16SA was significantly augmented at the patient with BV (OR: 3.4; 95% IC: 1.1-10.4), but this risk disappeared after taking into account tobacco addiction and maternal level of studies (ORa: 1.9; 95% IC: 0.5-7.2).

CONCLUSION

The presence of BV in the first trimester of pregnancy seems to be associated with increased risks of preterm delivery and early spontaneous miscarriage. However, this relation seems to be partly linked to a level of weaker study and a more frequent tobacco addiction among the women with BV.

Aerobic vaginitis in pregnancy

Aerobic vaginitis (AV) is an alteration in vaginal bacterial flora that differs from bacterial vaginosis (BV). AV is characterised by an abnormal vaginal microflora accompanied by an increased localised inflammatory reaction and immune response, as opposed to the suppressed immune response that is characteristic of BV. Given the increased local production of interleukin (IL)-1, IL-6 and IL-8 associated with AV during pregnancy, not surprisingly AV is associated with an increased risk of preterm delivery, chorioamnionitis and funisitis of the fetus. There is no consensus on the optimal treatment for AV in pregnant or non-pregnant women, but a broader spectrum drug such as clindamycin is preferred above metronidazole to prevent infection-related preterm birth. The exact role of AV in pregnancy, the potential benefit of screening, and the use of newer local antibiotics, disinfectants, probiotics and immune modulators need further study.

The vaginal microbiome: new information about genital tract flora using molecular based techniques

Vaginal microbiome studies provide information that may change the way we define vaginal flora. Normal flora appears dominated by one or two species of Lactobacillus. Significant numbers of healthy women lack appreciable numbers of vaginal lactobacilli. Bacterial vaginosis (BV) is not a single entity, but instead consists of different bacterial communities or profiles of greater microbial diversity than is evident from cultivation-dependent studies. BV should be considered a syndrome of variable composition that results in different symptoms, phenotypical outcomes, and responses to different antibiotic regimens. This information may help to elucidate the link between BV and infection-related adverse outcomes of pregnancy.

Placental chorioamnionitis at term: epidemiology and follow-up in childhood

The objective was to identify histologic chorioamnionitis ("amnionitis") in the placental disc at term and to investigate associations with demographic, lifestyle, and pregnancy factors and with allergic diseases, atopy, and intelligence quotients in childhood. The setting was a population-based case control study of small-for-gestational age infants at term. One thousand and twelve placentas were assessed histologically for amniocentric inflammation of fetal and/or maternal origin using conservative criteria. Data were collected at birth by maternal interview and from medical records. Follow-up data were obtained from 439 and 418 children at 3.5 and 7 years of age, respectively. Amnionitis was identified in 145 placentas (14.3%), with maternal reaction in 97.2% and fetal reaction in 48.3%. In multivariable analysis any amnionitis was significantly associated with a time from membrane rupture to delivery of 6 to 12 hours, but not with times beyond 12 hours, a duration of total labor exceeding 12 hours, ethnicity (incidences ranging from 8.8% in Indians to 23.5% in Chinese), male infant gender, and anaesthesia during labor, and amnionitis was negatively associated with induction of labor. No associations were found with later allergic disease, atopy, or intelligence quotients. This high incidence of histologic amnionitis at term is similar to historical estimates, despite large reductions in time-related risk factors during labor. Significant ethnic variations contribute to the high incidence and are unexplained, but variation in genetic polymorphisms for susceptibility factors is a possibility. "Silent" histologic amnionitis is a frequent cause of fetal immune activation with potential effects in later life.

A critical assessment of adverse pregnancy outcome and periodontal disease

BACKGROUND

Pre-term birth is a major cause of infant mortality and morbidity that has considerable societal, medical, and economic costs. The rate of pre-term birth appears to be increasing world-wide and efforts to prevent or reduce its prevalence have been largely unsuccessful.

AIM

To review the literature for studies investigating periodontal disease as a possible risk factor for pre-term birth and adverse pregnancy outcomes.

MAIN FINDINGS AND CONCLUSION

Variability among studies in definitions of periodontal disease and adverse pregnancy outcomes as well as widespread inadequate control for confounding factors and possible effect modification make it difficult to base meaningful conclusions on published data. However, while there are indications of an association between periodontal disease and increased risk of adverse pregnancy outcome in some populations, there is no conclusive evidence that treating periodontal disease improves birth outcome. Based on a critical qualitative review, available evidence from clinical trials indicates that, although non-surgical mechanical periodontal treatment in the second trimester of pregnancy is safe and effective in reducing signs of maternal periodontal disease, it does not reduce the rate of pre-term birth. Clinical trials currently underway will further clarify the potential role of periodontal therapy in preventing adverse birth outcomes. Regardless of the outcomes of these trials, it is recommended that large, prospective cohort studies be conducted to assess risk for adverse pregnancy outcome in populations with periodontal disease. It is critical that periodontal exposure and adverse birth outcomes be clearly defined and the many potential confounding factors and possible effect modifiers for adverse pregnancy outcome be controlled in these studies. If periodontal disease is associated with higher risk of adverse pregnancy outcome in these specific populations, large multicenter randomized-controlled trials will be needed to determine if prevention or treatment of periodontal disease, perhaps combined with other interventions, has an effect on adverse pregnancy outcome in these women.

The role of perinatal pathological examination in subclinical infection in obstetrics

Infectious agents are associated with a wide range of obstetric complications and pathological processes affecting the placenta, membranes and fetus. In some cases there will be associated maternal symptoms and signs indicating an infectious aetiology, but in the majority such infection is subclinical, and specific diagnosis or confirmation is achieved following pathological examination of the delivered placenta and/or fetus. There are two major groups of microorganism-related mechanisms associated with significant perinatal morbidity and mortality. First, ascending genital-tract infection, almost always bacterial, which ranges from localized choriodecidual inflammation to frank chorioamnionitis with fetal sepsis; this is a major cause of mid-trimester miscarriage and severe preterm delivery, and more recent data suggest that it may also have potentially important effects via cytokine release mediating neonatal cerebral injury. Second, haematogenous spread of maternal systemic infection--bacterial, viral or parasitic--which may result in isolated placental effects or transmission to the fetus with associated developmental abnormalities and neonatal complications. In many cases distinctive histopathological findings are described, and in addition a wide range of techniques is now available for culture and microscopy to confirm these diagnoses; such techniques include highly specific immunohistochemical markers and sensitive molecular diagnostic techniques such as the polymerase chain reaction. It is likely that with increasingly widespread availability of these investigative approaches to obstetric pathology, a greater understanding of the role of infectious agents in obstetric complications will become apparent.

Infections and other inflammatory conditions

The etiology of cerebral palsy and other related perinatal brain injuries is poorly understood. Infections of the central nervous system are rare but important causes of neurodisability. Recent evidence suggests that infections and other inflammatory conditions apparently limited to the placenta are also associated with an increased risk of neurologic impairment. A major hypothesis to explain this connection is that cytokines, activated inflammatory cells, and other mediators of the innate immune response are released into the fetal circulation where they can directly or indirectly affect the development or integrity of the central nervous system. This review surveys the organisms, mediators, and placental lesions that have been associated with perinatal brain injury.

First trimester bacterial vaginosis, individual microorganism levels, and risk of second trimester pregnancy loss among urban women

OBJECTIVE

To examine the role of first trimester bacterial vaginosis (BV) and level of BV-associated microorganisms, diagnosed using the Nugent gram stain criteria and the risk of second trimester pregnancy loss among urban women.

DESIGN

Prospective cohort study.

SETTING

Urban prenatal care clinics.

PATIENT(S)

Women presenting for their first prenatal care visit who had completed 12 weeks gestation or less and resided within Philadelphia, Pennsylvania.

MAIN OUTCOME MEASURE(S)

Pregnancy loss.

RESULT(S)

Of 1948 women enrolled at a mean gestational age of 10 weeks (range 7.4 to 12.6 weeks), those with the highest level of BV-related vaginal flora alteration compared with women with normal vaginal flora had over a twofold increased risk of second trimester pregnancy loss after adjustment for confounders (adjusted hazard ratio [aHR] 2.49, 95% confidence interval [CI] 1.13 to 5.48). Low Lactobacillus spp. and the absence of Lactobacillus spp. were also significantly related to the risk of second trimester pregnancy loss (aHR 1.32, 95% CI 1.10-1.64; aHR 2.30, 95% CI 1.09-4.85; respectively).

CONCLUSION(S)

Overall BV positivity was not related to second trimester pregnancy loss. Comparing the highest to lowest tertile of BV positivity in early pregnancy conferred a two-fold increased risk of second trimester pregnancy loss and low amounts or the absence of Lactobacillus spp. in the first trimester also significantly increased the risk of second trimester pregnancy loss.

Inflammatory responses in the placenta and umbilical cord

Histopathological examination of the placenta is the gold standard for evaluating antenatal inflammatory processes that might influence fetal development. Histological chorioamnionitis develops through a well-characterised stereotyped progression of maternal and fetal cellular stages that vary from patient to patient and are amenable to quantification. Increases in the intensity of these responses and their gradual transformation into a chronic phase are important variables that can adversely affect fetal physiology. Under recognised placental inflammatory lesions affecting the decidua, placental villi and fetal vessels are also potentially informative factors that should be taken into account in the studies of adverse pregnancy outcomes. This review summarises the relationships between aetiology, intensity, duration, characteristics and site of histological placental inflammation and suggests how these data may help to better understand the antenatal environment.

Bacterial vaginosis in a cohort of Danish pregnant women: prevalence and relationship with preterm delivery, low birthweight and perinatal infections

OBJECTIVE

To determine the prevalence of bacterial vaginosis (BV) in the second trimester of pregnancy in a Danish population using the Schmidt criteria and to examine whether BV was associated with subsequent preterm delivery, low birthweight or perinatal infections.

DESIGN

Prospective cohort study.

SETTING

Department of Obstetrics and Gynaecology at a University Hospital, Denmark.

POPULATION

Three thousand five hundred and forty pregnant women aged 18 years or more.

METHODS

A smear from the vagina was obtained from all women, air-dried and stored for subsequent diagnosis of BV. After rehydration with isotonic saline, the smear was examined in a phase-contrast microscope at 400x, and the numbers of lactobacilli morphotypes and small bacterial morphotypes were counted. A score for BV was calculated according to the method described by Schmidt. The outcome of pregnancy from 20 weeks of gestation was examined in the 3262 singleton pregnant women who were included in this study before 20 weeks of gestation. The relationship between BV and adverse outcome of pregnancy was examined by univariate and multivariate analyses.

MAIN OUTCOME MEASURES

Prevalence of BV, preterm delivery (<37 weeks), low birthweight (<2500 g), preterm delivery of a low-birthweight infant and clinical chorioamnionitis.

RESULTS

The prevalence of BV was 16%, and the rate of preterm delivery was 5.2% in the study population of 3262 singleton pregnant women who were included before 20 weeks of gestation. Mean birthweight was significantly lower in infants of women with BV than in infants of women without BV (3408 versus 3511 g, P < 0.01). Univariate analyses showed that BV was marginally associated with preterm delivery but significantly associated with low birthweight, preterm delivery of a low birthweight infant, indicated preterm delivery and clinical chorioamnionitis. Multivariate analyses, which adjusted for previous miscarriage, previous preterm delivery, previous conisation, smoking, gestational diabetes, fetal death and preterm premature rupture of membranes, showed that BV was significantly associated with low birthweight (OR 1.95, 95% CI 1.3-2.9), preterm delivery of a low-birthweight infant (OR 2.5, 95% CI 1.6-3.9), indicated preterm delivery (OR 2.4, 95% CI 1.4-4.1) and clinical chorioamnionitis (OR 2.7, 95% CI 1.4-5.1).

CONCLUSIONS

The prevalence of BV determined using the Schmidt criteria in the early second trimester of pregnancy was similar to that found in similar studies. The presence of BV before 20 weeks of gestation was an independent risk factor for delivery of an infant with low birthweight, preterm delivery of a low-birthweight infant, indicated preterm delivery and clinical chorioamnionitis.

Pathophysiology of preterm birth: emerging concepts of maternal infection

Preterm birth remains a significant health concern. Maternal reproductive infections such as bacterial vaginosis pose increased risk for preterm birth, although treatment of bacterial vaginosis has not proven to be universally effective in preterm birth prevention. Maternal oral infection such as clinical periodontal disease has also been identified as a risk factor for preterm birth, and pilot data suggest that oral treatment interventions undertaken during pregnancy may reduce preterm birth risk.

Variation in microbiologic profiles among pregnant women with bacterial vaginosis

OBJECTIVE

The purpose of this study was to determine if clinical findings and sociodemographic variables among bacterial vaginosis (BV)-positive pregnant women are associated with different microbiologic profiles.

STUDY DESIGN

Pregnant women were assessed for BV by Nugent criteria. BV+ women were separated into 6 mutually exclusive microbiologic groups. In unadjusted analyses, we compared (1) sociodemographic and behavioral characteristics, and (2) 3 clinical characteristics among BV+ women with and without Mobiluncus (M+ vs M-). Unadjusted data were analyzed using the chi-square test. Multiple logistic regression was used to assess the likelihood of having clinical signs of BV in women with and without Mobiluncus spp while controlling for confounders.

RESULTS

A total of 1756 BV+ pregnant women were followed. The M+ group (n=702) was significantly more likely than the M- group (n=1054) to be non-Hispanic black (80.9% vs 66.2%; P < .0001), older than 21 years (61.7% vs 48.7%; P < .0001), and to have had more than 3 lifetime sexual partners (66.4% vs 54.9%; P < .0001). The M+ group was also more likely to have clue cells on wet mount (63.9% vs 47.2%; P < .0001) and a positive amine odor after addition of KOH (57.2% vs 45.0%; P=.001). There was no difference in other demographic variables or physician diagnosis of abnormal vaginal discharge. In the adjusted analyses for each clinical outcome, all findings were consistent with the unadjusted analyses.

CONCLUSION

BV+ pregnant women with Mobiluncus spp are more likely to have clue cells present on wet mount, a positive amine odor after KOH preparation, and to be older, non-Hispanic black, and have had more lifetime sexual partners compared to BV+ women without any Mobiluncus species.

[Factors of risk of bacterial vaginosis]

OBJECTIVES

To recognise factors in the host that might condition the appearance of the bacterial vaginosis (BV) syndrome, whether gynae-obstetrical factors, habits of sexual conduct, hygiene, or other factors.

DESIGN

Cross-sectional, observational study.

SETTING

The study was conducted from January 2002 to June 2003 in the Primary Care Dr. Jose Castro Villagrana Community Health Centre at Tlalpan, Mexico City.

PARTICIPANTS

968 patients with an active sexual life who had not taken antibiotics for at least 15 days before the study and who were not menstruating at the moment of taking a swab, 859 of whom had a diagnosis of cervico-vaginitis and 109 had no symptoms.

MAIN MEASUREMENTS

Confidential questionnaire and a cervical-vaginal culture. The Amsel criteria were used to make the diagnosis of bacterial vaginosis.

RESULTS

There was 32.9% prevalence of BV. There was a statistically significant association with factors such as age, start of active sexual life, the number of sexual relations per week, the number of sexual partners, and pregnancy.

CONCLUSIONS

Bacterial vaginosis is the main cause of infectious processes in the vagina. Its appearance appears to be linked to factors involving sexual transmission. Interventions to reduce its prevalence and complications are recommended.

Low-dose secnidazole in the treatment of bacterial vaginosis

OBJECTIVE

To determine whether bacterial vaginosis could be cured with a single 1-g oral dose of secnidazole.

MATERIAL AND METHODS

A total of 80 women were recruited at the outpatient gynecologic clinic of Manuel Noriega Hospital, Maracaibo, Venezuela. Diagnosis and patient enrollment were based on the Amsel criteria. The participants were randomized to 2 groups. In group 1 (n=44) participants received a single 1-g oral dose and in group 2 (n=32) participants received a single 2-g oral dose of secnidazole. Clinical cure was defined as the absence of the characteristic symptoms (a bad odor and a grossly abnormal discharge) and at least 2 of the following: vaginal pH less than 4.5, no fish odor on addition of KOH, and no Gardnerella vaginalis or clue cells on wet-mount examination. Cytologic cure was defined as an absence of G. vaginalis on a Papanicolaou (Pap) smear.

RESULTS

Clinical cure was experienced by 95.5% of the women who received the 1-g oral dose and by 97.4% of the women who received the 2-g oral dose of secnidazole. There was no significant difference between the groups in the clinical resolution of bacterial vaginosis. Following treatment, results were negative for G. vaginalis in 94.7% of the women. In group 1, 41 women (93.2%), and in group 2, 31 women (96.9%) had cytologic cure. The Pap smear revealed G. vaginalis in 3 of the women in group 1 and 1 of the women in group 2 (P=0.47). Twenty-seven women (35.5%) reported mild side effects. More women had adverse effects in group 1 (n=16) than in group 2 (n=11) but this difference was not statistically significant.

CONCLUSION

This clinical study showed that a single 1-g oral dose of secnidazole is effective to cure bacterial vaginosis associated with G. vaginalis.

Can endometrial infection/inflammation explain implantation failure, spontaneous abortion, and preterm birth after in vitro fertilization?

The endometrial cavity is frequently invaded by microorganisms, and subclinical endometrial infection or inflammation may play a role in implantation failure after IVF, spontaneous abortion, and preterm birth. Microbial products and host-inflammatory mediators such as cytokines and chemokines can cause trophoblast apoptosis and the cascade of events leading to expulsion of the embryo or fetus.

The efficacy of vaginal clindamycin for the treatment of abnormal genital tract flora in pregnancy

Objective: To assess the efficacy of 2% clindamycin vaginal cream (CVC) to treat bacterial vaginosis (BV) in pregnancy.

Methods: A prospective, randomized, double-blind, placebo-controlled, tricenter study. Four hundred and four women with BV on Gram stain at their first antenatal clinic visit were randomized to receive a 3-day course of 2% CVC or placebo. The outcome was assessed using an intention to treat analysis at 3 weeks and 6 weeks post-treatment according to three different diagnostic methods based on five criteria (Gram stain and all four elements of clinical composite criteria: vaginal discharge, abnormal vaginal pH, clue cells, amine odor), three criteria (vaginal pH, clue cells, amine odor) or two criteria (clue cells and amine odor) to reflect stringency of diagnosis, historical precedence and government agency recommendations respectively.

Results: Using five diagnostic criteria, 18% of CVC patients were cured and 70.8% either cured and/or improved compared to 1.6% and 12% of placebo patients respectively (p < 0.0001). Using three diagnostic criteria, 44.8% of CVC patients were cured and 77.3% were either cured and/or improved compared to 9.3% and 28.8% of placebo patients respectively (p < 0.0001). Using two diagnostic criteria, 75.0% of CVC patients were cured compared to 18.0% of placebo patients (p < 0.0001). Recurrence rates in those CVC patients successfully treated were approximately 6% at 6 weeks post baseline and 10% at 28 to 34 weeks gestation.

Conclusions: A 3-day course of CVC appears to be well tolerated by the mother and statistically significantly more efficacious than placebo in the treatment of BV during the second trimester of pregnancy.

Possible role of bacterial and viral infections in miscarriages

OBJECTIVE

To determine the role of infections in miscarriages. Chorionic villi from aborted material were subjected to cytogenetic evaluation and analyzed for the presence of Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis, human cytomegalovirus (HCMV), adeno-associated virus (AAV), and human papillomaviruses (HPV).

DESIGN

Retrospective study.

SETTING

University hospital and academic research institution.

MAIN OUTCOME MEASURE(S)

Karyotyping and detection of bacterial and viral DNA by means of polymerase chain reaction (PCR) in placenta specimens.

RESULT(S)

In 54 (50%) of 108 samples the karyotype was normal, in 38 (35%) samples it was abnormal, and in 16 (15%) samples karyotype was undetermined. No U. urealyticum, M. hominis, HCMV, or AAV-2 DNA was detected, while C. trachomatis DNA was detected in one (1%) and HPV DNA in eight (7%) samples. No significant correlation of HPV-positive findings with karyotype status was established.

CONCLUSION(S)

Our findings do not support a role of C. trachomatis, U. urealyticum, M. hominis, HCMV, or AAV infections in miscarriages during the first trimester of pregnancy. However, further investigation should be made to determine a possible involvement of HPVs in the development of genetic abnormalities of the fetus and in miscarriages.

Chorioamnionitis caused by Serratia marcescens in a non-immunocompromised host

A 26 year old pregnant woman with antithrombin III deficiency developed recurrent septicaemia with Serratia marcescens. In spite of the administration of antibiotics, high grade fever persisted. She subsequently manifested lower abdominal pain, and spontaneous abortion occurred. After the abortion, she became completely afebrile. The amnion was turbid, and microscopic examination of the placenta showed haemorrhage and massive infiltration of neutrophils, suggestive of infectious chorioamnionitis. Pulsed field gel electrophoresis showed that isolates from the blood, urine, and vaginal discharge were genetically identical. Intravenous pyelography revealed that she had a bilateral completed double ureter. It was thought that a urinary tract anomaly caused infection with S marcescens, and the pathogen spread to the chorioamnion via the bloodstream. This is the first report of chorioamnionitis caused by S marcescens in a non-immunocompromised host. In addition, these findings indicate that the chorioamnion can serve as a site for persistent infection in normal pregnancies.

Amniotic infection syndrome: nosology and reproducibility of placental reaction patterns

Clinically responsive placental examination seeks to provide useful information regarding the etiology, prognosis, and recurrence risk of pregnancy disorders. The purpose of this study was to assemble and validate a complete set of the placental reaction patterns seen with amniotic fluid infection in the hope that this might provide a standardized diagnostic framework useful for practicing pathologists. Study cases (14 with amniotic fluid infection, 6 controls) were reviewed blindly by six pathologists after agreement on a standard set of diagnostic criteria. After analysis of initial results, criteria were refined and a second, overlapping set of cases were reviewed. Majority vote served as the gold standard. Grading and staging of maternal and fetal inflammatory responses was found to be more reproducible using a two- versus three-tiered grading system than a three- versus five-tiered staging system (overall agreement 81% vs. 71%). Sensitivity, specificity, and efficiency for individual observations ranged from 67-100% (24/30 > 90%). Reproducibility was measured by unweighted kappa values and interpreted as follows: < 0.2, poor; 0.2-0.6, fair/moderate; > 0.6, substantial. Kappa values for the 12 lesions evaluated in 20 cases by the six pathologists were: acute chorioamnionitis/maternal inflammatory response (any, 0.93; severe 0.76; advanced stage, 0.49); chronic (subacute) chorioamnionitis (0.25); acute chorioamnionitis/fetal inflammatory response (any, 0.90; severe, 0.55; advanced stage, 0.52); chorionic vessel thrombi (0.37); peripheral funisitis (0.84); acute villitis (0.90); acute intervillositis/intervillous abscesses (0.65), and decidual plasma cells (0.30). Adoption of this clearly defined, clinically relevant, and pathologically reproducible terminology could enhance clinicopathologic correlation and provide a framework for future clinical research.

BVBlue test for diagnosis of bacterial vaginosis

Bacterial vaginosis (BV) is a disorder of the vaginal ecosystem characterized by a shift in the vaginal flora from the normally predominant Lactobacillus to one dominated by sialidase enzyme-producing mixed flora. It is the most common cause of abnormal vaginal discharge in adult women. The BVBlue system (Gryphus Diagnostics, L.L.C.) is a chromogenic diagnostic test based on the presence of elevated sialidase enzyme in vaginal fluid samples. BVBlue was compared to the standard method for diagnosing BV (Amsel criteria and Nugent score). Fifty-seven nonmenstruating women of > or =16 years of age who presented for a pelvic examination were recruited. Demographic features were collected via a self-administered questionnaire. The Amsel criteria were assessed based on three of four of the following characteristics of vaginal discharge: consistency, odor, pH, and presence of clue cells on Gram stain. BVBlue was compared to the Gram stain and Amsel criteria. The sensitivity, specificity, positive predictive value, and negative predictive value for BVBlue versus the Gram stain and Amsel criteria were 91.7, 97.8, 91.7, and 97.8% and 50.0, 100, 100, and 88.2%, respectively. A significantly greater proportion of patients with a vaginal pH of >4.5, a positive amine test, or with clue cells on vaginal Gram smear were found to have a positive BVBlue test (P < 0.001). Women previously treated for BV were 2.98 times more likely to have another episode of BV. BVBlue is a useful point-of-care diagnostic tool to provide a presumptive diagnosis of BV, especially in situations where microscopic capabilities are unavailable.

Vaginal bacterial flora of pregnant women colonized with group B streptococcus

To elucidate the characteristics of group B streptococcus (GBS)-positive vaginal flora in pregnant women, vaginal cultures were conducted in 4025 women at 22 to 36 weeks of gestation. The results were analyzed by Fisher's exact test. Among 4025 women, 408 were found to be GBS positive and 3617 were GBS negative (GBS-negative group). A total of 1151 bacterial strains were recovered in the GBS-positive group and 6746 strains in the GBS-negative group. The percentages of Gram-positive cocci other than GBS, anaerobes, fungi, and Lactobacillus were 18.8%, 1.4%, 6.0%, and 34.4%, respectively, in the GBS-positive group, and 30.4%, 4.1%, 8.8%, and 53.5% in the GBS-negative group. The percentages were significantly lower in the GBS-positive group ( P < 0.0001, P < 0.0001, P= 0.0012, P < 0.0001, respectively). Judging from the reduction in Lactobacillus, the GBS-positive vaginal flora is not considered a normal flora. However, it is not regarded as a pathogenic flora either, because the isolation rates of anaerobes (strongly associated with bacterial vaginosis) and fungi (occasionally causing vulvovaginal candidiasis) were lower than in the GBS-negative flora. These results suggest that the GBS-positive flora is associated with a lower risk of abnormality during pregnancy and abnormal pregnancy outcome compared with the GBS-negative flora, although this group is one of the most important pathogens in neonatal infections.

Factors linked to bacterial vaginosis in nonpregnant women

OBJECTIVES

The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify other demographic, reproductive, and lifestyle factors associated with bacterial vaginosis.

METHODS

In this cross-sectional study involving 3 clinic sites, 496 nonpregnant women completed a self-administered questionnaire. Their vaginal smears were assessed and cross-validated for bacterial vaginosis.

RESULTS

The prevalence of bacterial vaginosis across clinics ranged from 15% to 30%. In analyses restricted to site 1, adjusted odds ratios (ORs) for bacterial vaginosis remained significant for African American women with 13 or fewer years of education (OR = 5.5, 95% confidence interval [CI] = 2.1, 14.5), hormone use within the past 6 months (OR = 0.5, 95% CI = 0.2, 0.8), and vaginal douching within the past 2 months (OR = 2.9, 95% CI = 1.5, 5.6).

CONCLUSIONS

Two lifestyle factors emerge as strongly associated with bacterial vaginosis: systemic contraceptives appear protective, whereas douching is linked to an increase in prevalence. The temporal relationship between douching and bacterial vaginosis needs further clarification.

Binding of heme by Gardnerella vaginalis

It has been previously demonstrated that Gardnerella vaginalis could acquire iron from a number of different iron-containing compounds, including heme. In this study, the direct binding of heme by G. vaginalis strains was demonstrated utilizing a liquid broth heme-binding assay. Competition studies demonstrated that pretreatment of G. vaginalis cells with other iron sources such as hemoglobin, catalase, and lactoferrin did not affect heme binding. Also, heme binding was not inhibited by preincubation of G. vaginalis cells with protoporphyrin IX. Two potential heme-binding proteins with estimated molecular weights of 30 and 70 kDa were isolated using heme-agarose batch affinity chromatography.

The fetal inflammatory response syndrome and cerebral palsy: yet another challenge and dilemma for the obstetrician

There is increasing evidence demonstrating a relationship between intrauterine infection and the development of neonatal intraventricular haemorrhage and periventricular leukomalacia with the subsequent occurrence of cerebral palsy, which is thought to be mediated through the generation of pro-inflammatory cytokines by the fetus. In the light of this relationship, a review of the current management of intrapartum infection and the associated complications of intrauterine infection such as preterm labour and preterm premature rupture of the membranes would seem timely along with the development of potential strategies which might prevent or ameliorate the effects of the fetal inflammatory response syndrome. The suggested changes in the understanding and management of the fetal inflammatory response syndrome provide a challenge and pose a dilemma for the practising obstetrician.

Choriodecidual inflammatory syndrome (CoDIS) is the leading, and under recognised, cause of early preterm delivery and second trimester miscarriage

Severe preterm birth (delivery before 32 completed weeks of gestation), with or without preterm premature rupture of the membranes (PPROM), remains the leading cause of perinatal mortality. It is proposed that localized inflammation of the chorion and decidua in the membranes immediately above the internal cervical os, with or without amniotic cavity infection and inflammation, is the leading, but under recognised, cause of second trimester miscarriage and severe preterm delivery. The term 'CoDIS' (choriodecidual inflammatory syndrome), may provide a better understanding of the underlying pathophysiology than currently used terminology which over emphasizes the importance of overt intra-amniotic infection as opposed to localized extra-amniotic inflammation which stimulates uterine evacuation.