Vaginal lactobacilli and preterm birth

Vulvovaginal yeast infections during pregnancy and perinatal outcomes: systematic review and meta-analysis

BACKGROUND

Vulvovaginal yeast infections in pregnancy are common and can cause extensive inflammation, which could contribute to adverse pregnancy outcomes. Symptomatic yeast infections are likely to cause more inflammation than asymptomatic. The objective of this study was to investigate associations between symptomatic and asymptomatic vulvovaginal yeast infections in pregnancy and perinatal outcomes.

METHODS

We did a systematic review and searched eight databases until 01 July 2022. We included studies reporting on pregnant women with and without laboratory confirmed vulvovaginal yeast infection and preterm birth or eight other perinatal outcomes. We used random effects meta-analysis to calculate summary odds ratios (OR), 95% confidence intervals (CI) and prediction intervals for the association between yeast infection and outcomes. We described findings from studies with multivariable analyses. We assessed the risk of bias using published tools.

RESULTS

We screened 3909 references and included 57 studies. Only 22/57 studies reported information about participant vulvovaginal symptoms. Preterm birth was an outcome in 35/57 studies (49,161 women). In 32/35 studies with available data, the summary OR from univariable analyses was 1.01 (95% CI 0.84-1.21, I2 60%, prediction interval 0.45-2.23). In analyses stratified by symptom status, we found ORs of 1.44 (95% CI 0.92-2.26) in two studies with ≥ 50% symptomatic participants, 0.84 (95% CI 0.45-1.58) in seven studies with < 50% symptomatic participants, and 1.12 (95% CI 0.94-1.35) in four studies with asymptomatic participants. In three studies with multivariable analysis, adjusted ORs were greater than one but CIs were compatible with there being no association. We did not find associations between vulvovaginal yeast infection and any secondary outcome. Most studies were at high risk of bias in at least one domain and only three studies controlled for confounding.

CONCLUSIONS

We did not find strong statistical evidence of an increased risk for preterm birth or eight other adverse perinatal outcomes, in pregnant women with either symptomatic or asymptomatic vulvovaginal yeast infection. The available evidence is insufficient to make recommendations about testing and treatment of vulvovaginal yeast infection in pregnancy. Future studies should assess vulvovaginal symptoms, yeast organism loads, concomitant vaginal or cervical infections, and microbiota using state-of-the-art diagnostics.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020197564.

A microbiota and dietary metabolite integrates DNA repair and cell death to regulate embryo viability and aneuploidy during aging

During aging, environmental stressors and mutations along with reduced DNA repair cause germ cell aneuploidy and genome instability, which limits fertility and embryo development. Benevolent commensal microbiota and dietary plants secrete indoles, which improve healthspan and reproductive success, suggesting regulation of germ cell quality. We show that indoles prevent aneuploidy and promote DNA repair and embryo viability, which depends on age and genotoxic stress levels and affects embryo quality across generations. In young animals or with low doses of radiation, indoles promote DNA repair and embryo viability; however, in older animals or with high doses of radiation, indoles promote death of the embryo. These studies reveal a previously unknown quality control mechanism by which indole integrates DNA repair and cell death responses to preclude germ cell aneuploidy and ensure transgenerational genome integrity. Such regulation affects healthy aging, reproductive senescence, cancer, and the evolution of genetic diversity in invertebrates and vertebrates.

Adverse pregnancy and birth outcomes associated with Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum: a systematic review and meta-analysis

OBJECTIVES

Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum (genital mycoplasmas) commonly colonise the urogenital tract in pregnant women. This systematic review aims to investigate their role in adverse pregnancy and birth outcomes, alone or in combination with bacterial vaginosis (BV).

METHODS

We searched Embase, Medline and CINAHL databases from January 1971 to February 2021. Eligible studies tested for any of the three genital mycoplasmas during pregnancy and reported on the primary outcome, preterm birth (PTB) and/or secondary outcomes low birth weight (LBW), premature rupture of membranes (PROM), spontaneous abortion (SA) and/or perinatal or neonatal death (PND).Two reviewers independently screened titles and abstracts, read potentially eligible full texts and extracted data. Two reviewers independently assessed risks of bias using published checklists. Random effects meta-analysis was used to estimate summary ORs (with 95% CIs and prediction intervals). Multivariable and stratified analyses were synthesised descriptively.

RESULTS

Of 57/1194 included studies, 39 were from high-income countries. In meta-analysis of unadjusted ORs, M. hominis was associated with PTB (OR 1.87, 95% CI 1.49 to 2.34), PROM, LBW and PND but not SA. U. urealyticum was associated with PTB (OR 1.84, 95% CI 1.34 to 2.55), PROM, LBW, SA and PND. U. parvum was associated with PTB (1.60, 95% CI 1.12 to 2.30), PROM and SA. Nine of 57 studies reported any multivariable analysis. In two studies, analyses stratified by BV status showed that M. hominis and U. parvum were more strongly associated with PTB in the presence than in the absence of BV. The most frequent source of bias was a failure to control for confounding.

CONCLUSIONS

The currently available literature does not allow conclusions about the role of mycoplasmas in adverse pregnancy and birth outcomes, alone or with coexisting BV. Future studies that consider genital mycoplasmas in the context of the vaginal microbiome are needed.

PROSPERO REGISTRATION NUMBER

CRD42016050962.

Genital Mycoplasmas and Biomarkers of Inflammation and Their Association With Spontaneous Preterm Birth and Preterm Prelabor Rupture of Membranes: A Systematic Review and Meta-Analysis

Genital mycoplasmas (GM), such as Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma parvum, and Ureaplasma urealyticum are commonly associated with spontaneous preterm labor (SPTL), spontaneous preterm birth (PTB), and preterm prelabor rupture of membranes (PPROM). This study determined the association between GM and such adverse pregnancy outcomes. We searched for studies published 1980–2019 in MEDLINE, EMBASE, and Web of Science. Studies were eligible when GM was detected during pregnancy. We included 93 and 51 studies in determining the prevalence and the inflammatory biomarkers associated with GM, respectively, using the “metafor” package within R. The protocol was registered with PROSPERO (registration no. CRD42016047297). Women with the studied adverse pregnancy outcomes had significantly higher odds of presence with GM compared to women who delivered at term. For PTB, the odds ratios were: M. hominis (OR: 2.25; CI: 1.35–3.75; I²: 44%), M. genitalium (OR: 2.04; CIL 1.18–3.53; I²: 20%), U. parvum (OR: 1.75; CI: 1.47–2.07; I²: 0%), U. urealyticum (OR: 1.50; CI: 1.08–2.07; I²: 58%). SPTL had significantly higher odds with M. hominis (OR: 1.96; CI: 1.19–3.23; I²: 1%) or U. urealyticum (OR: 2.37; CI: 1.20–4.70; I²: 76%) compared to women without SPTL. Women with PPROM had significantly higher odds with M. hominis (OR: 2.09; CI: 1.42–3.08; I²: 0%) than women without PPROM. However, our subgroup analysis based on the diagnostic test and the sample used for detecting GM showed a higher prevalence of GM in maternal samples than in fetal samples. GM presence of the cervix and vagina was associated with lower odds of PTB and preterm labor (PTL). In contrast, GM presence in the AF, fetal membrane, and placenta was associated with increased odds of PTB and PTL. However, genital mycoplasmas may not elicit the massive inflammation required to trigger PTB. In conclusion, GM presence in the fetal tissues was associated with significantly increased odds of PTB and PTL.

Meta-Analysis of Vaginal Microbiome Data Provides New Insights Into Preterm Birth

Preterm birth (PTB) is defined as the birth of an infant before 37 weeks of gestational age. It is the leading cause of perinatal morbidity and mortality worldwide. In this study, we present a comprehensive meta-analysis of vaginal microbiome in PTB. We integrated raw longitudinal 16S rRNA vaginal microbiome data from five independent studies across 3,201 samples and were able to gain new insights into the vaginal microbiome state in women who deliver preterm in comparison to those who deliver at term. We found that women who deliver prematurely show higher within-sample variance in vaginal microbiome abundance, with the most significant difference observed during the first trimester. Modeling the data longitudinally revealed a number of microbial genera as associated with PTB, including several that were previously known and two newly identified by this meta-analysis: Olsenella and Clostridium sensu stricto. New hypotheses emerging from this integrative analysis can lead to novel diagnostics to identify women who are at higher risk for PTB and potentially inform new therapeutic interventions.

The Unique Microbiome and Innate Immunity During Pregnancy

A successful pregnancy depends on not only the tolerance of the fetal immune system by the mother but also resistance against the threat of hazardous microorganisms. Infection with pathogenic microorganisms during pregnancy may lead to premature delivery, miscarriage, growth restriction, neonatal morbidity, and other adverse outcomes. Moreover, the host also has an intact immune system to avoid these adverse outcomes. It is important to note the presence of normal bacteria in the maternal reproductive tract and the principal role of the maternal-placental-fetal interaction in antimicrobial immunity. Previous studies mainly focused on maternal infection during pregnancy. However, this review summarizes the new views on the study of the maternal microbiome and expounds the innate immune defense mechanism of the maternal vagina and decidua as well as how cytotrophoblasts and syncytiotrophoblasts recognize and kill bacteria in the placenta. Fetal immune systems, thought to be weak, also exhibit an immune defense function that is indispensable for maintaining the safety of the fetus. The skin, lungs, and intestines of the fetus during pregnancy constitute the main immune barriers. These findings will provide a new understanding of the effects of normal microbial flora and how the host resists harmful microbes during pregnancy. We believe that it may also contribute to the reference on the clinical prevention and treatment of gestational infection to avoid adverse pregnancy outcomes.

The Development of the Human Microbiome: Why Moms Matter

The human body is cohabitated with trillions of commensal bacteria that are essential for our health. However, certain bacteria can also cause diseases in the human host. Before the microbiome can be attributed to disease risk and pathogenesis, normal acquisition and development of the microbiome must be understood. Here, we explore the evidence surrounding in utero microbial exposures and the significant of this exposure in the proper development of the fetal and neonatal microbiome. We further explore the development of the fetal and neonatal microbiome and its relationship to preterm birth, feeding practices, and mode of delivery, and maternal diet.

Prevalence of Chlamydia trachomatis in Pregnant Iranian Women: A Systematic Review and Meta-Analysis

Several studies have been conducted regarding the prevalence of Chlamydia trachomatis, Mycoplasma hominis, and Ureaplasma urealyticum in pregnant Iranian women. However, it is necessary to combine the previous results to present a general assessment. We conducted the present study based on systematic review and meta-analysis studies according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched the national and international online databases of MagIran, IranMedex, SID, MedLib, IranDoc, Scopus, PubMed, ISI Web of Knowledge, and Google Scholar search engine for certain MeSH keywords until June 16, 2017. In addition, heterogeneity, sensitivity analysis, subgroup analysis, and publication bias were performed. The data were analyzed using random-effects model and Comprehensive Meta-Analysis version 2 and P value was considered lower than 0.05. The prevalence of Chlamydia trachomatis in 11 surveyed articles that assessed 2864 pregnant Iranian women was 8.74% [95% confidence interval (CI): 5.40-13.84]. The prevalence of Chlamydia trachomatis was estimated 5.73% (95% CI: 2.09-14.73) and 13.55% (95% CI: 11.23-16.25) by enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), respectively which the difference was not significant (P=0.082). The lowest and highest prevalence of Chlamydia trachomatis was estimated in Tehran province [4.96% (95% CI: 2.45-9.810)] and Ardabil province [28.60% (95% CI: 20.61-38.20)], respectively. This difference was statistically significant (P<0.001). Meta-regression for the prevalence of Chlamydia trachomatis based on year of the studies was significant with increasing slope (P=0.017). According to the systematic review, the prevalence of Mycoplasma hominis and Urea plasma urealyticum indicated 2 to 22.8% (from 4 articles) and 9.1 to 19.8% (from 3 articles), respectively. There was no evidence of publication bias (P value for Begg and Eggers' tests was 0.161 and 0.173, respectively). The prevalence of Chlamydia trachomatis is high among pregnant Iranian women. Screening pregnant women as part of preventive measures seem necessary considering the potential for maternal and fetal complications.

The role of Escherichia coli in reproductive health: state of the art

Escherichia coli is a well-known commensal of the normal intestinal microbiome that can also colonize the vaginal microbiome, usually without symptoms. However, E. coli can also be a highly virulent and frequently deadly pathogen. In this review, I will discuss the role E. coli has in reproductive health and disease.

Abnormal vaginal colonization by gram-negative bacteria is significantly higher in pregnancy conceived through infertility treatment compared to natural pregnancy

OBJECTIVE

To compare abnormal vaginal colonization between natural pregnancy and pregnancy by infertility treatment in high-risk parturient women and to examine the association between abnormal vaginal colonization and early-onset neonatal sepsis (EONS).

METHODS

The clinical characteristics, vaginal culture result, and delivery outcome of patients who admitted to our high-risk unit between 2005 and 2014 were retrospectively reviewed and compared. We investigated the prevalence of EONS according to maternal vaginal colonization and examined the concordance between maternal vaginal bacteria and etiologic microorganism causing EONS.

RESULTS

Among 1096 pregnancies, the rate of vaginal colonization by gram-negative bacteria, especially Escherichia coli was significantly higher in pregnancies by infertility treatment after adjustment of confounding variables (E. coli, OR [95% CI]: 2.47 [1.33-4.57], p = 0.004). The rate of EONS was significantly higher in neonates with maternal abnormal vaginal bacteria colonization (OR [95% CI]: 3.38 [1.44-7.93], p = 0.005) after adjusting for confounding variables. Notably, among microorganisms isolated from maternal vagina, E. coli and Staphylococcus aureus were consistent with the results from neonatal blood culture in EONS.

CONCLUSIONS

Our data implicate a possible association between gram-negative bacteria colonization and infertility treatment and suggest that maternal vaginal colonization may be associated with EONS of neonates in high-risk pregnancy.

Obstetric and gynecological diseases and complications resulting from vaginal dysbacteriosis

Accurate knowledge of the composition and ecology of vaginal microbial environment of a healthy woman is necessary for the understanding of normal flora and how to reduce the risk for diseases. Vagina and its microflora form a balanced ecosystem in which dominated bacteria are vaginal lactobacilli. There are dynamic changes in this ecosystem having structure and composition depending on many factors. The term dysbacteriosis defines any movement outside the normal range for the given biotope of obligate and/or facultative microflora. Such a change in the quantity and quality of the respective microbial balance is fraught with danger and requires correction and recovery. The purpose of this overview is to examine obstetric and gynecological diseases that can cause vaginal impaired microbial balance. Vaginal dysbacteriosis is a cause, predecessor, and often also consequence of vaginal infections. In essence, any vaginal infection can be seen as dysbacteriosis, developed to the most severe extent. Here, there is a dominant microorganism other than lactic acid bacteria in the vagina (clinically manifested or not, respectively), depletion of defense mechanisms of the vagina associated with the shift of lactobacilli from their dominant role in the vaginal balance, decrease in their number and species diversity, and a resulting change in the healthy status of the vagina. Vaginal dysbacteriosis can be found in pathogenetic mechanism, whereby many obstetric and gynecological diseases develop. Most of these diseases lead directly to increased maternal and infant morbidity and mortality, so it is important to understand the reasons for them and the arrangements for their prevention.

The prevalence of vaginal microorganisms in pregnant women with preterm labor and preterm birth

Background

To investigate the risk factors for vaginal infections and antimicrobial susceptibilities of vaginal microorganisms among women who experienced preterm birth (PTB), we compared the prevalence of vaginal microorganisms between women who experienced preterm labor (PTL) without preterm delivery and spontaneous PTB.

Methods

Vaginal swab specimens from 126 pregnant women who experienced PTL were tested for group B streptococcus (GBS), Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum, Chlamydia trachomatis, Trichomonas vaginalis, Neisseria gonorrhoeae, Treponema pallidum, herpes simplex virus (HSV) I and II, and bacterial vaginosis. A control group of 91 pregnant women was tested for GBS. Antimicrobial susceptibility tests were performed for GBS, M. hominis, and U. urealyticum.

Results

The overall detection rates for each microorganism were: U. urealyticum, 62.7%; M. hominis, 12.7%; GBS, 7.9%; C. trachomatis, 2.4%; and HSV type II, 0.8%. The colonization rate of GBS in control group was 17.6%. The prevalence of GBS, M. hominis, and U. urealyticum in PTL without preterm delivery and spontaneous PTB were 3.8% and 8.7% (relative risk [RR], 2.26), 3.8% and 17.3% (RR, 4.52), and 53.8% and 60.9% (RR, 1.13), respectively, showing no significant difference between the 2 groups. The detection rate of M. hominis by PCR was higher than that by culture method (11.1% vs. 4.0%, P=0.010). The detection rates of U. urealyticum by PCR and culture method were 16.7% and 57.1%, respectively.

Conclusions

There was no significant difference in the prevalence of GBS, M. hominis, and U. urealyticum between the spontaneous PTB and PTL without preterm delivery groups.

Normal vaginal flora, disorders and application of probiotics in pregnancy

PURPOSE

To assess the effectiveness of vaginal administration of the probiotic Lactobacillus rhamnosus BMX 54 in preventing the occurrence of abnormal vaginal flora and the alteration of parameters relevant to the progression of pregnancy.

METHODS

Sixty pregnant women were assigned randomly to the untreated arm of the study (n = 30) or received (n = 30) vaginal application of one tablet containing Lactobacillus rhamnosus BMX 54, once a week for 12 weeks. Every 4 weeks (T0-T3), vaginal and cervical swabs were collected and pH, and quantity and quality of vaginal discharge measured as well as consistency, length and dilatation of cervix, and level of the presenting part of the foetus relative to interspinous diameter.

RESULTS

In untreated women, there was a significant trend towards increase in the presence of pathogenic microorganisms in the vaginal and/or cervical swabs (p < 0.05), and in average pH values (p < 0.05), amount (p < 0.05) and "whiff test" positivity (p < 0.05) of vaginal discharge. Significant trend was also found for decrease in length (p < 0.0001) and increase in dilatation (p < 0.05) of cervix, as well as for lower position of the foetus (p < 0.0001). In the group treated with Lactobacillus rhamnosus BMX 54, none of these values significantly changed throughout the observation period, with the exception of cervical length that was significantly decreased at T3 (p < 0.01).

CONCLUSIONS

During pregnancy, vaginal administration of Lactobacillus rhamnosus BMX 54 is effective in preventing the development of abnormal vaginal microflora, lowering of the presenting part of the foetus and modifying cervical parameters that could represent risk factors of vulnerability to preterm delivery.

The prevalence of urogenital infections in pregnant women experiencing preterm and full-term labor

Urogenital infections are extremely prevalent during pregnancy and are an important cause of premature labor. However, the prevalence of urogenital infections during childbirth is not well known. Objective. Identify urogenital infections present at the beginning of labor in both full-term and preterm pregnancies. Study Design. Ninety-four women were admitted to the inpatient maternity clinic of the Federal University of Rio Grande do Norte (UFRN). In total, 49 women in preterm labor and 45 women in full-term labor were included in the study, and samples of urinary, vaginal, and perianal material were collected for microbiological analysis. Results. The prevalences of general infections in the preterm labor group and the full-term labor group were 49.0% and 53.3% (P = 0.8300), respectively. Urogenital infections in the preterm and full-term labor groups included urinary tract infection in 36.7% and 22.2% of women, vaginal candidiasis in 20.4% and 28.9% of women, bacterial vaginosis in 34.7% and 28.9% of women, and group B streptococcus in 6.1% and 15.6% of women, respectively. Conclusions. Urogenital infections were prevalent in women in preterm labor and full-term labor; however, significant differences between the groups were not observed.

Treatment of abnormal vaginal flora in early pregnancy with clindamycin for the prevention of spontaneous preterm birth: a systematic review and metaanalysis

The purpose of this study was to determine whether the administration of clindamycin to women with abnormal vaginal flora at <22 weeks of gestation reduces the risk of preterm birth and late miscarriage. We conducted a systematic review and metaanalysis of randomized controlled trials of the early administration of clindamycin to women with abnormal vaginal flora at <22 weeks of gestation. Five trials that comprised 2346 women were included. Clindamycin that was administered at <22 weeks of gestation was associated with a significantly reduced risk of preterm birth at <37 weeks of gestation and late miscarriage. There were no overall differences in the risk of preterm birth at <33 weeks of gestation, low birthweight, very low birthweight, admission to neonatal intensive care unit, stillbirth, peripartum infection, and adverse effects. Clindamycin in early pregnancy in women with abnormal vaginal flora reduces the risk of spontaneous preterm birth at <37 weeks of gestation and late miscarriage. There is evidence to justify further randomized controlled trials of clindamycin for the prevention of preterm birth. However, a deeper understanding of the vaginal microbiome, mucosal immunity, and the biology of BV will be needed to inform the design of such trials.

[Peritonitis due to post-myomectomy Mycoplasma hominis infection]

A 36-year-old woman undergoing a myomectomy developed postoperative surgical-saite peritonitis and hematoma. Eight days postoperatively, she developed a 38 degrees C-plus fever and accumulated ascites, with fever unchanged despite antimicrobial beta-lactams therapy. Following transvaginal ascitic drainage, her fever disappeared. Recurrent 38 degrees C fever and inflammation were cured by clindamycin of 1.2 g/day. M. hominis detected from ascites drainage was considered the primary causative organism. Nongenito-urinary M. hominis infection is often difficult to detect, as in our case. Gram staining, for example, is not useful in ascertaining small organisms such as Mycoplasma spp. having no cell walls to stain. M. hominis grows slowly, requiring over three days to form colonies on blood agar plates, requiring time to identify pathogens. We report case showing the importance of suspecting M. hominis of causing gynecological surgical-site infection. When common bacterial pathogen cultures remain negative and when empiric beta-lactam antibiotic treatment is ineffective, M. hominis should be suspected. In conclusion, M. hominis should be considered a causative following myomectomy resection.

C-reactive protein levels at pre-/post-indicated cervical cerclage predict very preterm birth

AIMS

To investigate the relation between serum levels of C-reactive protein (CRP) at pre-/post-cerclage points and preterm birth at <33 weeks of gestation in women with indicated cervical cerclage (CC).

METHODS

Fifty-eight women with CC indicated for a short or soft cervix, but no visible or protruding fetal membranes into the vagina, between 17 and 26 weeks of gestation, were reviewed. Serum CRP levels were examined three times: just before cerclage, and on day 1 and day 2 post-cerclage.

RESULTS

Serum CRP levels on day 1 and day 2, but not just before cerclage, predicted the occurrence of very preterm birth. In women with cervical dilatation of <3.0 cm, serum CRP levels on post-cerclage day 1 were associated with the increase of very preterm birth [CRP ≥1.5 mg/dL vs. <1.5 mg/dL: 4/5 (80%) vs. 8/31 (26%), P=0.033]. In women with cervical dilatation of <3.0 cm, serum CRP ≥3.0 mg/dL on post-cerclage day 2 was also associated with the increase of very preterm birth.

CONCLUSION

In women with indicated CC between 17 and 26 weeks of gestation, increased levels of serum CRP on post-cerclage day 1 or 2 might be ominous signs for very preterm birth.

Non-surgical management of post-cesarean uterine infection with marked myometrial gas formation

Gas in an infected organ generally indicates a severe infection, often requiring surgery; however, data are lacking as to post-cesarean gas-forming uterine infection. A 27-year-old Japanese primigravida underwent a difficult cesarean section, after which a high fever continued. Computed tomography (CT) revealed marked gas in the uterine anterior myometrium. Diagnosing this condition as post-cesarean uterine scar infection, we recommended surgical intervention, that is, hysterectomy or at least drainage; however, the patient refused it. Considering the patient's desire and lack of organ-failure signs, we employed intensive antibiotic treatment for 6 weeks. Serial CT indicated a gradual decrement in the gas amount and she recovered completely after 8 weeks. This case suggests that surgical procedure may not always be necessary for post-cesarean gas-forming uterine infection and CT may be useful to detect/follow this condition.

Statistical model predicting a short duration to birth in women with preterm labor at 22-35 weeks' gestation: the importance of large vaginal Gram-positive rods

AIMS

To identify risk factors for a short interval to birth in women with preterm labor, and to construct a statistical model to predict birth within seven days from the diagnosis of preterm labor at 22-35 weeks of gestation.

METHODS

Vaginal flora was obtained from 126 singleton pregnant women hospitalized for preterm labor at 22-35 weeks' gestation. The amount of vaginal large Gram-positive rods (GPR) was counted in a bright field under x400 magnification and classified semiquantitively as loss of GPRs, decreased GPRs (<10), and normal flora (10 or more). The effects of vaginal GPRs, cervical dilatation, and previous history of preterm birth on the subsequent occurrence of birth were analyzed using proportional hazards model, and the effects on birth within seven days from the diagnosis of preterm labor were analyzed using multivariate logistic regression.

RESULTS

Fifty-four women (42.9%) delivered preterm. Both loss of GPRs and decreased GPRs were independent risk factors for a short interval from threatened preterm labor to birth, after adjusting the effect of cervical dilatation and past history of preterm birth (hazard ratio 3.4 [95% CI 2.0-5.5] and 2.0 [95% CI 1.1-3.6], respectively). Cervical dilatation of <4.0 cm and 2.0-3.9 cm, and past history of preterm birth were also independent risk factors for a short interval to birth. Loss of GPRs and decreased GPRs, and cervical dilatation of <4.0 cm and 2.0-3.9 cm were independently associated with birth within seven days from the diagnosis of preterm labor (OR 26 [95% CI 5.3-130], 11 [1.9-69], 76 [8.0-720], and 6.4 [1.5-27], respectively).

CONCLUSIONS

Loss of GPRs and decreased GPRs may be independently important for developing birth in women with preterm labor.

Abscess formation due to Mycoplasma hominis infection after cesarean section

A 27-year-old female patient underwent cesarean section and a postoperative hematoma occurred at the site of the uterine incision. The patient underwent relaparotomy to remove the hematoma. Four days later she developed a fever of over 39 degrees C and an abscess had formed at the site. Despite therapy with several antimicrobial agents, her fever persisted. Consequently, she underwent transvaginal abscess drainage, after which she promptly became afebrile. Mycoplasma hominis was considered to be the primary causative organism. There are two reasons that could explain why the wound infection became serious: (i) M. hominis is resistant to several antimicrobial agents that are usually used to treat obstetric infections; and (ii) a long time is required to identify the pathogen. In conclusion, M. hominis should be considered as a causative organism if an antimicrobial-resistant infection occurs at the surgical site after a cesarean section.

Preterm labor and bacterial vaginosis-associated bacteria among urban women

AIMS

Bacterial vaginosis (BV) affects millions of women, is extremely prevalent and is frequently chronic. We recognize numerous microbiologic variations among women with BV and this variability may explain the limited effectiveness of metronidazole in curing BV and/or reducing the risk of spontaneous preterm birth (SPTB) among BV-positive pregnant women. We assessed the independent role of seven common BV-associated bacteria on the risk of spontaneous preterm birth (SPTB) among urban pregnant women.

METHODS

This prospective cohort study was conducted within an urban obstetrics practice at Temple University Hospital in Philadelphia, PA. Fifty pregnant women with documented singleton pregnancies between 25-36 weeks' gestation from February 2007 through June 2007 who presented to the Labor and Delivery Unit for evaluation of uterine contractions/preterm labor were enrolled.

RESULTS

We found that high median levels of Gardnerella vaginalis and low median levels of Lactobacillus crispatus were significantly predictive of SPTB. Slightly higher levels of Megasphaera-like species were also found among the group of women experiencing a SPTB during the follow-up period.

CONCLUSIONS

Further identification of the individual attributable risk for separate BV-associated bacteria may be most useful in developing successful treatments to prevent SPTB among BV positive women.

Correlations of selected vaginal cytokine levels with pregnancy-related traits in women with bacterial vaginosis and mycoplasmas

The aim of this study was to examine correlations between vaginal inflammatory cytokines (IL-1alpha, IL-1beta, IL-6 and IL-8) and pregnancy-related traits (gestational age, birth-weight, BMI, weight gain during pregnancy and vaginal pH). Differences in correlation coefficients were examined among bacterial vaginosis (BV) status and the presence or absence of mycoplasmas. A total of 105 women between the 22nd and 34th week of pregnancy were enrolled in this study. There was a strong negative correlation between IL-1alpha and weight gain during pregnancy (r=-0.877, p<0.001) and a strong positive correlation between IL-6 and BMI (r=0.670, p=0.024) in women with normal vaginal flora and mycoplasmas. These correlations were not present in women who had normal flora and no mycoplasmas. In women with BV and no mycoplasmas, there were significant correlations of gestational age with IL-6 (r=0.727, p=0.027) and IL-8 (r=0.689, p=0.040); however, these correlations were not significant in women with mycoplasmas. Our findings support the conclusion that correlations between inflammatory cytokines and pregnancy-related traits are dependent on context, suggesting that expression is labile. In particular, BMI and gestational age correlation differs depending on BV status and the presence or absence of BV-related mycoplasmas such as Mycoplasma hominis and Ureaplasma urealyticum.

Association between Lactobacillus species and bacterial vaginosis-related bacteria, and bacterial vaginosis scores in pregnant Japanese women

Background

Bacterial vaginosis (BV), the etiology of which is still uncertain, increases the risk of preterm birth. Recent PCR-based studies suggested that BV is associated with complex vaginal bacterial communities, including many newly recognized bacterial species in non-pregnant women.

Methods

To examine whether these bacteria are also involved in BV in pregnant Japanese women, vaginal fluid samples were taken from 132 women, classified as normal (n = 98), intermediate (n = 21), or BV (n = 13) using the Nugent gram stain criteria, and studied. DNA extracted from these samples was analyzed for bacterial sequences of any Lactobacillus, four Lactobacillus species, and four BV-related bacteria by PCR with primers for 16S ribosomal DNA including a universal Lactobacillus primer, Lactobacillus species-specific primers for L. crispatus, L. jensenii, L. gasseri, and L. iners, and BV-related bacterium-specific primers for BVAB2, Megasphaera, Leptotrichia, and Eggerthella-like bacterium.

Results

The prevalences of L. crispatus, L. jensenii, and L. gasseri were significantly higher, while those of BVAB2, Megasphaera, Leptotrichia, and Eggerthella-like bacterium were significantly lower in the normal group than in the BV group. Unlike other Lactobacillus species, the prevalence of L. iners did not differ between the three groups and women with L. iners were significantly more likely to have BVAB2, Megasphaera, Leptotrichia, and Eggerthella-like bacterium. Linear regression analysis revealed associations of BVAB2 and Megasphaera with Nugent score, and multivariate regression analyses suggested a close relationship between Eggerthella-like bacterium and BV.

Conclusion

The BV-related bacteria, including BVAB2, Megasphaera, Leptotrichia, and Eggerthella-like bacterium, are common in the vagina of pregnant Japanese women with BV. The presence of L. iners may be correlated with vaginal colonization by these BV-related bacteria.

Association between preterm birth and vaginal colonization by mycoplasmas in early pregnancy

To examine the association between colonization by two newly classified species of genital ureaplasmas (Ureaplasma parvum and U. urealyticum) in early pregnancy and subsequent late abortion or preterm birth at <34 weeks of gestation, four species of genital mycoplasmas--Mycoplasma genitalium, M. hominis, U. parvum, and U. urealyticum--as well as Chlamydia trachomatis and Neisseria gonorrhoeae were examined by PCR-based methods in a prospective cohort study of 877 women with singleton pregnancies at <11 weeks of gestation. Antibiotics were used only in cases in which C. trachomatis and/or N. gonorrhoeae was detected. Multivariate logistic-regression analysis was used to assess independent risk factors after taking maternal low body weight and past history of preterm birth into account. M. genitalium, M. hominis, U. parvum, U. urealyticum, C. trachomatis, and N. gonorrhoeae were detected in 0.8%, 11.2%, 52.0%, 8.7%, 3.2%, and 0.1% of these 877 women, respectively. Twenty-one (2.4%) women experienced late abortion or preterm birth at <34 weeks of gestation. Three factors-detection of U. parvum in the vagina (odds ratio [OR], 3.0; 95% confidence interval [CI], 1.1 to 8.5); use of antibiotics, such as penicillin and cefatrizine, for incidental inflammatory complications before 22 weeks of gestation (OR, 4.2; 95% CI, 1.6 to 10.0); and past history of preterm birth (OR, 10.4; 95% CI, 2.7 to 40.5)-were independently associated with late abortion and preterm birth. In conclusion, vaginal colonization with U. parvum, but not U. urealyticum, is associated with late abortion or early preterm birth.

Hydrogen peroxide-producingLactobacilliin the vaginal flora of pregnant women with preterm labor with intact membranes

OBJECTIVES

To investigate the role of vaginal infection in preterm delivery, we studied characteristics of vaginal discharge related to hydrogen peroxide-producing Lactobacilli.

METHODS

Vaginal specimens were obtained from 66 women with normal pregnancy and 30 women with preterm labor with intact membranes. pH, leukocyte counts on wet smear, and scores by Nugent criteria on Gram stain were measured. Lactobacilli were tested for their production of hydrogen peroxide.

RESULTS

Leukocyte levels in wet smears and Nugent scores of Gram-stained smear of women with preterm labor with intact membranes were significantly higher than those of normal pregnant women (P<0.01, P<0.05). Hydrogen peroxide-producing Lactobacilli levels in the vaginal flora of women with preterm labor with intact membranes were significantly lower (P<0.01).

CONCLUSION

Distribution of hydrogen peroxide-producing Lactobacilli in vaginal flora as defense factors for infection may have an important role in the pathophysiology of preterm labor.

Relationship between cervical mucus interleukin-8 concentrations and vaginal bacteria in pregnancy

PROBLEM

High interleukin (IL)-8 concentration in cervical mucus in the second trimester is a risk factor for premature birth. We investigated the relationship between vaginal pathogens and IL-8 in cervical mucus.

METHOD OF STUDY

In 501 women with single pregnancy, vaginal secretions were cultured for bacteria and cervical mucus IL-8 concentrations were measured between 20 and 24 gestational weeks.

RESULTS

Lactobacillus species were detected in 56.0% of 84 subjects with high IL-8 (> or =377 ng/mL), significantly less often than in 417 subjects with IL-8 below 377 ng/mL (84.7%; P < 0.0001). Anaerobic pathogens were detected in 83.3% of high IL-8 subjects, significantly more often than in normal IL-8 subjects (43.9%; P < 0.0001). By multivariate analysis, cervical IL-8 was significantly high only in subjects without Lactobacillus species; they showed a significantly higher prematurity rate than Lactobacillus-positive subjects.

CONCLUSIONS

Absence of vaginal Lactobacilli was associated with increased cervical IL-8 and increased risk of premature delivery.

Probiotics for mother and child

For the survival of humankind, nothing can be as important as the health of a mother and a child. As the world's population grows to more than 6 billion, it might seem ridiculous to suggest that any real threat exists to the human species. Diseases have long ravaged populations, as have wars, poverty, and malnutrition. Life today is no different with new and emerging diseases such as SARS and Mad Cow Disease leaving a trail of concern around the planet. All that being said, the AIDS crisis is threatening humans like no other. In countries such as Botswana, close to half the population of pregnant women is infected. Of great concern, the disease is now prevalent among women and teenage girls, threatening not only their lives but those of their offspring. Efforts to control this spread are quite abysmal, albeit well intentioned. Likewise, the death of a child every 15 seconds from diarrheal disease is not being addressed with the same vigor as SARS, even though the risk of dying from the latter for most people is similar to being struck by lightning. In the end, it is the economy and politics that dictate health spending. Image and perception are everything. While deaths mount among women and children from AIDS and other infections, the potential to intervene with a low-risk natural concept of probiotics seemed all too distant. As evidence mounts of the attributes of certain probiotic strains to treat diarrhea and reduce the risk of urogenital and other diseases, the developing world has failed to embrace it, support its evaluation and implementation, and take it to where it is needed the most. In this review, the case for and against probiotics for urogenital and intestinal infections is presented based on current literature. The story is far from complete, but the potential for improving the health of the mother and child is significant. United Nations and World Health Organization guidelines have now been developed to vanquish the unproved marketing hype products that have given probiotics a bad name. It is now up to science to deliver the remedies, and to society to make sure that only proven products reach the marketplace and the people in most need.

Cervical immunoglobulin A and altered vaginal flora in pregnant women with threatened preterm delivery

The aim of our study was to investigate the cervical immunoglobulin A concentration in women with threatened preterm delivery. Immunoglobulin A concentration in the cervical mucus of 80 women with symptoms of preterm delivery was measured using radial immunodiffusion. The results were compared with those of 60 healthy pregnant women. Concentrations of immunoglobulins in maternal serum were also measured. There was no significant difference of cervical immunoglobulin A (IgA) concentration between women with threatened preterm delivery and controls: 53.98 (0.0-189.7) mg/l vs. 61.7 (1.4-400.9; p<0.4) mg/l (median, range). The median of cervical IgA levels in the group of threatened preterm delivery did not differ significantly between patients delivered preterm (n=34) or at term (n=46): 38.3 (0.0-187.9) vs. 65.7 (1.4-189.7; p<0.2) mg/l. Women with a normal vaginal flora showed a significantly higher cervical IgA concentration than those with a pathological colonization: 72.7 (0.0-187.9) vs. 42.5 (0.0-189.7) mg/l. Patients with a pathological vaginal smear and preterm delivery had the lowest IgA levels (35.0; 0.0-187.9 mg/l). Measurement of cervical IgA concentration does not differentiate between women who deliver before or at term.

Identification and H(2)O(2) production of vaginal lactobacilli from pregnant women at high risk of preterm birth and relation with outcome

Lactobacilli, principally the strains that are hydrogen peroxide (H(2)O(2)) producing, may have a protective effect against vaginal colonization by pathogenic species such as those that cause bacterial vaginosis. Previous reports have also suggested that H(2)O(2)-producing lactobacilli in the vagina may protect pregnant women against ascending infection of the chorioamniotic membranes and uterine cavity. We report the identification and H(2)O(2) production of lactobacilli isolated from vaginal swabs collected at 20 weeks' gestation from a population of pregnant women at high risk of preterm birth. We also report the correlation between identification and H(2)O(2) production in relation to the outcomes of chorioamnionitis and preterm birth. Lactobacilli were identified by partial 16S rRNA gene sequencing. H(2)O(2) production by isolates was determined by a semiquantitative method. The most commonly isolated species were L. crispatus, L. gasseri, L. vaginalis and L. jensenii. Amounts of H(2)O(2) produced by lactobacilli varied widely. The presence of lactobacilli producing high levels of H(2)O(2) in the vagina of this population of pregnant women was associated with a reduced risk of bacterial vaginosis at 20 weeks' gestation and subsequent chorioamnionitis. L. jensenii and L. vaginalis produced the highest levels of H(2)O(2). We postulate that H(2)O(2)-producing lactobacilli are able to reduce the incidence of ascending infections of the uterus and the subsequent production of proinflammatory molecules which are important in the pathogenesis of chorioamnionitis and preterm birth.