Association of abnormal vaginal flora and Ureaplasma species as risk factors for preterm birth: a cohort study

Epidemiological characteristics and clinical antibiotic resistance analysis of Ureaplasma urealyticum infection among women and children in southwest China

BACKGROUND

The aim of this study was to investigate the epidemiological characteristics and antibiotic resistance patterns of Ureaplasma urealyticum (UU) infection among women and children in southwest China.

METHODS

A total of 8,934 specimens, including urogenital swabs and throat swabs were analyzed in this study. All samples were tested using RNA-based Simultaneous Amplification and Testing (SAT) methods. Culture and drug susceptibility tests were performed on UU positive patients.

RESULTS

Among the 8,934 patients, the overall positive rate for UU was 47.92%, with a higher prevalence observed among women of reproductive age and neonates. The majority of UU positive outpatients were women of reproductive age (88.03%), while the majority of UU positive inpatients were neonates (93.99%). Overall, hospitalization rates due to UU infection were significantly higher in neonates than in women. Further analysis among neonatal inpatients revealed a higher incidence of preterm birth and low birth weight in UU positive inpatients (52.75% and 3.65%, respectively) than in UU negative inpatients (44.64% and 2.89%, respectively), especially in very preterm and extremely preterm neonates. Moreover, the incidence rate of bronchopulmonary dysplasia (BPD) among hospitalized neonatal patients was significantly higher in the UU positive group (6.89%) than in the UU negative group (4.18%). The drug susceptibility tests of UU in the neonatology, gynecology and obstetrics departments exhibited consistent sensitivity patterns to antibiotics, with high sensitivity to tetracyclines and macrolides, and low sensitivity to fluoroquinolones. Notably, UU samples collected from the neonatology department exhibited significantly higher sensitivity to azithromycin and erythromycin (93.8% and 92.9%, respectively) than those collected from the gynecology and obstetrics departments.

CONCLUSIONS

This study enhances our understanding of the current epidemiological characteristics and antibiotic resistance patterns of UU infection among women and children in southwest China. These findings can aid in the development of more effective intervention, prevention and treatment strategies for UU infection.

Prevalence of genital Mycoplasma in pregnancies with shortened cervix

OBJECTIVE

To determine whether colonisation with genital Mycoplasma species (spp.) in patients presenting with a shortened cervix before 34th week of pregnancy is associated with preterm birth.

METHODS

The collection of this retrospective study consisted of 100 pregnant women who presented to a German Tertiary Perinatal Center between 2017 and 2020 due to a shortened cervix defined as a cervical length of 25 mm or shorter measured by transvaginal ultrasound before 34 weeks of gestation. At the time of admission, gestational age ranged from 18 + 4 to 33 + 3 weeks (+ days) of pregnancy. All patients underwent urine polymerase chain reaction (PCR) for genital Mycoplasma [Ureaplasma (U.) urealyticum, U. parvum, M. hominis or M. genitalium]. Patients who were tested positive underwent a therapy with macrolides (azithromycin or clarithromycin).

RESULTS

37% of the patients were positive for Ureaplasma spp., whereas 5% (5 patients) were Mycoplasma spp.-positive. All the latter were simultaneously colonised with Ureaplasma spp. Ureaplasma-positive patients were significantly younger than those who were tested negative. Median maternal age at examination was 30 years (a) versus 31a (p = 0.04). There was no difference between Ureaplasma-positive and -negative patients regarding median maternal body mass index (BMI) (kg/m2) (23.4 versus 22.3, p = 0.41), cervical length at admission (mm) (15 versus 17, p = 0.17), gestational age at examination (days, d) (198 versus 197, p = 0.97) or gestational age at birth (d) (250 versus 257, p = 0.33), respectively. Comparing U. parvum-positive and U. urealyticum-positive patients, there was some weak indication that U. parvum-positive patients may get a shortening of the cervix earlier in pregnancy, as the median gestational age at examination was 196d versus 215d (p = 0.06). Regarding Mycoplasma-positive and -negative patients, there was no difference in all examined parameters.

CONCLUSIONS

Overall, one-third of all women in our study with a shortened cervix before 34th week of pregnancy were colonised with genital Mycoplasma spp. We were able to show that pregnant women, who were treated with antibiotics when tested positive for genital Mycoplasma, gave birth at the same gestational age as patients with a shortened cervix without detected Mycoplasma. This raises the question of whether routine testing and early antibiotic treatment should be established in prenatal care.

Does vaginal bacterial colonization contribute to preterm birth in women with asymptomatic shortened cervix?

PURPOSE

The aim of this study is to describe the typical microbial spectrum and the influence of distinct vaginal infections on preterm birth in pregnancies affected by cervical incompetence.

METHODS

327 patients were admitted because of asymptomatic shortening of the cervix in the second and third trimester of pregnancy. Clinical data such as age, cervical length, gestational age at admission and at delivery and vaginal microbiologic findings were collected and analyzed.

RESULTS

The spectrum of germs in the vagina revealed seven different distinct species; the most common bacteria were Ureaplasma spp. and E. coli. In 327 included patients, 217 revealed a bacterial colonization, 110 did not. Most common bacteria in women with preterm birth before 34 weeks were Ureaplasma spp., while E. coli was most common in women undergoing preterm birth after 34 weeks. Nevertheless, the rates of occurrence of these bacterial taxa were not significantly different between who underwent preterm birth to those who did not.

CONCLUSIONS

This study gives an overview over the vaginal bacterial colonization in pregnant women with cervical incompetence. The clinical relevance of vaginal bacterial colonization remains unclear.

Abnormal Vaginal Flora in Cervical Incompetence Patients - the Impact of Escherichia coli

The purpose of this study was to investigate the prevalence of abnormal vaginal colonization in women with cervical incompetence and to analyze its impact on obstetric and neonatal outcomes and placental inflammation. We included 138 pregnant women diagnosed with cervical incompetence and delivered in our hospital. Patients with major fetal anomaly or multifetal pregnancy were excluded. Upper vaginal culture was performed on the day of admission. A total of 60.9% (84/138) of cervical incompetence patients had abnormal bacterial colonization, and Escherichia coli (E. coli) was the most common colonized pathogen (33.3%, 46/138). The positive vaginal E. coli group had a higher rate of prior preterm birth (p = 0.021) and an earlier gestational age at which cervical incompetence was diagnosed (p < 0.01) than the negative group. The positive vaginal E. coli group had higher rates of clinical chorioamnionitis (p = 0.008) and subchorionic microabscess of the placenta (p = 0.012). Importantly, the positive vaginal E. coli group had significantly higher rates of proven early-onset neonatal sepsis (EONS) (p = 0.046), necrotizing enterocolitis (NEC) (p = 0.001), and neonatal mortality (p = 0.023). After adjusting for confounding variables, the positive vaginal E. coli group had significantly higher risk for proven EONS (OR: 3.853, 95% CI: 1.056-14.055) and NEC (OR: 12.410, 95% CI: 1.290-119.351). In conclusion, E. coli was the most common vaginal microorganism isolated from patients with cervical incompetence. Maternal vaginal E. coli colonization was associated with adverse neonatal outcomes including proven EONS and NEC and was characterized by a higher rate of placental subchorionic microabscess.

Systematic review and meta-analysis of maternal and fetal outcomes among pregnant women with bacterial vaginosis

BACKGROUND

Women of childbearing age are commonly affected by bacterial vaginosis (BV). Maternal-fetal outcomes associated with BV during pregnancy can be fatal for both the mother and the newborn.

AIM

To identify maternal and fetal outcomes in pregnant women with BV encountered globally, highlight their prevalence, and identify maternal-fetal outcomes associated with BV.

METHODS

The databases Embase, PubMed, Web of Science and Global Index Medicus were searched from inception until December 2022. No restrictions on time or geographical location were imposed when searching for published articles that examined maternal-fetal outcomes in pregnant women with BV. A random effects model was used to perform the meta-analysis. Sources of heterogeneity were investigated using subgroup analysis, and publication bias was assessed using funnel plots and Egger tests.

FINDINGS

In total, 26 of the 8983 articles retrieved from the databases met the inclusion criteria and were included in this study. Twenty-two maternal outcomes and 22 fetal outcomes were recorded among pregnant women with BV worldwide. This study determined the prevalence of maternal-fetal outcomes reported in three or more studies. Among fetal outcomes, preterm birth (PTB) had the highest prevalence [17.9%, 95% confidence interval (CI) 13-23.3%], followed by mechanical ventilation (15.2%, 95% CI 0-45.9%), low birth weight (LBW) (14.2%, 95% CI 9.1-20.1%) and neonatal intensive care unit admission (11.2%, 95% CI 0-53.5%). BV was associated with PTB [odds ratio (OR) 1.76, 95% CI 1.32-2.35], LBW (OR 1.73, 95% CI 1.41-2.12) and birth asphyxia (OR 2.90, 95% CI 1.13-7.46). Among maternal outcomes, premature rupture of membranes (PROM) had the highest prevalence (13.2%, 95% CI 6.1-22.3%). BV was associated with the following maternal outcomes: intrauterine infection (OR 2.26, 95% CI 1.44-3.56), miscarriage (OR 2.34, 95% CI 1.18-4.64) and PROM (OR 2.59, 95% CI 1.39-4.82). Maternal and fetal outcomes were most prevalent in women whose BV was diagnosed using the Amsel criteria (37.2%, 95% CI 23-52.6%) and in the third trimester (29.6%, 95% CI 21.2-38.8%). Although reported in fewer than three studies, some maternal-fetal outcomes are highly prevalent, such as respiratory distress (76.67%, 95% CI 57.72-90.07%), dyspareunia (68.33%, 95% CI 55.04-79.74%) and malodorous discharge (85.00%, 95% CI 73.43-92.90%).

CONCLUSION

BV has been associated with several adverse maternal-fetal outcomes around the world. While BV is a common vaginal infection, the types of maternal-fetal outcomes from pregnant women with BV vary by country.

Maternal Baseline Risk Factors for Abnormal Vaginal Colonisation among High-Risk Pregnant Women and the Association with Adverse Pregnancy Outcomes: A Retrospective Cohort Study

Abnormal vaginal colonisation can lead to adverse pregnancy outcomes such as preterm birth through intra-amniotic inflammation. Despite the concern, little is known about its risk factors and impact in pregnant women at high-risk for spontaneous preterm birth. Thus, we conducted this single-centre retrospective cohort study including 1381 consecutive women who were admitted to the high-risk pregnancy unit. The results of vaginal culture at admission were categorised according to the colonising organism: bacteria (Gram-negative or -positive) and genital mycoplasmas. Maternal baseline socioeconomic, and clinical characteristics, as well as pregnancy, delivery, and neonatal outcomes were compared according to the category. Maternal risk factors for Gram-negative colonisation included advanced maternal age, increased pre-pregnancy BMI, a greater number of past spontaneous abortions, earlier gestational age at admission, and IVF. Gram-positive colonisation was likewise associated with earlier gestational age at admission. Genital mycoplasmal colonisation was associated with a greater number of past induced abortions, a lower level of education completed, and a lower rate of multifetal pregnancy and IVF. The neonates from mothers with Gram-negative colonisation had a greater risk of NICU admission, proven early onset neonatal sepsis, and mortality. However, not Gram-positive bacteria or genital mycoplasma was directly associated with adverse pregnancy outcomes.

Ureaplasma and Prevotella colonization with Lactobacillus abundance during pregnancy facilitates term birth

Ureaplasma and Prevotella infections are well-known bacteria associated with preterm birth. However, with the development of metagenome sequencing techniques, it has been found that not all Ureaplasma and Prevotella colonizations cause preterm birth. The purpose of this study was to determine the association between Ureaplasma and Prevotella colonization with the induction of preterm birth even in the presence of Lactobacillus. In this matched case–control study, a total of 203 pregnant Korean women were selected and their cervicovaginal fluid samples were collected during mid-pregnancy. The microbiome profiles of the cervicovaginal fluid were analyzed using 16S rRNA gene amplification. Sequencing data were processed using QIIME1.9.1. Statistical analyses were performed using R software, and microbiome analysis was performed using the MicrobiomeAnalyst and Calypso software. A positive correlation between Ureaplasma and other genera was highly related to preterm birth, but interestingly, there was a negative correlation with Lactobacillus and term birth, with the same pattern observed with Prevotella. Ureaplasma and Prevotella colonization with Lactobacillus abundance during pregnancy facilitates term birth, although Ureaplasma and Prevotella are associated with preterm birth. Balanced colonization between Lactobacillus and Ureaplasma and Prevotella is important to prevent preterm birth.

Genital infection with Ureaplasma urealyticum and its effect on pregnancy

Chorioamnionitis or intra-amniotic infection is an infection that affects the intrauterine content during pregnancy. Numerous studies have reported vaginal colonization with various types of infectious agents as a risk factor for chorioamnionitis. Although this complication occurs due to the ascending polymicrobial bacterial infection at the time of membrane breakage, it may also occur in pregnant women with intact membranes, mainly due to Ureaplasma urealyticum (U. urealyticum) and Mycoplasma hominis (M. hominis). The main aim of the present study was to identify a region-specific panel of infectious agents that can be used more accurately determine premature birth, as well as the premature rupture of membranes (PROM). Thus, a 10-year retrospective study was conducted. A total of 1,301 pregnant women with PROM and premature birth or spontaneous abortion were included in the study. It was observed that the main infectious agent varied in the five groups analyzed in total. The infectious agent distribution also varied depending on environmental parameters. Ureaplasma was found to be the most frequently detected germ amongst the infectious agents of the vaginal cultures from pregnant women enrolled in the present study, regardless of gestational age. On the whole, the findings of the present study suggest that additional studies are required, in order to confirm that diagnosis and treatment according to laboratory results of vaginal infections with U. urealyticum/M. hominis during the first trimester of pregnancy could prevent premature birth, abortion or chorioamnionitis.

Genital mycoplasma infection and spontaneous preterm birth outcome: a prospective cohort study

OBJECTIVE

To assess the risk of spontaneous preterm birth (sPTB) associated with genital mycoplasma infection in asymptomatic women.

DESIGN

Prospective cohort.

SETTING

Public and private health services in Ribeirão Preto, SP, Brazil.

POPULATION

A cohort of 1349 asymptomatic women with a singleton pregnancy at 20-25 weeks of gestation.

METHODS

Participants completed a sociodemographic and clinical history questionnaire during the prenatal visit and provided cervicovaginal samples for the evaluation of Mycoplasma hominis (Mh), Ureaplasma spp. and bacterial vaginosis (BV). For gestational outcome, information about the delivery was assessed and sPTB was defined as a birth that occurred before 37 weeks of gestation. The association between variables and the risk of sPTB was evaluated using logistic regression analysis to estimate the odds ratios (ORs).

MAIN OUTCOME MEASURES

Genital mycoplasma infection and prematurity.

RESULTS

The prevalence of sPTB and genital mycoplasma was 6.8 and 18%, respectively. The infection was not a risk factor for sPTB (aOR 0.66, 95% CI 0.32-1.35), even when Mh and Ureaplasma spp. were found together (P = 0.83). Pregnant women with genital mycoplasma infections had greater BV (P < 0.0001), but this vaginal microbiota condition was not associated with sPTB (P = 0.35). Regarding the risk factors associated with sPTB, a previous history of sPTB (aOR 12.06, 95% CI 6.21-23.43) and a cervical length of ≤2.5 cm (aOR 3.97, 95% CI 1.67-9.47) were significant.

CONCLUSIONS

Genital mycoplasma infection was not a risk factor for sPTB, even in the presence of other abnormal vaginal microbiota.

TWEETABLE ABSTRACT

Genital mycoplasma infection was not a risk for sPTB, even when associated with bacterial vaginosis (BV).

Intra-amniotic infection and sterile intra-amniotic inflammation in women with preterm labor with intact membranes are associated with a higher rate of Ureaplasma species DNA presence in the cervical fluid

OBJECTIVE

To determine the prevalence of Ureaplasma spp. DNA and its load in the cervical fluid in women with preterm labor with intact membranes (PTL) complicated by intra-amniotic infection (the presence of both microbial invasion of the amniotic cavity and intra-amniotic inflammation) or sterile intra-amniotic inflammation (the presence of intra-amniotic inflammation alone).

METHODS

Overall, 115 women with singleton pregnancies complicated by PTL between gestational ages of 22 + 0 and 34 + 6 weeks were included in this study. Paired amniotic and cervical fluid samples were collected at the time of admission via transabdominal amniocentesis using a Dacron polyester swab. Microbial invasion of the amniotic cavity was diagnosed based on a combination of culture and molecular biology methods. Intra-amniotic inflammation was determined based on the concentration of interleukin-6 in the amniotic fluid. Bacterial and Ureaplasma spp. DNA loads were assessed in the cervical fluid using PCR.

RESULTS

Intra-amniotic infection and sterile inflammation were identified in 14% (16/115) and 25% (29/115) of the women, respectively. Ureaplasma spp. DNA in the cervical fluid was identified in 51% (59/115) of women. The presence of Ureaplasma spp. DNA in the cervical fluid was higher in women with intra-amniotic infection (75% (12/16)) and sterile intra-amniotic inflammation (76% (22/29)) than in women without intra-amniotic inflammation (36% (25/70); p = .0002). Concurrent presence of Ureaplasma spp. and Mycoplasma hominis DNA was higher in women with intra-amniotic infection (42% (5/12)) than women with sterile intra-amniotic inflammation (7% (2/29)) and women without intra-amniotic inflammation (7% (5/70); p = .001). There were no differences in the load of Ureaplasma spp. DNA in the cervical fluid among women with intra-amniotic infection, sterile intra-amniotic inflammation, and those without intra-amniotic inflammation (median values; infection: 1.2 × 10⁴ copies DNA/mL; sterile: 5.0 × 10⁵ copies DNA/mL; without: 8.4 × 10⁴ copies DNA/mL; p = .18).

CONCLUSIONS

In PTL , both forms of intra-amniotic inflammation were associated with a higher prevalence of Ureaplasma spp. DNA in the cervical fluid. The presence of intra-amniotic infection was related to a higher rate of concurrent Ureaplasma spp. and M. hominis DNA in the cervical fluid.

Association between maternal cervicovaginal swab positivity for Ureaplasma spp. or other microorganisms and neonatal respiratory outcome and mortality

OBJECTIVE

We investigated the association between maternal cervicovaginal cultures, its antibiotic treatment, and neonatal outcome.

STUDY DESIGN

This retrospective cohort study enrolled 480 neonates born prior to 32 weeks' gestation. They were divided into groups according to maternal cervicovaginal culture results. Multivariate logistic regression analysis was used to predict neonatal outcome based on maternal culture results, adjusted for perinatal risk factors and neonatal morbidities.

RESULT

Maternal cervicovaginal Ureaplasma colonization was independently associated with bronchopulmonary dysplasia at 36 weeks (BPD) (OR 8.34; 95% CI 1.21-57.45). In neonates with and without maternal cervicovaginal Ureaplasma colonization BPD occurred in 12.3% and 3.8%, respectively. Maternal colonization with other microorganisms was associated with a higher neonatal mortality (p = 0.002), lower gestational age (p = 0.026), and birth weight (p = 0.036).

CONCLUSIONS

This study underscores the role of the maternal cervicovaginal microbiome as a predictor of neonatal outcome. Cervicovaginal Ureaplasma colonization seems not to be an innocent bystander in the multifactorial etiology of BPD.

Risk factors associated with preterm birth: a retrospective study in Mukalla Maternity and Childhood Hospital, Hadhramout Coast/Yemen

Preterm birth (PTB) is a major determinant of neonatal mortality, morbidity and childhood disability. It has long-term adverse consequences for health. The causes of preterm delivery (PTD) are multifactorial. This study was conducted to determine the most common risk factors for PTB at Mukalla Maternity and Childhood (MCH) Hospital, Yemen. A retrospective case-control study was conducted. It involved the records of 100 women with live PTD as cases and 400 women with live term delivery as controls at Mukalla MCH Hospital in 2018. All the data were analysed using the Statistical Package for the Social Sciences (version 24). The statistical relationship between independent variables and PTB was studied by the Chi-square test in bivariate analysis and logistic regression in multivariate analysis. The strength of association was confirmed by using odds ratios (ORs) with a 95% confidence interval (CI). Risk factors with statistically significant association with premature birth were a family history of PTD (adjusted OR [AOR] 2.353; CI 1.3-4.258, p-value 0.005), pre-eclampsia (AOR 4.120; CI 1.818-9.340, p-value 0.001), parity (AOR 2.139; CI 1.249-3.662, p-value 0.006), premature rupture of membranes (AOR 4.161; CI 2.323-7.456, p-value 0.000) and abnormal amniotic fluid volume (AOR 4.534; CI 1.364-15.071, p-value 0.014). An early recognition of preterm risk factors will help medical staff and healthcare workers to identify women with a high-risk pregnancy.

Vaginal Ureaplasma urealyticum or Mycoplasma hominis and preterm delivery in women with threatened preterm labor

Background: Amniotic fluid infection with Ureaplasma urealyticum or Mycoplasma hominis can cause chorioamnionitis and preterm birth. The aim of this study was to examine whether vaginal Ureaplasma urealyticum/Mycoplasma hominis colonization is predictive of preterm delivery in patients exhibiting signs of threatened preterm birth or those with asymptomatic short cervix.Methods: The present retrospective study, which was performed in a perinatal tertiary center, included patients carrying a singleton pregnancy who were referred to the emergency Ob/Gyn unit because of regular preterm uterine contractions and/or short cervical length (<20 mm) at 22-33 weeks of gestation, and in whom a vaginal U. urealyticum/M. hominis examination (Urea-arginine LYO-2, BioMerieux^®) was performed. Univariate and multivariate analyses were performed to assess the association between vaginal U. urealyticum or M. hominis and chorioamnionitis or preterm delivery.Results: The median gestational age of the 94 enrolled patients was 29.9 weeks, and 54 (57%) of the patients were vaginal U. urealyticum/M. hominis-positive. The preterm delivery rate in the positive group was higher than in the negative group (53 versus 25%; p = .007). Vaginal U. urealyticum/M. hominis positivity was found to be an independent risk factor for preterm birth at <37 weeks of gestation (adjusted odds ratio = 4.0, 95% confidence interval, 1.1-15.3) in a multivariate analysis adjusted for age, history of preterm delivery and conization, gestational age, cervical length, presence of vaginal bleeding, vaginal fetal fibronectin and serum C-reactive protein at test. U. urealyticum/M. hominis positivity was not associated with delivery at <34 weeks or chorioamnionitis.Conclusion: A positive vaginal U. urealyticum/M. hominis culture is an independent predictive factor for preterm birth in patients with symptomatic threatened preterm labor and/or short cervix.

The earlier the gestational age, the greater the intensity of the intra-amniotic inflammatory response in women with preterm premature rupture of membranes and amniotic fluid infection by Ureaplasma species

Objectives To determine the relationship between the intensity of the intra-amniotic inflammatory response and the gestational age at the time of diagnosis in cases with preterm premature rupture of membranes (PROM) and intra-amniotic infection caused by Ureaplasma spp. Methods A retrospective cohort study was conducted which included 71 women with preterm PROM and a positive amniotic fluid culture with Ureaplasma spp. Women with mixed intra-amniotic infections were excluded. The study population was classified into three groups according to gestational age: group 1, <26 weeks (extreme preterm PROM, n = 17); group 2, 26.0-33.9 weeks (moderate preterm PROM, n = 39); group 3, 34.0-36.9 weeks (late preterm PROM, n = 15). The intensity of the intra-amniotic and maternal inflammatory response was compared among the three groups. The intensity of the intra-amniotic inflammatory response was assessed by the concentration of amniotic fluid matrix metalloproteinase-8 (MMP-8) and white blood cell (WBC) count. The maternal inflammatory response was assessed by the concentration of C-reactive protein (CRP) and WBC count in maternal blood at the time of amniocentesis. Results (1) The median values of amniotic fluid MMP-8 concentration and WBC count were the highest in the extreme preterm PROM group and the lowest in the late preterm PROM group (P < 0.001 and P = 0.01, respectively); (2) the intensity of the maternal inflammatory response measured by maternal blood WBC count and CRP concentration was not significantly associated with gestational age at the time of diagnosis. Conclusion The earlier the gestational age at the time of PROM, the higher the intensity of the intra-amniotic inflammatory response in women with preterm PROM and intra-amniotic infection caused by Ureaplasma spp.

Vaginal Ureaplasma parvum serovars and spontaneous preterm birth

BACKGROUND

Ureaplasma species (spp) are the bacteria most often isolated from the amniotic cavity of women with preterm labor or preterm premature rupture of membranes; thus, the link between intrauterine Ureaplasma spp infection and adverse pregnancy outcome clearly is established. However, because vaginal Ureaplasma spp colonization is very common in pregnant women, the reason that these microorganisms cause ascending infections in some cases but remain asymptomatic in most pregnancies is not clear. Previous studies suggested an association between vaginal colonization with Ureaplasma parvum as opposed to U urealyticum and preterm delivery. However, because of the high frequency of vaginal Ureaplasma spp colonization during pregnancy, additional risk factors are needed to select a group of women who might benefit from treatment.

OBJECTIVE

To further identify pregnant women who are at increased risk for preterm delivery, the aim of the present study was to investigate U parvum serovar-specific pathogenicity in a large clinical cohort.

STUDY DESIGN

We serotyped 1316 samples that were positive for U parvum using a high-resolution melt polymerase chain reaction assay, and results were correlated with pregnancy outcome.

RESULTS

Within U parvum positive samples, serovar 3 was the most common isolate (43.3%), followed by serovar 6 (31.4%) and serovar 1 (25.2%). There was a significantly increased risk for spontaneous preterm birth at very low (<32 weeks gestation; P<.005) and extremely low (<28 weeks gestation; P<.005) gestational age in the group with vaginal U parvum serovar 3 colonization compared with the control group of pregnant women who tested negative for vaginal Ureaplasma spp colonization. This association was found for neither serovar 1 nor serovar 6. The combination of vaginal U parvum serovar 3 colonization and diagnosis of bacterial vaginosis in early pregnancy or a history of preterm birth further increased the risk for adverse pregnancy outcome.

CONCLUSION

Colonization with U parvum serovar 3, but not serovar 1 or serovar 6, in early pregnancy is associated with preterm delivery at very and extremely low gestational age. The combination of U parvum serovar 3 colonization and a history of preterm birth or bacterial vaginosis further increases the risk for spontaneous preterm birth at low gestational age and may define a target group for therapeutic intervention studies.

Infection-induced thrombin production: a potential novel mechanism for preterm premature rupture of membranes (PPROM)

BACKGROUND

Preterm premature rupture of membranes is a leading contributor to maternal and neonatal morbidity and death. Epidemiologic and experimental studies have demonstrated that thrombin causes fetal membrane weakening and subsequently preterm premature rupture of membranes. Although blood is suspected to be the likely source of thrombin in fetal membranes and amniotic fluid of patients with preterm premature rupture of membranes, this has not been proved. Ureaplasma parvum is emerging as a pathogen involved in prematurity, which includes preterm premature rupture of membranes; however, until now, prothrombin production that has been induced directly by bacteria in fetal membranes has not been described.

OBJECTIVE

This study was designed to investigate whether Ureaplasma parvum exposure can induce prothrombin production in fetal membranes cells.

STUDY DESIGN

Primary fetal membrane cells (amnion epithelial, chorion trophoblast, and decidua stromal) or full-thickness fetal membrane tissue explants from elective, term, uncomplicated cesarean deliveries were harvested. Cells or tissue explants were infected with live Ureaplasma parvum (1×10⁵, 1×10⁶ or 1×10⁷ colony-forming units per milliliter) or lipopolysaccharide (Escherichia coli J5, L-5014; Sigma Chemical Company, St. Louis, MO; 100 ng/mL or 1000 ng/mL) for 24 hours. Tissue explants were fixed for immunohistochemistry staining of thrombin/prothrombin. Fetal membrane cells were fixed for confocal immunofluorescent staining of the biomarkers of fetal membrane cell types and thrombin/prothrombin. Protein and messenger RNA were harvested from the cells and tissue explants for Western blot or quantitative reverse transcription polymerase chain reaction to quantify thrombin/prothrombin protein or messenger RNA production, respectively. Data are presented as mean values ± standard errors of mean. Data were analyzed using 1-way analysis of variance with post hoc Dunnett's test.

RESULTS

Prothrombin production and localization were confirmed by Western blot and immunostainings in all primary fetal membrane cells and tissue explants. Immunofluorescence observations revealed a perinuclear localization of prothrombin in amnion epithelial cells. Localization of prothrombin in chorion and decidua cells was perinuclear and cytoplasmic. Prothrombin messenger RNA and protein expression in fetal membranes were increased significantly by Ureaplasma parvum, but not lipopolysaccharide, treatments in a dose-dependent manner. Specifically, Ureaplasma parvum at a dose of 1×10⁷ colony-forming units/mL significantly increased both prothrombin messenger RNA (fold changes in amnion: 4.1±1.9; chorion: 5.7±4.2; decidua: 10.0±5.4; fetal membrane: 9.2±3.0) and protein expression (fold changes in amnion: 138.0±44.0; chorion: 139.6±15.1; decidua: 56.9±29.1; fetal membrane: 133.1±40.0) compared with untreated control subjects. Ureaplasma parvum at a dose of 1×10⁶ colony-forming units/mL significantly up-regulated prothrombin protein expression in chorion cells (fold change: 54.9±5.3) and prothrombin messenger RNA expression in decidua cells (fold change: 4.4±1.9).

CONCLUSION

Our results demonstrate that prothrombin can be produced directly by fetal membrane amnion, chorion, and decidua cells. Further, prothrombin production can be stimulated by Ureaplasma parvum exposure in fetal membranes. These findings represent a potential novel underlying mechanism of Ureaplasma parvum-induced rupture of fetal membranes.

First Trimester Vaginal Ureaplasma Biovar Colonization and Preterm Birth: Results of a Prospective Multicenter Study

BACKGROUND

While there is a proven association of upper genital tract Ureaplasma infection during pregnancy with adverse pregnancy outcome, the effect of vaginal Ureaplasma colonization on preterm delivery has been controversially debated.

OBJECTIVES

We hypothesized that women with isolation of vaginal U. parvum but not U. urealyticum are at increased risk for spontaneous preterm birth (SPB) compared to women with negative results.

METHODS

A vaginal swab taken between 12 and 14 weeks of gestation was analyzed for the presence of Ureaplasma biovars by PCR in 4,330 pregnant women.

RESULTS

Of the study cohort, 37% were positive for U. parvum, 5.9% for U. urealyticum, and 3.1% for both. The rates of SPB were 10.4% (OR 1.7, 95% CI 1.3, 2.2, p < 0.001) and 8.9% (OR 1.4, 95% CI 0.9, 2.3, p = 0.193) in the groups with isolation of U. parvum and U. urealyticum, respectively, compared to 6.4% in the group with negative PCR results. Multiple logistic regression and interaction analyses showed that vaginal colonization with U. parvum but not U. urealyticum was a statistically significant risk factor for SPB (adjusted OR 1.6, 95% CI 1.2, 2.1, p < 0.001), independent of other risk factors such as bacterial vaginosis and history of SPB.

CONCLUSION

Our study demonstrates a statistically significant and independent association between first-trimester vaginal colonization with U. parvum and subsequent SPB.

Mycoplasma/Ureaplasma infection in pregnancy: to screen or not to screen

Mycoplasmata have been linked to pregnancy complications and neonatal risk. While formerly a limited number of species could be discovered by cultures, molecular biology nowadays discovers both lower quantities and more diverse species, making us realize that mycoplasmata are ubiquitous in the vaginal milieu and do not always pose a danger for pregnant women. As the meaning of mycoplasmata in pregnancy is not clear to many clinicians, we summarized the current knowledge about the meaning of different kinds of mycoplasmata in pregnancy and discuss the potential benefits and disadvantages of treatment. Currently, there is no general rule to screen and treat for mycoplasmata in pregnancy. New techniques seem to indicate that Ureaplasma parvum (Up), which now can be distinguished from U. urealyticum (Uu), may pose an increased risk for preterm birth and bronchopulmonary disease in the preterm neonate. Mycoplasma hominis (Mh) is related to early miscarriages and midtrimester abortions, especially in the presence of abnormal vaginal flora. Mycoplasma genitalium (Mg) is now recognized as a sexually transmitted infection (STI) that is involved in the causation of cervicitis, pelvic inflammatory disease (PID) in non-pregnant, and preterm birth and miscarriages in pregnant women, irrespective of the presence of concurrent other STIs, like Chlamydia or gonorrhoea. Proper studies to test for efficacy and improved pregnancy outcome are scarce and inconclusive. Azythromycin is the standard treatment now, although, for Mg, this may not be sufficient. The role of clarithromycin in clinical practice still has to be established. There is a stringent need for new studies based on molecular diagnostic techniques and randomized treatment protocols with promising and safe antimicrobials.

Applying Precision Public Health to Prevent Preterm Birth

Preterm birth (PTB) is one of the major health-care challenges of our time. Being born too early is associated with major risks to the child with potential for serious consequences in terms of life-long disability and health-care costs. Discovering how to prevent PTB needs to be one of our greatest priorities. Recent advances have provided hope that a percentage of cases known to be related to risk factors may be amenable to prevention; but the majority of cases remain of unknown cause, and there is little chance of prevention. Applying the principle of precision public health may offer opportunities previously unavailable. Presented in this article are ideas that may improve our abilities in the fields of studying the effects of migration and of populations in transition, public health programs, tobacco control, routine measurement of length of the cervix in mid-pregnancy by ultrasound imaging, prevention of non-medically indicated late PTB, identification of pregnant women for whom treatment of vaginal infection may be of benefit, and screening by genetics and other “omics.” Opening new research in these fields, and viewing these clinical problems through a prism of precision public health, may produce benefits that will affect the lives of large numbers of people.

The Role of Progesterone and a Novel Progesterone Receptor, Progesterone Receptor Membrane Component 1, in the Inflammatory Response of Fetal Membranes to Ureaplasma parvum Infection

Ureaplasma parvum (U. parvum) is gaining recognition as an important pathogen for chorioamnionitis and preterm premature rupture of membranes. We aimed to investigate the roles of progesterone (P4) and a novel progesterone receptor, progesterone receptor membrane component 1 (PGRMC1), in the response of fetal membranes to U. parvum. Fetal membrane cells (amnion, chorion and decidua) were isolated and confirmed to be free of Mycoplasmataceae. Cells were treated with U. parvum (5x10⁶ CFU), and adherence was quantified by qPCR. Amnion and chorion cells were transfected with scrambled siRNA or validated PGRMC1 siRNA for 72h. Cells were then treated with U. parvum for 4h with or without pretreatment with P4 (10⁻⁷ M) or ethanol for 1h. Interleukin-8 (IL-8), matrix metalloproteinase 9 (MMP9) and cyclooxygenase (COX-2) mRNA expression were quantified by qRT-PCR. Culture medium was harvested and analyzed for IL-8 and prostaglandin (PGE₂) secretion by ELISA and MMP9 activity by zymography. U. parvum had a mean adherence of 15.0±0.6%, 16.9± 3.7% and 4.7±0.3% in cultured amnion, chorion and decidua cells, respectively. Exposure to U. parvum elicited significant inflammatory responses including induction of IL-8, COX-2, PGE2 and MMP9. A possible role of PGRMC1 was identified in the inhibition of U. parvum-stimulated COX-2 and MMP9 mRNA expression in chorion cells and MMP9 activity in amnion cells. On the other hand, it might enhance the U. parvum-stimulated IL-8 protein secretion in amnion cells. P4, mediated through PGRMC1, significantly inhibited U. Parvum-induced MMP9 mRNA and COX-2 mRNA expression in chorion cells. P4 appeared to attenuate U. parvum induced IL-8 mRNA expression in chorion cells, but this P4 effect might not mediated through PGRMC1. In summary, U. parvum preferentially adheres to and induces inflammatory responses in chorion and amnion cells. P4 and PGRMC1 appear to differentially modulate the inflammatory responses induced by U. parvum among amnion and chorion cells.

Ureaplasma parvum genotype, combined vaginal colonisation with Candida albicans, and spontaneous preterm birth in an Australian cohort of pregnant women

BACKGROUND

Detection of Ureaplasma, Mycoplasma and Candida spp. in the vagina during pregnancy has previously been associated with preterm birth (PTB). However, the prevalence of these microorganisms and the associated obstetric risks (likely to be population-specific) have not been determined in Australian women; furthermore, in the case of Ureaplasma spp., very few studies have attempted characterisation at the species level and none have examined genotype/serovar status to further refine risk assessment.

METHODS

In order to address these issues we sampled the vaginal fluid of 191 pregnant Australian women at three time points in pregnancy. Culture methods were used for detection of Ureaplasma spp. and Candida spp., and real-time PCR was used for speciation of U. parvum and U. urealyticum, non-albicans Candida spp., Mycoplasma hominis and Mycoplasma genitalium. High-resolution melt PCR was used to genotype U. parvum. Data on various lifestyle factors (including sex during pregnancy and smoking), antimicrobial use and pregnancy outcome were collected on all participants. Chi-square tests were used to assess the association of vaginal microorganisms with PTB.

RESULTS

Detection of Ureaplasma spp. was higher among spontaneous PTB cases, specifically in the presence of U. parvum [77 % preterm (95 % confidence interval (CI) 50-100 %) vs. 36 % term (CI: 29-43 %), p = 0.004], but not U. urealyticum. The association with PTB strengthened when U. parvum genotype SV6 was detected (54 % preterm (CI: 22-85 %) vs. 15 % term (CI: 10-20 %), p = 0.002); this genotype was also present in 80 % (4/5) of cases of PTB <34 weeks gestation. When present with Candida albicans in the same sample, the association with PTB remained strong for both U. parvum [46 % preterm (CI: 15-78 %) vs. 13 % term (CI: 8-18 %), p = 0.005] and U. parvum genotype SV6 [39 % preterm (CI: 8-69 %) vs. 7 % term (CI: 3-11 %), p = 0.003]. With the exception of Candida glabrata, vaginal colonisation status for all organisms was stable throughout pregnancy. Smoking significantly increased the likelihood of detection of all target organisms.

CONCLUSIONS

These data suggest that the presence of different species and serovars of Ureaplasma spp. in the vagina confers an increased risk of spontaneous PTB, findings which may be useful in risk assessment for identifying women who would benefit from antimicrobial treatment.

Prevalence and Antibiotic Susceptibility of Mycoplasma hominis and Ureaplasma urealyticum in Pregnant Women

Mycoplasma hominis (M. hominis) and Ureaplasma urealyticum (U. urealyticum) are important opportunistic pathogens that cause urogenital infections and complicate pregnancy. The aim of this study was to investigate the prevalence, effects on pregnancy outcomes, and antimicrobial susceptibilities of M. hominis and U. urealyticum. We tested vaginal swabs obtained from 1035 pregnant women for the presence of genital mycoplasmas between June 2009 and May 2014. The laboratory and clinical aspects of genital mycoplasmas infection were reviewed retrospectively, and the identification and antimicrobial susceptibility of genital mycoplasmas were determined using the Mycoplasma IST-2 kit. A total of 571 instances of M. hominis and/or U. urealyticum were detected. Of them, M. hominis was detected in two specimens, whereas U. urealyticum was detected in 472 specimens. The remaining 97 specimens were positive for both M. hominis and U. urealyticum. Preterm deliveries were frequently observed in cases of mixed infection of M. hominis and U. urealyticum, and instances of preterm premature rupture of membrane were often found in cases of U. urealyticum. The rates of non-susceptible isolates to erythromycin, empirical agents for pregnant women, showed increasing trends. In conclusion, the prevalence of M. hominis and/or U. urealyticum infections in pregnant women is high, and the resistance rate of antimicrobial agents tends to increase. Therefore, to maintain a safe pregnancy, it is important to identify the isolates and use appropriate empirical antibiotics immediately.

Identification of a gene in Mycoplasma hominis associated with preterm birth and microbial burden in intraamniotic infection

OBJECTIVE

Microbial invasion of the amniotic cavity is associated with spontaneous preterm labor and adverse pregnancy outcome, and Mycoplasma hominis often is present. However, the pathogenic process by which M hominis invades the amniotic cavity and gestational tissues, often resulting in chorioamnionitis and preterm birth, remains unknown. We hypothesized that strains of M hominis vary genetically with regards to their potential to invade and colonize the amniotic cavity and placenta.

STUDY DESIGN

We sequenced the entire genomes of 2 amniotic fluid isolates and a placental isolate of M hominis from pregnancies that resulted in preterm births and compared them with the previously sequenced genome of the type strain PG21. We identified genes that were specific to the amniotic fluid/placental isolates. We then determined the microbial burden and the presence of these genes in another set of subjects from whom samples of amniotic fluid had been collected and were positive for M hominis.

RESULTS

We identified 2 genes that encode surface-located membrane proteins (Lmp1 and Lmp-like) in the sequenced amniotic fluid/placental isolates that were truncated severely in PG21. We also identified, for the first time, a microbial gene of unknown function that is referred to in this study as gene of interest C that was associated significantly with bacterial burden in amniotic fluid and the risk of preterm delivery in patients with preterm labor.

CONCLUSION

A gene in M hominis was identified that is associated significantly with colonization and/or infection of the upper reproductive tract during pregnancy and with preterm birth.

Whole blood flow cytometric analysis of Ureaplasma-stimulated monocytes from pregnant women

We hypothesised that circulating monocytes of women with vaginal colonisation with Ureaplasma spp., genital microorganisms known to cause inflammation-driven preterm birth, would elicit a tolerised cytokine response to subsequent in vitro Ureaplasma parvum serovar 3 (UpSV3) stimulation. Using multi-parameter flow cytometry, we found no differences with regard to maternal colonisation status in the frequency of TNF-α-, IL-6-, IL-8- and IL-1β-expressing monocytes in response to subsequent UpSV3 stimulation (P > 0.10 for all cytokines). We conclude that vaginal Ureaplasma spp. colonisation does not specifically tolerise monocytes of pregnant women towards decreased responses to subsequent stimulation.

Chlamydia trachomatis and Genital Mycoplasmas: Pathogens with an Impact on Human Reproductive Health

The most prevalent, curable sexually important diseases are those caused by Chlamydia trachomatis (C. trachomatis) and genital mycoplasmas. An important characteristic of these infections is their ability to cause long-term sequels in upper genital tract, thus potentially affecting the reproductive health in both sexes. Pelvic inflammatory disease (PID), tubal factor infertility (TFI), and ectopic pregnancy (EP) are well documented complications of C. trachomatis infection in women. The role of genital mycoplasmas in development of PID, TFI, and EP requires further evaluation, but growing evidence supports a significant role for these in the pathogenesis of chorioamnionitis, premature membrane rupture, and preterm labor in pregnant woman. Both C. trachomatis and genital mycoplasmas can affect the quality of sperm and possibly influence the fertility of men. For the purpose of this paper, basic, epidemiologic, clinical, therapeutic, and public health issue of these infections were reviewed and discussed, focusing on their impact on human reproductive health.

Autoinfection as a cause of postpartum subdural empyema due to Mycoplasma hominis

Mycoplasma hominis is a commensal of the genitourinary tract, which is infrequently associated with urogenital infections. Extra-urogenital infections due to M. hominis are rare. Here, we report an unusual case of M. hominis subdural empyema in a woman occurring shortly after delivery. The patient presented with symptoms suggestive of bacterial meningitis. Spinal imaging revealed a subdural empyema that required neurosurgical intervention. Cultures from intraoperatively obtained biopsies identified M. hominis as the causative pathogen. The patient was treated with oral moxifloxacin for 4 weeks resulting in the resolution of the spinal lesion. The subdural empyema was presumably caused by a contaminated epidural blood patch performed with the patient's own blood during an episode of transient M. hominis bacteremia after delivery. The blood patch was indicated for the treatment of cerebrospinal fluid leakage, which had occurred after epidural anesthesia. Our findings highlight the significance of transient M. hominis bacteremia after delivery and implicate that M. hominis should be considered as a causative agent of extra-genitourinary tract infections particularly during the postpartum period or after genitourinary manipulation.

The Maternal Serological Response to Intrauterine Ureaplasma sp. Infection and Prediction of Risk of Pre-Term Birth

Pre-term birth (PTB) associated with intrauterine infection and inflammation (IUI) is the major cause of early PTB less than 32 weeks of gestation. Ureaplasma spp. are common commensals of the urogenital tract in pregnancy and are the most commonly identified microorganisms in amniotic fluid of pre-term pregnancies. While we have an understanding of the causal relationship between intra-amniotic infection, inflammation and PTB, we are still unable to explain why vaginal Ureaplasma sp. colonization is tolerated in some women but causes PTB in others. It is now known that placental tissues are frequently colonized by bacteria even in apparently healthy pregnancies delivered at term; usually this occurs in the absence of a significant local inflammatory response. It appears, therefore, that the site, nature, and magnitude of the immune response to infiltrating microorganisms are key in determining pregnancy outcome. Some evidence exists that the maternal serological response to Ureaplasma sp. colonization may be predictive of adverse pregnancy outcome, although issues such as the importance of virulence factors (serovars) and the timing, magnitude, and functional consequences of the immune response await clarification. This mini-review discusses the evidence linking the maternal immune response to risk of PTB and the potential applications of maternal serological analysis for predicting obstetric outcome.

Epidemiologic factors and urogenital infections associated with preterm birth in a midwestern U.S. population

OBJECTIVE

To correlate epidemiologic factors with urogenital infections associated with preterm birth.

METHODS

Pregnant women were sequentially included from four Wisconsin cohorts: large urban, midsize urban, small city, and rural city. Demographic, clinical, and current pregnancy data were collected. Cervical and urine specimens were analyzed by microscopy, culture, and polymerase chain reaction for potential pathogens.

RESULTS

Six hundred seventy-six women were evaluated. Fifty-four (8.0%) had preterm birth: 12.1% (19/157) large urban, 8.8% (15/170) midsize urban, 9.4% (16/171) small city, and 2.3% (4/178) rural city. Associated host factors and infections varied significantly among sites. Urogenital infection rates, especially Mycoplasma hominis and Ureaplasma parvum, were highest at the large urban site. Large urban site, minority ethnicity, multiple infections, and certain historical factors were associated with preterm birth by univariable analysis. By multivariable analysis, preterm birth was associated with prior preterm birth (adjusted odds ratio [aOR] 2.76, 95% confidence interval [CI] 1.27-6.02) and urinary tract infection (aOR 2.62, 95% CI 1.32-519), and negatively associated with provider-assessed good health (aOR 0.42, 95% CI 0.23-0.76) and group B streptococcal infection treatment (surrogate for health care use) (aOR 0.38, 95% CI 0.15-.99). Risk and protective factors were similar for women with birth at less than 35 weeks, and additionally associated with M hominis (aOR 3.6, 95% CI 1.4-9.7).

CONCLUSION

These measured differences among sites are consistent with observations that link epidemiologic factors, both environmental and genetic, with minimally pathogenic vaginal bacteria, inducing preterm birth, especially at less than 35 weeks of gestation.

Do nurses have worse pregnancy outcomes than non-nurses?

BACKGROUND

Nurses encounter multiple occupational exposures at work which may harm their reproductive health. The purpose of the study was to compare pregnancy complications and outcomes including cesarean deliveries, tocolysis, miscarriage, and preterm labor between female nurses and comparable women who were not nurses in Taiwan.

METHODS

This nationwide population-based study was performed using the National Health Insurance Research Database from 1997 to 2008. We identified 3,656 pregnancies among 2,326 nurses and 111,889 pregnancies among 74,919 non-nurses. A generalized estimating equation was used to compare risks between the two groups.

RESULTS

The rates of tocolysis (28.6 vs 22.3%), miscarriage (6.0 vs 5.3%), and preterm labor (8.1 vs 4.4%) were significantly higher among nurses than non-nurses. After adjustment for background differences, nurses had significantly higher risks for cesarean section (adjusted OR 1.12 [95% confidence interval (CI) 1.03-1.22]), tocolysis (OR 1.18 [95% CI 1.09-1.29]), and preterm labor (OR 1.46 [95% CI 1.28-1.67]) than non-nurses.

CONCLUSIONS

Nurses are at higher risk for cesarean section, tocolysis, and preterm labor than non-nurses. Occupational exposure related to these adverse pregnancy outcomes should be examined. Strategies to decrease the risks should be developed to improve reproductive health among nurses.

Treatment of genital mycoplasma in colonized pregnant women in late pregnancy is associated with a lower rate of premature labour and neonatal complications

Mycoplasma hominis and Ureaplasma spp. may colonize the human genital tract and have been associated with adverse pregnancy outcomes such as preterm labour and preterm premature rupture of membranes. However, as these bacteria can reside in the normal vaginal flora, there are controversies regarding their true role during pregnancy and so the need to treat these organisms. We therefore conducted a retrospective analysis to evaluate the treatment of genital mycoplasma in 5377 pregnant patients showing symptoms of potential obstetric complications at 25-37 weeks of gestation. Women presenting with symptoms were routinely screened by culture for the presence of these bacteria and treated with clindamycin when positive. Compared with uninfected untreated patients, women treated for genital mycoplasma demonstrated lower rates of premature labour. Indeed preterm birth rates were, respectively, 40.9% and 37.7% in women colonized with Ureaplasma spp. and M. hominis, compared with 44.1% in uncolonized women (Ureaplasma spp., p 0.024; M. hominis, p 0.001). Moreover, a reduction of neonatal complications rates was observed, with 10.9% of newborns developing respiratory diseases in case of Ureaplasma spp. colonization and 5.9% in the presence of M. hominis, compared with 12.8% in the absence of those bacteria (Ureaplasma spp., p 0.050; M. hominis, p <0.001). Microbiological screening of Ureaplasma spp. and/or M. hominis and pre-emptive antibiotic therapy of symptomatic pregnant women in late pregnancy might represent a beneficial strategy to reduce premature labour and neonatal complications.

Maternal intravenous treatment with either azithromycin or solithromycin clears Ureaplasma parvum from the amniotic fluid in an ovine model of intrauterine infection

Intrauterine infection with Ureaplasma spp. is strongly associated with preterm birth and adverse neonatal outcomes. We assessed whether combined intraamniotic (IA) and maternal intravenous (IV) treatment with one of two candidate antibiotics, azithromycin (AZ) or solithromycin (SOLI), would eradicate intrauterine Ureaplasma parvum infection in a sheep model of pregnancy. Sheep with singleton pregnancies received an IA injection of U. parvum serovar 3 at 85 days of gestational age (GA). At 120 days of GA, animals (n=5 to 8/group) received one of the following treatments: (i) maternal IV SOLI with a single IA injection of vehicle (IV SOLI only); (ii) maternal IV SOLI with a single IA injection of SOLI (IV+IA SOLI); (iii) maternal IV AZ and a single IA injection of vehicle (IV AZ only); (iv) maternal IV AZ and a single IA injection of AZ (IV+IA AZ); or (v) maternal IV and single IA injection of vehicle (control). Lambs were surgically delivered at 125 days of GA. Treatment efficacies were assessed by U. parvum culture, quantitative PCR, enzyme-linked immunosorbent assay, and histopathology. Amniotic fluid (AF) from all control animals contained culturable U. parvum. AF, lung, and chorioamnion from all AZ- or SOLI-treated animals (IV only or IV plus IA) were negative for culturable U. parvum. Relative to the results for the control, the levels of expression of interleukin 1β (IL-1β), IL-6, IL-8, and monocyte chemoattractant protein 2 (MCP-2) in fetal skin were significantly decreased in the IV SOLI-only group, the MCP-1 protein concentration in the amniotic fluid was significantly increased in the IV+IA SOLI group, and there was no significant difference in the histological inflammation scoring of lung or chorioamnion among the five groups. In the present study, treatment with either AZ or SOLI (IV only or IV+IA) effectively eradicated macrolide-sensitive U. parvum from the AF. There was no discernible difference in antibiotic therapy efficacy between IV-only and IV+IA treatment regimens relative to the results for the control.

VAGINAL MICROBIOME–PREGNANT HOST INTERACTIONS DETERMINE A SIGNIFICANT PROPORTION OF PRETERM LABOUR

Preterm birth (PTB) has a global prevalence of 11.1% accounting for almost 15 million babies born each year before 37 weeks of gestation. It is a risk factor in over 50% of all neonatal deaths, which amounts to 1.1 million deaths annually. Preterm birth, especially at early gestational ages is associated with a high risk of long-term morbidity in survivors. Despite much research effort, PTB rates continue to rise, placing immense financial and emotional burden on society. In the US, the annual societal economic cost associated with PTB is $26.2 billion with an average of $51,600 being spent per infant born preterm. Preterm labour (PTL) accounts for 70% of these births, of which 25% are preceded by preterm pre-labour rupture of membranes (PPROM).

Distribution and perinatal transmission of bacterial vaginal infections in pregnant women without vaginal symptoms

BACKGROUND

We evaluated the distribution and vertical transmission of bacterial vaginal infections in asymptomatic pregnant women.

METHODS

We performed multiplex PCR on secretions collected on cervical swabs from pregnant women at over 36 weeks of gestation and on oral secretions collected from their neonates immediately after delivery. We detected sexually transmitted infections (STIs) with the following 6 species: Trichomonas vaginalis, Mycoplasma hominis, Mycoplasma genitalium, Chlamydia trachomatis, Neisseria gonorrhoeae, and Ureaplasma urealyticum.

RESULTS

Infectious agents were detected in 64 of 455 pregnant women (14.1%) and in 11 neonates (2.4%). The rate of vertical transmission was 17.2% and all the infectious agents detected in neonates were concordant with those found in their mothers. U. urealyticum was the most frequently detected in the maternal genitalia, followed by M. hominis. Women who were in labor for a longer period of time had a higher risk of vertically transmitting STI agents to their neonates.

CONCLUSIONS

Vertical transmission of bacterial STIs from mothers to their infants is possible at delivery and influenced by the duration of labor. STIs should be diagnosed in pregnant women to prevent vertical transmission from the mother to the infant at the time of delivery.

Effects of Ureaplasma parvum lipoprotein multiple-banded antigen on pregnancy outcome in mice

Ureaplasma spp. are members of the family Mycoplasmataceae and have been considered to be associated with chorioamnionitis and preterm delivery. However, it is unclear whether Ureaplasma spp. have virulence factors related to these manifestations. The purpose of the present study was to determine whether the immunogenic protein multiple-banded antigen (MBA) from Ureaplasma parvum is a virulence factor for preterm delivery. We partially purified MBA from a type strain and clinical isolates of U. parvum, and also synthesized a diacylated lipopeptide derived from U. parvum, UPM-1. Using luciferase assays, both MBA-rich fraction MRF and UPM-1 activated the NF-κB pathway via TLR2. UPM-1 upregulated IL-1β, IL-6, IL-12p35, TNF-α, MIP2, LIX, and iNOS in mouse peritoneal macrophage. MRF or UPM-1 was injected into uteri on day 15 of gestation on pregnant C3H/HeN mice. The intrauterine MRF injection group had a significantly higher incidence of intrauterine fetal death (IUFD; 38.5%) than the control group (14.0%). Interestingly, intrauterine injection of UPM-1 caused preterm deliveries at high concentration (80.0%). In contrast, a low concentration of UPM-1 induced a significantly higher rate of fetal deaths (55.2%) than the control group (14.0%). The placentas of the UPM-1 injection group showed neutrophil infiltration and increased iNOS protein expression. Our data indicate that MBA from the clinical isolate of U. parvum is a potential virulence factor for IUFD and preterm delivery in mice and that the N-terminal diacylated lipopeptide is essential for the initiation of inflammation.

Ureaplasma urealyticum, Mycoplasma hominis and adverse pregnancy outcomes

PURPOSE OF REVIEW

Mycoplasma hominis and Ureaplasma urealyticum may colonize the human genital tract and have been associated with adverse pregnancy outcomes. Chorioamnionitis, spontaneous preterm labour and preterm premature rupture of membranes are significant contributors to neonatal morbidity and mortality. However, as these bacteria can reside in the normal vaginal flora, there are controversies regarding their true role during pregnancy and thus the need to treat these organisms.

RECENT FINDINGS

We review here the recent data on the epidemiology of mycoplasmas and their clinical role during pregnancy. The association of these organisms with preterm labour has been suggested by many observational studies, but proof of causality remains limited. PCR is an excellent alternative to culture to detect the presence of these organisms, but culture allows antibiotic susceptibility testing. Whether antimicrobial treatment of mycoplasma-colonized pregnant patients can effectively reduce the incidence of adverse pregnancy outcomes warrants further investigations.

SUMMARY

The role of Mycoplasma spp. and U. urealyticum in adverse pregnancy outcomes is increasingly accepted. However, sole presence of these microorganisms in the vaginal flora might be insufficient to cause pathological issues, but their combination with other factors such as bacterial vaginosis or cervical incompetence may be additionally needed to induce preterm birth.

Associations between vaginal bacteria and levels of vaginal defensins in pregnant women

OBJECTIVE

We evaluated vaginal defensin concentrations and levels of bacterial vaginosis-associated bacterial species in pregnant women.

STUDY DESIGN

Self-collected vaginal swabs from 2 visits during pregnancy were tested with quantitative polymerase chain reaction for 9 bacterial species. Beta defensins 2-3 and alpha defensins 1-3 were measured by enzyme-linked immunosorbent assay.

RESULTS

Our 126 participants were primarily African American (60%), had a mean gestational age at enrollment of 10 ± 3 weeks and at follow-up visit of 25 ± 6 weeks. At enrollment, the prevalence of bacterial vaginosis was 74% (94/126 women), which decreased to 60% (75/126 specimens) at follow-up visit. At enrollment, beta defensin 3 concentrations were significantly lower in women with bacterial vaginosis (2.64 ± 0.91 vs 3.25 ± 0.99 log(10) pg/mL; P = .003). Higher concentrations of Atopobium vaginae, bacterial vaginosis-associated bacteria1 and 2 were associated with significantly lower concentrations of beta defensin 3 (P < .01).

CONCLUSION

Bacterial vaginosis was associated with lower vaginal concentrations of beta defensin 3, but not beta defensin 2 or alpha defensins 1-3, in pregnant women.

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.

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.

Modified real-time PCR for detecting, differentiating, and quantifying Ureaplasma urealyticum and Ureaplasma parvum

We evaluated a previously described quantitative real-time PCR (qPCR) for quantifying and differentiating Ureaplasma parvum and U. urealyticum. Because of nonspecific reactions with Staphylococcus aureus DNA in the U. parvum PCR, we developed a modified qPCR and designed new primers. These oligonucleotides eradicated cross-reactions, indicating higher specificity. The detection limits of the qPCR were determined at 1 and 3 colony-forming units/ml for U. parvum and U. urealyticum, respectively. The quantification limits of the assay for both Ureaplasma species ranged from 2.10(6) to 2.10(1) copy numbers per PCR. A total of 300 patient samples obtained from the lower genital tract were tested with this newly designed qPCR assay and compared with culture results. Of the samples, 132 (44.0%) were culture positive, whereas 151 (50.3%) tested positive using qPCR. The U. parvum and U. urealyticum species were present in 79.5% and 12.6% of the qPCR-positive samples, respectively. Both species were found in 7.9% of those samples. Quantification of U. parvum and U. urealyticum in the samples ranged from less than 2.5 × 10(3) to 7.4 × 10(7) copies per specimen. In conclusion, the modified qPCR is a suitable method for rapid detection, differentiation, and quantification of U. parvum and U. urealyticum.

Mycoplasma, Ureaplasma, and adverse pregnancy outcomes: a fresh look

Recent work on the Molicutes that associate with genital tract tissues focuses on four species that may be of interest in potential maternal, fetal, and neonatal infection and in contributing to adverse pregnancy outcomes. Mycoplasma hominis and Ureaplasma urealyticum have historically been the subject of attention, but Mycoplasma genitalis which causes male urethritis in addition to colonizing the female genital tract and the division of Ureaplasma into two species, urealyticum and parvum, has also added new taxonomic clarity. The role of these genital tract inhabitants in infection during pregnancy and their ability to invade and infect placental and fetal tissue is discussed. In particular, the role of some of these organisms in prematurity may be mechanistically related to their ability to induce inflammatory cytokines, thereby triggering pathways leading to preterm labor. A review of this intensifying exploration of the mycoplasmas in relation to pregnancy yields several questions which will be important to examine in future research.