Bacterial vaginosis and prematurity in Indonesia: association in early and late pregnancy

Determinants of prematurity in urban Indonesia: a meta-analysis

OBJECTIVES

Indonesia is the fifth country with the highest number of preterm births worldwide. More than a third of neonatal deaths in Indonesia were attributed to preterm birth. Residential areas affected the occurrence of preterm birth due to differing socioeconomic and environmental conditions. Many studies have investigated the determinants of prematurity in Indonesia, however, most of them were performed in rural areas. This study is the first meta-analysis describing the determinants of preterm birth in urban Indonesia, which aimed to become the foundation upon implementing the most suitable preventative measure and policy to reduce the rate of preterm birth.

METHODS

We collected all published papers investigating the determinants of preterm birth in urban Indonesia from PubMed MEDLINE and EMBASE, using keywords developed from the following key concepts: "preterm birth", "determinants", "risk factors", "Indonesia" and the risk factors, such as "high-risk pregnancy", "anemia", "pre-eclampsia", and "infections". Exclusion criteria were multicenter studies that did not perform a specific analysis on the Indonesian population or did not separate urban and rural populations in their analysis, and articles not available in English or Indonesian. The Newcastle Ottawa Scale was used to assess the risk of bias. This systematic review was registered in PROSPERO.

RESULTS

Sixteen articles were included in the analysis and classified into five categories: genetic factors, nutrition, smoking, pregnancy characteristics or complications, and disease-related characteristics.

CONCLUSIONS

Our meta-analysis revealed adolescent pregnancy, smoking, eclampsia, bacterial vaginosis, LC-PUFA, placental vitamin D, and several minerals as the significant determinants of preterm birth in urban Indonesia.

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.

Historical Perspectives: Low Birthweight and Preterm Infants in Indonesia

The incidence of infants with low birthweight (LBW), prematurity, and small for gestational age (SGA) in Indonesia remains high, and the morbidity and mortality in these infants are significant. To study these groups of infants in Indonesia, the author searched PubMed/Medline, the Cochrane Library, Google, Indonesian reports, local publications, and doctoral and master theses in English and Indonesian from 1987 to February 2019. In this review, the development of local reference growth charts of infants born in Indonesia is described, as well as the importance of these curves in defining the prevalence of SGA infants. Some of the risk factors associated with LBW, preterm, and SGA Indonesian infants are described. The author also discusses the effectiveness of specific interventions, such as kangaroo mother care, early initiation of enteral feedings, increased breastfeeding rates, and identifying the optimal timing of hospital discharge. Some of the morbidities associated with LBW infants born in Indonesia are described. Advances in hospital care and postdischarge follow-up of LBW, preterm, and SGA infants born in Indonesia are critical to decrease the morbidity and mortality rates associated with these populations.

Bacterial Vaginosis in Pregnant Women at Maternal and Child Hospital, West Java, Indonesia, 2018: High Prevalence in Asymptomatic Females

Bacterial vaginosis (BV) is a lower genital tract infection of reproductive women which can occur in pregnant and non-pregnant women. BV in pregnant women can increase the risk of complications, including increased incidence of abortion, premature rupture of membranes, preterm birth, and babies with low birth weight. BV can also increase the risk of acquired sexually transmitted infection (STI) and their further transmission, including human immuno-deficiency virus (HIV). Each country has a different prevalence of BV. The previous report of BV prevalence in pregnant women was submitted in Jakarta, Indonesia in 1990. Until now, there is no update data of BV in pregnant women, especially in West Java, Indonesia. Thus, we conducted a descriptive observational study using a cross-sectional design and a consecutive sampling method in June 2018. This study included 60 pregnant women in the Maternal and Child Hospital, Bandung, Indonesia. Out of 60 participants, seven (11.67%) participants had BV according to Amsel criteria. Asymptomatic BV was diagnosed in all participants. This study shows the prevalence of BV in pregnant women in the Maternal and Child Hospital in Bandung during June 2018. The assessment of screening BV should be recommended as a routine workup. To avoid complications in pregnant women and infants it should not be waited for the symptoms to reveal.

Bacterial vaginosis, vulvovaginal candidiasis and trichomonal vaginitis among reproductive-aged women seeking primary healthcare in Sana'a city, Yemen

BACKGROUND

In Yemen, the underlying causes of infectious vaginitis have been neglected. Therefore, this study aimed to determine the prevalence and risk factors associated with bacterial vaginosis (BV), vulvovaginal candidiasis (VVC) and trichomonal vaginitis (TV) among non-pregnant reproductive-aged women.

METHODS

A cross-sectional study was conducted among 347 non-pregnant reproductive-aged women seeking primary healthcare in Sana'a city, Yemen. Data about sociodemographic characteristics, lifestyle-related behaviors, routine hygienic practices, menstrual care and history and type of contraceptive intake were collected using a structured questionnaire. Vaginal discharge samples were collected and examined for discharge characteristics and pH by a gynecologist. Then, samples were examined for BV, VVC and TV. Data were analyzed using suitable statistical tests.

RESULTS

Vaginal infections were prevalent among 37.6% of reproductive-aged women, where BV was the most prevalent (27.2%). VVC was significantly higher among symptomatic women and significantly associated with itching (P = 0.005). Using bivariate analysis, the age of < 25 years (odds ratio [OR] = 1.9, 95% confidence interval [CI]: 1.16-3.10; P = 0.010) and using intrauterine contraceptive devices (IUCDs) (OR = 1.8, 95% CI: 1.09-2.89; P = 0.020) were significantly associated with BV, while history of miscarriage was significantly associated with a lower risk of BV (OR = 0.5, 95% CI: 0.31-0.85, P = 0.009). However, polygyny was significantly associated with VVC (OR = 3.4, 95% CI: 1.33-8.66; P = 0.007). Multivariable analysis confirmed that age of < 25 years and using IUCD were the independent predictors of BV, while history of miscarriage was an independent protective factor against BV. On the other hand, marriage to a polygamous husband was the independent predictor of VVC.

CONCLUSIONS

More than a third of non-pregnant reproductive-aged women seeking PHC in Sana'a have single or mixed infections with BV, VVC or TV. BV is the most frequent cause of vaginitis and is significantly associated with the age of < 25 years and using IUCDs, while VVC is significantly higher among women with polygamous husbands. Health education of polygamous husbands and their wives, regular monitoring of BV among IUCD users and screening women for vaginitis before treatment are recommended.

Vaginal microbiome in early pregnancy and subsequent risk of spontaneous preterm birth: a case-control study

OBJECTIVES

To explore differences in the vaginal microbiome between preterm and term deliveries.

DESIGN

Nested case-control study in 3D cohort (design, develop, discover).

SETTING

Quebec, Canada.

SAMPLE

Ninety-four women with spontaneous preterm birth as cases [17 early (<34 weeks) and 77 late (34-36 weeks) preterm birth] and 356 women as controls with term delivery (≥37 weeks).

METHODS

To assess the vaginal microbiome by sequencing the V4 region of the 16S ribosomal RNA (rRNA) gene in swabs self-collected during early pregnancy.

MAIN OUTCOME MEASURES

Comparison of relative abundance of bacterial operational taxonomic units and oligotypes and identifying vaginal community state types (CSTs) in early or late spontaneous preterm and term deliveries.

RESULTS

Lactobacillus gasseri/ Lactobacillus johnsonii (coefficient -5.36, 95% CI -8.07 to -2.65), Lactobacillus crispatus (99%)/ Lactobacillus acidophilus (99%) (-4.58, 95% CI -6.20 to -2.96), Lactobacillus iners (99%)/ Ralstonia solanacearum (99%) (-3.98, 95% CI -6.48 to -1.47) and Bifidobacterium longum/ Bifidobacterium breve (-8.84, 95% CI -12.96 to -4.73) were associated with decreased risk of early but not late preterm birth. Six vaginal CSTs were identified: four dominated by Lactobacillus; one with presence of bacterial vaginosis-associated bacteria (Gardnerella vaginalis, Atopobium vaginae and Veillonellaceae bacterium) (CST IV); and one with nondominance of Lactobacillus (CST VI). CST IV was associated with increased risk of early (4.22, 95% CI 1.24-24.85) but not late (1.63, 95% CI 0.68-5.04) preterm birth, compared with CST VI.

CONCLUSIONS

Lactobacillus gasseri/L. johnsonii, L. crispatus/L. acidophilus, L. iners/R. solanacearum and B. longum/B. breve may be associated with decreased risk of early preterm birth. A bacterial vaginosis-related vaginal CST versus a CST nondominated by Lactobacillus may be associated with increased risk of early preterm birth.

TWEETABLE ABSTRACT

Largest study of its kind finds certain species of vaginal Lactobacillus + Bifidobacterium may relate to lower risk of preterm birth.

Malarial Infection and Curable Sexually Transmitted and Reproductive Tract Infections Among Pregnant Women in a Rural District of Zambia

Malarial infection and curable sexually transmitted and reproductive tract infections (STIs/RTIs) are important causes of adverse birth outcomes. Reducing the burden of these infections in pregnancy requires interventions that can be easily integrated into the antenatal care (ANC) package. However, efforts to integrate the control of malarial infection and curable STIs/RTIs in pregnancy have been hampered by a lack of evidence related to their coinfection. Thus, we investigated the prevalence of coinfection among pregnant women of rural Zambia. A prospective cohort study was conducted in Nchelenge District, Zambia, involving 1,086 first ANC attendees. We screened participants for peripheral malarial infection and curable STIs/RTIs (syphilis, Chlamydia, gonorrhea, trichomoniasis, and bacterial vaginosis), and collected relevant sociodemographic data at booking. Factors associated with malarial and STI/RTI coinfection were explored using univariate and multivariate regression models. Among participants with complete results (N = 1,071), 38.7% (95% confidence interval [CI] = 35.7-41.6) were coinfected with malaria parasites and at least one STI/RTI; 18.9% (95% CI = 16.5-21.2) were infected with malaria parasites only; 26.0% (95% CI = 23.5-28.8) were infected with at least one STI/RTI but no malaria parasites, and 16.4% (95% CI = 14.1-18.6) had no infection. Human immunodeficiency virus (HIV)-infected women had a higher risk of being coinfected than HIV-uninfected women (odds ratio [OR] = 3.59 [95% CI = 1.73-7.48], P < 0.001). The prevalence of malarial and STI/RTI coinfection was high in this population. An integrated approach to control malarial infection and STIs/RTIs is needed to reduce this dual burden in pregnancy.

Bacterial Vaginosis and Pregnancy Outcome in Lagos, Nigeria

Background.  Bacterial vaginosis (BV) is a complex clinical syndrome characterized by alterations in the normal vaginal flora and a malodorous discharge when symptomatic. In pregnancy, BV has been associated with adverse outcomes such as miscarriage, premature rupture of membranes, preterm birth, and low birth weight. This study was conducted to determine the prevalence and associations of BV and pregnancy outcomes among pregnant women in Lagos University Teaching Hospital (LUTH). Methods.  We conducted a prospective observational study with high vaginal swabs obtained from consecutive newly registered antenatal women between 14 and 36 weeks gestation. The women were monitored until delivery, and their pregnancy outcome and demographic data were obtained using an interviewer-administered questionnaire. Results.  Bacterial vaginosis was diagnosed by Nugent score in 64 of 246 women, giving a prevalence rate of 26%. Bacterial vaginosis was significantly associated with preterm delivery (risk ratio [RR], 2.68; 95% confidence interval [CI], 1.44-4.98), low birth weight (RR, 3.20; 95% CI, 1.29-7.94), and premature rupture of membranes (RR, 6.75; 95% CI, 3.11-14.67). The association between BV and miscarriage (<28 weeks gestation) and neonatal admission for various morbidities was not statistically significant. Conclusions.  The prevalence rate of BV among pregnant women in LUTH is high and is significantly associated with adverse pregnancy outcome. Routine screening and treatment of women preconceptually may enable interventions to prevent these adverse outcomes.

Advances in the Prevention of Infection-Related Preterm Birth

Infection-related preterm birth (PTB) is more common at early gestational ages and is associated with major neonatal mortality and morbidity. Abnormal genital tract microflora in early pregnancy predicts late miscarriage and early PTB. Accordingly, it is logical to consider antibiotics as an intervention. Unfortunately, the conclusions of systematic reviews and meta-analyses (SR&MAs) carried out in an attempt to explain the confusion over the heterogeneity of individual studies are flawed by the fact that undue reliance was placed on studies which: (a) had a suboptimal choice of antibiotic (mainly metronidazole) or used antibiotics not recommended for the treatment of bacterial vaginosis (BV) or BV-related organisms; (b) used antibiotics too late in pregnancy to influence outcome (23–27 weeks); and (c) included women whose risk of PTB was not due to abnormal genital tract colonization and hence unlikely to respond to antibiotics. These risks included: (a) previous PTB of indeterminate etiology; (b) low weight/body mass index; or (c) detection of fetal fibronectin, ureaplasmas, Group B streptococcus or Trichomonas vaginalis). While individual studies have found benefit of antibiotic intervention for the prevention of PTB, in meta-analyses these effects have been negated by large methodologically flawed studies with negative results. As a result, many clinicians think that any antibiotic given at any time in pregnancy to any woman at risk of PTB will cause more harm than good. Recently, a more focused SR&MA has demonstrated that antibiotics active against BV-related organisms, used in women whose risk of PTB is due to abnormal microflora, and used early in pregnancy before irreversible inflammatory damage has occurred, can reduce the rate of PTB. This review presents those data, the background and attempts to explain the confusion using new information from culture-independent molecular-based techniques. It also gives guidance on the structure of putative future antibiotic intervention studies.

Antimicrobial and immune modulatory effects of lactic acid and short chain fatty acids produced by vaginal microbiota associated with eubiosis and bacterial vaginosis

Lactic acid and short chain fatty acids (SCFAs) produced by vaginal microbiota have reported antimicrobial and immune modulatory activities indicating their potential as biomarkers of disease and/or disease susceptibility. In asymptomatic women of reproductive-age the vaginal microbiota is comprised of lactic acid-producing bacteria that are primarily responsible for the production of lactic acid present at ~110 mM and acidifying the vaginal milieu to pH ~3.5. In contrast, bacterial vaginosis (BV), a dysbiosis of the vaginal microbiota, is characterized by decreased lactic acid-producing microbiota and increased diverse anaerobic bacteria accompanied by an elevated pH>4.5. BV is also characterized by a dramatic loss of lactic acid and greater concentrations of mixed SCFAs including acetate, propionate, butyrate, and succinate. Notably women with lactic acid-producing microbiota have more favorable reproductive and sexual health outcomes compared to women with BV. Regarding the latter, BV is associated with increased susceptibility to sexually transmitted infections (STIs) including HIV. In vitro studies demonstrate that lactic acid produced by vaginal microbiota has microbicidal and virucidal activities that may protect against STIs and endogenous opportunistic bacteria as well as immune modulatory properties that require further characterization with regard to their effects on the vaginal mucosa. In contrast, BV-associated SCFAs have far less antimicrobial activity with the potential to contribute to a pro-inflammatory vaginal environment. Here we review the composition of lactic acid and SCFAs in respective states of eubiosis (non-BV) or dysbiosis (BV), their effects on susceptibility to bacterial/viral STIs and whether they have inherent microbicidal/virucidal and immune modulatory properties. We also explore their potential as biomarkers for the presence and/or increased susceptibility to STIs.

The vaginal microbiota and susceptibility to HIV

There is some evidence that the risk of HIV infection per heterosexual act is higher in low-income countries than in high-income countries. We hypothesize that variations in per sex-act transmission probability of HIV may in part be attributed to differences in the composition and function of the vaginal microbiota between different populations. This paper presents data that are in support of this hypothesis. Experimental and clinical studies have provided evidence that the normal vaginal microbiota plays a protective role against acquisition of HIV and other sexually transmitted infections. Epidemiological studies have convincingly shown that disturbances of the vaginal microbiome, namely intermediate flora and bacterial vaginosis, increase the risk of acquisition of HIV infection. A review of the literature found large differences in prevalence of bacterial vaginosis between different populations, with the highest prevalence rates found in black populations. Possible explanations for these differences are presented including data suggesting that there are ethnic differences in the composition of the normal vaginal microbiota. Lastly, interventions are discussed to restore and maintain a healthy vaginal environment.

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

BACKGROUND

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

RESULTS

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

CONCLUSION

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

Attitudes towards microbicide use for bacterial vaginosis in pregnancy

Background Bacterial vaginosis (BV) is the most common reproductive tract infection (RTI) and is a significant risk factor for preterm birth. Microbicides could be an option for the prevention and treatment of BV in pregnancy, and understanding use of the product will be crucial. The present study explored attitudes of women in the third trimester of pregnancy regarding topical microbicide use for the prevention and treatment of BV.

METHODS

Twenty-six women in their third trimester were interviewed regarding their knowledge and beliefs about RTIs during pregnancy and attitudes concerning the use of topical microbicides for prevention and treatment of BV.

RESULTS

Participants had a mean age of 24.9 years, were largely under-represented minorities and the majority had had past pregnancies. Participants had knowledge and experience with RTIs but not BV. They were open to the use of microbicides for prevention or treatment of BV, but believed that women requiring treatment would be more motivated. Rationales for acceptability were most commonly related to the baby's health. Practical issues that may interfere with use were often, but not always, related to pregnancy. There was a range of attitudes about partner involvement in decision-making and the practicalities of product use.

CONCLUSION

Pregnant women are knowledgeable about RTIs but not necessarily BV. The women in this study found microbicide use acceptable, particularly for treatment. To improve acceptability and use, education would be needed about BV and possible complications, how to overcome practical problems and the value of involving partners in the decision.

The global epidemiology of bacterial vaginosis: a systematic review

Bacterial vaginosis (BV) enhances the acquisition and transmission of a range of sexually transmitted infections including human immunodeficiency virus. This has made it more important to uncover the reasons why some populations have very high BV prevalences and others not. This systematic review describes the global epidemiology of BV. It summarizes data from peer-reviewed publications detailing the population prevalence of BV as diagnosed by a standardized and reproducible methodology-Nugent scoring system. BV variations between countries, and between ethnic groups within countries, are described. We evaluated 1692 English- and non-English-language articles describing the prevalence of BV using MEDLINE and the Web of Science databases. A total of 86 articles met our inclusion criteria. BV prevalences were found to vary considerably between ethnic groups in North America, South America, Europe, the Middle East, and Asia. Although BV prevalence is, in general, highest in parts of Africa and lowest in much of Asia and Europe, some populations in Africa have very low BV prevalences and some in Asia and Europe have high rates.

Rescreening for abnormal vaginal flora in pregnancy and re-treating with clindamycin vaginal cream significantly increases cure and improvement rates

We investigated 199 pregnant women with bacterial vaginosis (BV) who received clindamycin vaginal cream (CVC) for three days and compared with 205 women treated with placebo. The vaginal flora was assessed at each visit. At the second visit, 71% in the CVC group were cured/improved, compared with 12% in the placebo group (P < 0.001). At visit 3 about 90% who responded to initial CVC treatment were still cured/improved. Of women who initially failed to respond to CVC and were given an additional seven-day course, 33% were cured/improved by the third visit, compared with 15% who failed to respond to placebo initially and were given a further seven-day course (P = 0.02). By visit 4, half the women in the CVC group who received additional treatment remained cured/improved, compared with 26% who had additional placebo (P = 0.004). In the CVC group, a change from abnormal to normal rose from 71% (visit 2) to 76% (visit 3) and 79% (visit 4). A similar trend was seen in women who received placebo but the proportions were significantly lower (12%, 24% and 33%, respectively). There is value in rescreening and re-treating women who remain BV-positive after initial clindamycin treatment.

Evaluation of specific symptoms of bacterial vaginosis among pregnant women

Objective: Identification of the symptoms of bacterial vaginosis (BV) in pregnancy might be rational in order to identify a possible BV-associated group at risk of preterm delivery.

Methods: Three hundred and five women early in the third trimester of pregnancy were interviewed about lifestyle factors and specific symptoms of BV and given a vaginal examination. A longitudinal three-week follow-up was conducted for 127 women.

Results: The prevalence of BV was 16%. Women with BV were significantly more often smokers than women without BV (52% vs. 34%). No difference in sexual activity or other behavioral characteristics between the two groups were seen. No differences were noted among women with and without BV according to specific symptoms: malodorous discharge (26% vs. 23%), increased discharge (76% vs. 68%), or itching or troublesome discharge. More than one third of women with BV at the first examination did not fulfill the criteria for BV at the three week follow-up exam. None of the women without BV had developed BV by the follow-up exam. The incidence of preterm delivery among women with BV was 4%, women without BV had an incidence of 2.4%. This difference was not statistically significant.

Conclusion: Asymptomatic BV in pregnancy is common. Specific questions about the character of the discharge do not identify women with BV during pregnancy. To identify a potential BV-associated group at risk for preterm delivery, screening for BV must be conducted not only among symptomatic women but among all women. Women with BV are more often smokers than women without BV.

Diagnosis of vaginal discharge by wet mount microscopy: a simple and underrated method

Vaginal discharge is highly variable in quality and quantity among different individuals, and even in the same individual during different periods of life. Vaginal discharge is most commonly caused by infection with sexually transmitted organisms or increased colonization by different facultative pathogenic microorganisms (i.e., Gardnerella vaginalis). Noninfectious causes of vaginal discharge are quite rare (10% noninfectious as compared to 90% infectious causes). Most common in women with a vaginal infection is bacterial vaginosis (40%-50% of cases), followed by vulvovaginal candidosis (20%-25%), and then trichomoniasis (15%-20%). If infection is suspected as the primary cause, a sample of the vaginal discharge should be taken and examined microscopically. When evaluating vaginal secretions by phase-contrast wet mount microscopy, knowledge of what is normal versus abnormal is very important. Knowledge of the sensitivity and specificity of wet mount microscopy in different clinical settings is also important.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians

LEARNING OBJECTIVES

After completing this CME activity, physicians should be better able to evaluate lifetime changes in vaginal secretions, characterize the physiological and pathological appearance of vaginal discharge, assess the clinical practicality and usefulness of wet mount microscopy and use wet mount microscopy to diagnose bacterial vaginosis and other common vaginal infections.

Demographic, clinical and microbiological characteristics of maternity patients: a Canadian clinical cohort study

OBJECTIVE

To determine the demographic, clinical and microbiological characteristics of a representative Canadian obstetrical population.

DESIGN

A one-year cohort study of all maternity patients who were followed to delivery, using detailed patient questionnaires containing more than 60 demographic and clinical variables, and three microbiological evaluations during gestation - first trimester, 26 to 30 weeks, and labour and delivery. Outcome measurements included birth weight and gestational age.

SETTING

Labour and delivery suites of all office obstetrical practices affiliated with a single hospital.

POPULATION STUDIED

A consecutive sample of pregnant women in the study practices during one year were eligible for enrolment; 2237 consecutive patients were approached for consent, 2047 enrolled and 1811 completed the study through delivery.

RESULTS

The average patient was white, married and 29 years of age. Slightly more than half of the patients had postsecondary education, but 10% fell below the national poverty line for income. Frequency of factors linked to adverse pregnancy outcomes included cigarette smoking (19%), alcohol ingestion (18%), previously having had a premature infant (7%), and maternal diabetes (2%). Overall prevalence of genital microbes variously implicated in prematurity was 37% for ureaplasma, 11% for group B streptococcus and 4% for Mycoplasma hominis. Prevalence of bacterial vaginosis was 14%. The median gestational age for the cohort was 39 weeks, with 7% of infants born less than 37 weeks' gestation. Mean birth weight was 3415 g.

CONCLUSIONS

The present clinical cohort represents demographic and medical characteristics of the Canadian obstetrical population. The birth outcomes are consistent with national data. This database provides valuable information about a general obstetrical population that is managed by a universal health care system.

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.

Estimation of the Incidence of Bacterial Vaginosis and other Vaginal Infections and its Consequences on Maternal/Fetal Outcome in Pregnant Women Attending an Antenatal Clinic in a Tertiary Care Hospital in North India

Aims:

This study was undertaken to estimate the incidence of bacterial vaginosis (BV) and other vaginal infections during pregnancy and its association with urinary tract infections (UTI) and its consequences on pregnancy outcome, maternal and fetal morbidity and mortality.

Settings and Design:

Prospective cohort study.

Materials and Methods:

The present prospective cohort study was conducted on 200 women attending the antenatal clinic (ANC) of a tertiary hospital. All pertinent obstetric and neonatal data covering antenatal events during the course of pregnancy, delivery, puerperium and condition of each newborn at the time of birth were collected. BV was detected by both Gram stain and gold standard clinical criteria (Amsel’s composite criteria).

Statistical analysis used:

Data were analyzed using SPSS version 9. Fischer’s exact test, chi square tests and Student’s’ test has been used for analysis. The probability of 5% was considered as significant for continuous variables such as age, period of gestation and birth weight. Odds ratio (OR) and confidence interval (CI) with 95% probability were determined.

Results:

The incidence of bacterial vaginosis was 41 in 200 patients. Adverse outcomes such as preterm labor, PROM and fetal complications were found more in pregnant women who had bacterial vaginosis (N=41), bacterial vaginosis with UTI (N=14) as compared to those without bacterial vaginosis (N=118).

Conclusions:

The incidence of poor pregnancy outcome was higher in bacterial vaginosis with UTI. Prevention of BV and UTI is cost effective to minimize the pregnancy-related complications and preterm labor to decrease in perinatal and maternal mortality and morbidity. We recommend all antenatal patients should be screened for the presence of bacterial vaginosis, other infections and UTI.

Periodontal disease and bacterial vaginosis as genetic and environmental markers for the risk of spontaneous preterm labor and preterm birth

OBJECTIVE

The aim of this study was to review the evidence associating periodontal disease, and bacterial vaginosis with preterm birth, and the link with gene polymorphism, as well as the preventions and interventions which might reduce the risk of spontaneous preterm labor and preterm births in women with periodontal disease and/or bacterial vaginosis.

BACKGROUND

Preterm birth accounts for 70% of perinatal mortality, nearly 50% of long term neurological morbidity, and a significant impact on health care costs. There is evidence that spontaneous preterm labor and preterm birth are associated with intrauterine infection due to abnormal genital and/or oral colonization. Periodontal disease and bacterial vaginosis share microbiological similarities, and both conditions are associated with spontaneous preterm labor and preterm birth. In addition, periodontal disease and bacterial vaginosis have been linked through gene polymorphism.

METHODS

A review of the literature using widely accepted scientific search engines in English language.

RESULTS

Studies evaluating antibiotic administration to eradicate periodontal disease and/or bacterial vaginosis responsible organisms, and minimize the risk of preterm births have yielded conflicting results. With respect to bacterial vaginosis, the timing and the choice of antibiotic administration might partly explain the conflicting results. The use of scaling and/or root planning for women with periodontal disease appears to reduce the risk of preterm birth, but routine administration of antibiotics has not demonstrated any impact on preterm birth.

CONCLUSION

Prospective studies evaluating the association of gene polymorphism with preterm birth, and the contribution of periodontal disease and bacterial vaginosis are needed.

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

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

Does midtrimester Nugent score or high vaginal pH predict gestational age at delivery in women at risk for recurrent preterm birth?

OBJECTIVE

To estimate whether bacterial vaginosis, as defined by either Nugent score or vaginal pH, predicts gestational age at delivery in women at risk for recurrent preterm birth.

STUDY DESIGN

Planned secondary analysis of a randomized cerclage trial in women with prior spontaneous preterm birth 17⁰(/)⁷-33⁶(/)⁷ weeks. Vaginal Gram stain and pH were collected at the initial study visit. Women not assigned to cerclage, either because they did not experience cervical shortening <25 mm or because they were randomly assigned to no cerclage, were studied.

RESULTS

Seven hundred eighty-six women had complete delivery gestational age, Gram stain, and pH results. The diagnosis of bacterial vaginosis by either Nugent score ≥ 7 or by pH ≥ 5 was not associated with earlier birth.

CONCLUSION

The presence of bacterial vaginosis at 16-21⁶(/)⁷ weeks does not predict gestational age at birth in women at risk for recurrent preterm birth.

Pharmacokinetics of metronidazole in pregnant patients with bacterial vaginosis

OBJECTIVE

The present study was undertaken to investigate the pharmacokinetics of metronidazole in pregnant patients with bacterial vaginosis.

METHODS

Twenty patients received metronidazole (Flagyl ®, Pfizer, 235 East 42nd Street, NY, NY 10017) oral dose 500 mg twice a day for 3 consecutive days. Pharmacokinetic analyses of metronidazole were performed after a single oral dose on the morning of day 4.

RESULTS

Although absolute estimates of metronidazole total body exposure were highest in women during early term pregnancy, weight-corrected estimates of exposure maximum plasma drug concentration (C(max)) and the area under the plasma concentration-versus-time curve (AUC(0-12)), along with apparent oral clearance and distribution volume, were not significantly different between women at early, middle, and late stages of pregnancy and were in the range of reported values for nonpregnant patients receiving a similar dose.

CONCLUSIONS

The pharmacokinetic profile of metronidazole did not change at the different time points assessed during pregnancy.

Pregnancy complications associated with bacterial vaginosis and their estimated costs

Objective: This study was undertaken to estimate the annual direct costs of complications associated with bacterial vaginosis (BV) in pregnant women in the United States.

Methods: An economic model was developed from evidence in the published literature linking perinatal complications to BV. The estimates of attributable risks were applied to the estimated population of pregnant women in the United States in 1993. The charge data from a database of hospital utilization information were then used to estimate the direct costs of each pregnancy complication and the total direct costs associated with BV.

Results: Under the assumptions of our model, the direct costs of preterm labor, preterm delivery, the attendant low birth weight (LBW), and other perinatal complications associated with BV were estimated at nearly $1.0 billion in 1993. Over 40% of the total cost was associated with preterm delivery and intensive care of LBW infants, while another 24.5% of the cost was related to preterm labor.

Conclusions: If the current frequency of BV among pregnant women persists and BV is not detected and treated during pregnancy, the projected annual costs will reach $1.4 billion by the year 2000. Reducing the heavy economic burden associated with BV in pregnant women will require the establishment of effective screening and treatment regimens.

Correlation between the clinical diagnosis of bacterial vaginosis and the results of a proline aminopeptidase assay

Objective: The object of this study was to develop a simple and inexpensive test for detection of bacterial vaginosis (BV) in pregnant patients and to test its accuracy in a clinic population.

Methods: We developed a modified proline aminopeptidase (PAMP) assay to detect BV and compared the results of the assay with the clinical diagnosis of BV.

Results: The results of the PAMP assay in 55 asymptomatic and 50 symptomatic subjects significantly correlated with a clinical diagnosis of BV. The prevalence of BV in the asymptomatic population was 42% (PAMP assay) and 38% (clinical diagnosis). In the symptomatic population, it was 50% (PAMP assay) and 54% (clinical diagnosis). The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the PAMP assay were 86, 85, 86, 78, and 91%, respectively, in asymptomatic patients and 89, 96, 92, 96, and 88%, respectively, in symptomatic patients.

Conclusions: The modified PAMP assay, which we describe, met our goals for simplicity, cost, and accuracy. We feel it could be best used as a screening test for BV in asymptomatic pregnant patients.

Bacterial vaginosis diagnosed at the first antenatal visit better predicts preterm labour than diagnosis later in pregnancy

This study was conducted as part of a double-blind randomised placebo-controlled trial, the aim of which was to determine whether vitamin C could reduce the recurrence risk of pre-term labour. In this study, women with a history of pre-term labour in a preceding pregnancy were randomised to receive either 250 mg vitamin C or a matching placebo twice daily until 34 weeks' gestation. They attended a dedicated pre-term labour clinic every 2 weeks. All women were screened for bacterial vaginosis (BV) at each visit. It was first determined that vitamin C did not have any effect on the presence of BV. Women who were diagnosed with BV before 20 weeks' gestation were at higher risk of delivering pre-term than those who developed BV after 20 weeks.

Fetal fibronectin as a predictor of preterm birth

Preterm delivery remains the leading cause of perinatal mortality and occurs in approximately 7-9% of pregnancies. The main problem for the obstetrician is the inability to detect women at risk from this complication. The presence of fetal fibronectin (fFN) in cervicovaginal secretions has been proposed as a specific predictor of preterm delivery. Immunohistochemical studies suggest that fFN is present in the extracellular matrix of the decidua basalis next to the intervillus space. It has been studied intensively in symptomatic patients and has a positive predictive value of 43-79%. It has also a negative predictive value of 99.7% for birth within 7 days and 93% for delivery before 37 weeks. Similarly, in high-risk asymptomatic women, it has been proved a useful screening tool for the prediction of preterm delivery, yielding a sensitivity of 43-92%, a specificity of 52-93%, a positive predictive value of 43-85% and a negative predictive value of 86-99%. In low-risk asymptomatic women, fFN has a sensitivity of 63-73%, a specificity of 80-98%, a positive predictive value of 13-36% and a negative predictive value of 95-97%. In women presenting with preterm contractions, a negative test may make one withhold potentially dangerous tocolytic therapy. In asymptomatic women this test can identify patients who have a very high risk for early delivery. Women identified as being high-risk can be offered steroid injections in order to improve lung maturity in preterm babies. Additionally, they can be counselled about the signs and symptoms of preterm labour, so that they can seek medical advice before labour is actually established. However, extensive research is still needed, as no clear benefit in preventing preterm birth using this test, has been shown so far.

Acquisition and elimination of bacterial vaginosis during pregnancy: a Danish population-based study

Objectives: the aim was to examine factors associated with acquisition and elimination of bacterial vaginosis in pregnancy. Methods: a group of 229 pregnant women were randomly selected from a population-based prospective cohort study of 2927. They were examined at enrollment (mean gestational weeks 16w + 0d) and again in mid-third trimester (mean gestational age 32w + 3d). Measures: BV (Amsel's clinical criteria), microbiological cultures of the genital tract and questionnaire data. Results: BV prevalence decreased from 17% in early second trimester to 14% in mid-third trimester due to a tenfold higher elimination rate (39%) than incidence rate (4%). Heavy smokers (> 10/d) in early pregnancy were at increased risk (5.3 [1.1–25]) for the acquisition of BV during pregnancy, as were women receiving public benefits (4.8 [1.0–22]), having a vaginal pH above 4.5 (6.3 [1.4–29]) or vaginal anaerobe bacteria (18 [2.7–122]) at enrollment. A previous use of combined oral contraceptives was preventive for the acquisition of BV (0.2 [0.03–0.96]). Elimination of BV in pregnancy tended to be associated with a heavy growth of Lactobacillus (3.2 [0.8–13]) at enrollment. Conclusions: acquisition of BV during pregnancy is rare and is associated with smoking, while the presence of anaerobe bacteria and a vaginal pH > 4.5 are interpreted as steps on a gradual change towards BV. In the same way heavy growth of Lactobacillus spp in early pregnancy may be an indicator of women on the way to eliminate BV.

The relationship between periodontal disease, bacterial vaginosis, and preterm birth

Spontaneous preterm labor leading to preterm birth is a major cause of perinatal mortality and morbidity worldwide. The etiology of spontaneous preterm labor is multifactoral but there is overwhelming evidence to implicate infection in up to 40% of cases. Historically, this infective link has focused on the associations between abnormal genital tract flora in pregnancy (diagnosed by the presence of bacterial vaginosis) and preterm birth. Recently, another condition related to abnormal flora (periodontal disease) has been linked with preterm birth. There are microbiological similarities between the oral cavity and the female genital tract giving rise to a possible common pathophysiology. This review records the interrelationship between periodontal disease, bacterial vaginosis, and preterm birth. We postulate on the mechanism linking the three conditions, particularly through microbiology and gene-environmental interactions. Periodontal disease and bacterial vaginosis may be risk factors in their own rights or may be interrelated. We speculate on whether periodontitisis a marker for an immune hyperresponse to abnormal flora which in the oral cavity results in periodontitis and in the case of bacterial vaginosis might result in preterm birth. We also postulate on the risk of preterm birth by periodontitis alone, bacterial vaginosis alone, or both.

Asymptomatic trichomonas and candida colonization and pregnancy outcome

Trichomonas vaginalis is a sexually transmitted surface pathogen of the lower urogenital tract, and may be associated with asymptomatic vaginal colonization or intensely symptomatic vaginitis. In pregnancy it is associated with an increased risk of preterm delivery. However, a randomized trial of treatment of asymptomatic trichomonas colonization in pregnancy showed an increase in the risk of preterm delivery in treated women. The reasons for this paradox are yet to be fully elucidated. Candida species, on the other hand, may be present--usually in the yeast form--in the vaginal flora of up to 40% of healthy pregnant women. Although candidiasis is not usually associated with chorioamnionitis or preterm delivery, there is some emerging evidence to suggest that screening for and eradication of candida during pregnancy may reduce the risk of preterm delivery. This chapter reviews the impact of these common vaginal infections on pregnancy outcome and appraises the recent evidence on the role of treatment during pregnancy.

Asymptomatic bacterial vaginosis and intermediate flora as risk factors for adverse pregnancy outcome

We updated a previously published meta-analysis to evaluate bacterial vaginosis (BV) and intermediate vaginal flora as risk factors for adverse pregnancy outcome. Selection criteria were original, published, English-language reports of cohort studies or control groups of clinical trials including women <37 weeks' gestation with intact amniotic membranes. All women had to be screened for BV, diagnosed either by clinical criteria or by criteria based on Gram-stain findings. Outcomes were preterm delivery, late miscarriages, maternal or neonatal infections, and perinatal mortality. Fourteen new studies with results for 10,286 patients were included, so that results for 30,518 patients in 32 studies were available for this meta-analysis. BV more than doubled the risk of preterm delivery in asymptomatic patients (OR: 2.16, 95% CI: 1.56-3.00) and in patients with symptoms of preterm labor (OR: 2.38, 95% CI: 1.02-5.58). BV also significantly increased the risk of late miscarriages (OR: 6.32, 95% CI: 3.65-10.94) and maternal infection (OR: 2.53, 95% CI 1.26-5.08) in asymptomatic patients. No significant results were calculated for the outcomes of neonatal infection or perinatal mortality. Also, intermediate vaginal flora was not significantly associated with any outcome included. The results of this meta-analysis confirm that BV is a risk factor for preterm delivery and maternal infectious morbidity and a strong risk factor for late miscarriage.

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

OBJECTIVE

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

DESIGN

Prospective cohort study.

SETTING

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

POPULATION

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

METHODS

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

MAIN OUTCOME MEASURES

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

RESULTS

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

CONCLUSIONS

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

Bacterial Vaginosis and Group B Streptococcal Colonization and Preterm Delivery in a Low-Risk Population

OBJECTIVE

To evaluate the relationship between bacterial vaginosis (BV) and group B streptococcal (GBS) colonization in the 2nd trimester of pregnancy and preterm delivery.

METHODS

1,197 pregnant women between 22 and 25 weeks' gestation had a high vaginal swab for assessment of BV and GBS. Exclusion criteria were: previous preterm delivery, or mid-trimester abortion or termination of pregnancy, multiple gestation, oligo- or polyhydramnios, placenta previa, fetal abnormalities, uterine malformations, cervical incompetence, cervical cerclage, or receipt of an antibiotic effective against BV or GBS following the screening. All women had no risk factors for preterm delivery. The primary outcome measure in this analysis was spontaneous preterm delivery before 37 weeks' gestation.

RESULTS

The preterm delivery rate was 8.7%, while the maternal BV and GBS colonization rates were 7.9 and 12.5%, respectively. Following adjustment for potential confounders BV was associated with an increased risk of preterm delivery (RR 2.19; CI: 1.21-3.98) (p = 0.01). On the contrary, GBS colonization was found to have a negative correlation with preterm birth (RR 0.43; 95% CI: 0.19-1.00).

CONCLUSIONS

Although BV is a risk factor for preterm delivery, GBS colonization in the 2nd trimester of pregnancy has an inverse correlation with preterm delivery.

Effect of bacterial vaginosis on premature rupture of membranes and related complications in pregnant women with a gestational age of 37-42 weeks

BACKGROUND

The most serious outcome of term, premature rupture of membrane and chorioamnionitis is often associated with adverse maternal and infant outcomes related to infection. This study was undertaken to determine the prevalence of bacterial vaginosis (BV) at 37-42 gestational weeks and its relationship to premature rupture of membranes.

METHOD

During an analytical descriptive prospective study, 425 pregnant women with a gestational age of 37-42 weeks were studied for prevalence of BV. Then, 304 women on the basis of having BV or not were followed up until 48 h after delivery for premature rupture of membranes.

RESULT

The rate of BV in this population was 30.5%. No significant association was found between BV and premature rupture of membranes (odds ratio 1.6, 95% CI 0.9-2.8).

CONCLUSION

BV is a common vaginitis in term pregnancy, but we could not find any relationship between BV and premature rupture of membranes at term.

Sexually transmitted infections in pregnancy: prevalence, impact on pregnancy outcomes, and approach to treatment in developing countries

Sexually transmitted infections (STIs) are common in the developing world. Management of STIs in pregnancy in many developing countries has, however, been complicated by the lack of simple and affordable diagnostic tests. This review examines the prevalence and impact on pregnancy outcome of STIs in developing countries and recommends approaches to management of STIs in pregnancy for resource poor settings.

What's new in bacterial vaginosis and trichomoniasis?

The use of biochemical profiles and new molecular microbiologic methodologies is transforming our understanding of BV. Most important is the recognition of different subgroups of women who have BV who are at variable risk of certain obstetric and gynecologic complications. New diagnostic tests may soon be available that will allow women to test self-obtained specimens. Treatment of BV has lagged, although innovative methods appear to be helpful in managing recurrent diseases.

Antibiotics for Bacterial Vaginosis or Trichomonas vaginalis in Pregnancy: A Systematic Review

OBJECTIVE

To determine whether antibiotic treatment for bacterial vaginosis or Trichomonas vaginalis during pregnancy decreases the risk of preterm birth and associated adverse outcomes.

DATA SOURCES

Pre-MEDLINE and MEDLINE (1966-2003), EMBASE (1980-2003), and the Cochrane Library were searched using the keywords "bacterial vaginosis", "Trichomonas", "Trichomonas vaginalis", "Trichomonas vaginitis", "Trichomonas infections", "pregnancy", "pregnant", "antibiotics", and "antibiotic prophylaxis".

METHODS OF STUDY SELECTION

The search produced 1,888 titles, of which 1,256 abstracts were reviewed further. Of these, 1,217 were ineligible. Inclusion criteria were the following: randomized controlled trials in which antibiotics were compared with no antibiotic or placebo, for women in the second or third trimester of pregnancy with symptomatic or asymptomatic bacterial vaginosis or Trichomonas vaginalis, intact membranes, and not in labor. Exclusion criteria were as follows: published in a language other than English, dropout rate of more than 20% of women in either group, and lack of usable outcomes. Of the 39 papers reviewed in detail, 14 studies were included in the meta-analysis.

TABULATION, INTEGRATION, AND RESULTS

One of the authors reviewed titles obtained from the searches, and 2 reviewers independently reviewed the abstracts, excluded those that were ineligible, identified eligible papers, and abstracted the data. For women with bacterial vaginosis, antibiotics reduced the risk of persistent infection but did not reduce the risk of preterm birth or the incidence of associated adverse outcomes for the general population or for any subgroup analyzed. For women with Trichomonas vaginalis, metronidazole reduced the risk of persistent infection but increased the incidence of preterm birth.

CONCLUSION

Contrary to the conclusions of 3 recent systematic reviews, we found no evidence to support the use of antibiotic treatment for bacterial vaginosis or Trichomonas vaginalis in pregnancy to reduce the risk of preterm birth or its associated morbidities in low- or high-risk women.

A descriptive correlational study of bacterial vaginosis in pregnancy and its association with preterm birth: implications for advanced practice nurses

PURPOSE

To expand on prior (often contradictory) research implicating maternal infection as a cause of preterm birth, specifically exploring whether bacterial vaginosis (BV) in pregnancy caused preterm birth in a sample of 103 women in a rural Mississippi obstetric-gynecologic clinic.

DATA SOURCES

This descriptive correlational study explored the relationship between BV and preterm birth, using retrospective chart data from a purposive sample of 103 women (for a power level of 95%) from one rural obstetric-gynecologic clinic.

CONCLUSIONS

Contrary to the majority of published research, this study did not find a positive correlation between BV and preterm birth. This unexpected result raises questions, particularly given that the preponderance (86%) of women who tested positive for BV during their pregnancy were African American, a population in which both BV and preterm birth are more prevalent.

IMPLICATIONS FOR PRACTICE

Whether to screen for BV in pregnancy is a clinically important question not only in terms of the health of mother and child but also in terms of responsible use of resources. Clear findings supporting beneficial health results for screening would dictate screening regardless of the cost. But research continues to lack consensus on the efficacy of BV screening during pregnancy in preventing adverse pregnancy outcomes. In this study, as in some of the literature, the risk of preterm birth did not correlate positively with BV during pregnancy. In the absence of that correlation, cost gains importance. Nurse practitioners (NPs) must use resources wisely, including time, laboratory tests, and medications. Although some specialists recommend screening or treating all pregnant patients for BV, the current practice of not screening or treating all pregnant patients seems warranted until definitive findings establish a conclusive correlation between BV and preterm birth.

Is bacterial vaginosis a stronger risk factor for preterm birth when it is diagnosed earlier in gestation?

OBJECTIVE

It is stated commonly that the earlier in pregnancy bacterial vaginosis is diagnosed, the greater is the increase in risk of preterm birth compared with women without bacterial vaginosis. However, this contention is based on small numbers of women.

STUDY DESIGN

In this analysis of 12,937 women who were screened for bacterial vaginosis as part of a previously conducted clinical trial, the odds ratio of preterm birth (<7 weeks of gestation) for asymptomatic bacterial vaginosis-positive versus bacterial vaginosis-negative women was evaluated among women who were screened from 8 to 22 weeks of gestation.

RESULTS

The odds ratio of preterm birth among bacterial vaginosis-positive versus bacterial vaginosis-negative women ranged from 1.1 to 1.6 and did not vary significantly according to the gestational age at which bacterial vaginosis was screened. The odds ratio for preterm birth did not vary significantly by gestational age at diagnosis when bacterial vaginosis was subdivided into Gram stain score 7 to 8 or 9 to 10.

CONCLUSION

Although bacterial vaginosis was associated with an increased risk of preterm birth, the gestational age at which bacterial vaginosis was screened for and diagnosed did not influence the increase.

A prospective cohort study of pregnancy risk factors and birth outcomes in Aboriginal women

BACKGROUND

Aboriginal women have been identified as having poorer pregnancy outcomes than other Canadian women, but information on risk factors and outcomes has been acquired mostly from retrospective databases. We compared prenatal risk factors and birth outcomes of First Nations and Métis women with those of other participants in a prospective study.

METHODS

During the 12-month period from July 1994 to June 1995, we invited expectant mothers in all obstetric practices affiliated with a single teaching hospital in Edmonton to participate. Women were recruited at their first prenatal visit and followed through delivery. Sociodemographic and clinical data were obtained by means of a patient questionnaire, and microbiological data were collected at 3 points during gestation: in the first and second trimesters and during labour. Our primary outcomes of interest were low birth weight (birth weight less than 2500 g), prematurity (birth at less than 37 weeks' gestation) and macrosomia (birth weight greater than 4000 g).

RESULTS

Of the 2047 women consecutively enrolled, 1811 completed the study through delivery. Aboriginal women accounted for 70 (3.9%) of the subjects who completed the study (45 First Nations women and 25 Métis women). Known risk factors for adverse pregnancy outcome were more common among Aboriginal than among non-Aboriginal women, including previous premature infant (21% v. 11%), smoking during the current pregnancy (41% v. 13%), presence of bacterial vaginosis in midgestation (33% v. 13%) and poor nutrition as measured by meal consumption. Although Aboriginal women were less likely than non-Aboriginal women to have babies of low birth weight (odds ratio [OR] 1.46, 95% confidence interval [CI] 0.52-4.15) or who were born prematurely (OR 1.45, 95% CI 0.57-3.72) and more likely to have babies with macrosomia (OR 2.04, 95% CI 1.03-4.03), these differences were lower and statistically nonsignificant after adjustment for smoking, cervicovaginal infection and income (adjusted OR for low birth weight 0.85, 95% CI 0.19-3.78; for prematurity 0.90, 95% CI 0.21-3.89; and for macrosomia 2.12, 95% CI 0.84-5.36).

INTERPRETATION

After adjustment for potential confounding factors, we found no statistically significant relation between Aboriginal status and birth outcome.

Natural history of bacterial vaginosis and intermediate flora in pregnancy and effect of oral clindamycin

OBJECTIVE

We sought to describe the natural history of abnormal vaginal flora in pregnancy and estimate the efficacy of oral clindamycin in eradicating it and preventing relapse.

METHODS

This was a subanalysis of a randomized trial of oral clindamycin for abnormal vaginal flora in pregnancy. All 494 enrolled women were asked to provide a vaginal smear 2 weeks after treatment and every second participant to provide further smears at 20, 24, 28, 32, and 36 weeks of gestation. We used Nugent score of Gram-stained smears to assess the cure rate among the clindamycin group and the rate of spontaneous resolution among the placebo group.

RESULTS

Posttreatment smears were available for 462 women (231 in each of the clindamycin and placebo arms). The prevalence of abnormal flora posttreatment was 10% (22 of 231) in the clindamycin group compared with 93% (214 of 231) in the placebo group (P <.001). Two hundred nineteen women obtained 4 weekly smears; slides for 84 women were lost, and results were available for 135 women (69 clindamycin, 66 placebo). In the clindamycin group, the prevalence of abnormal flora was 15% at 20 weeks of gestation and 17% at 36 weeks of gestation compared with 69% at 20 weeks of gestation and 43% at 36 weeks of gestation in the placebo group.

CONCLUSION

Oral clindamycin eradicated abnormal flora in 90% of treated pregnant women and maintained a normal flora in two thirds of women throughout pregnancy. Almost one third of untreated women in our study had spontaneous resolution of abnormal flora by 20 weeks of gestation. Because previous research has shown that spontaneous resolution does not modify the risk of preterm birth, early screening is essential.

The accuracy of various tests for bacterial vaginosis in predicting preterm birth: a systematic review

OBJECTIVE

To determine the accuracy with which various types of tests for bacterial vaginosis predict spontaneous preterm birth in pregnant women.

DATA SOURCES

Studies were identified without language restrictions through nine different databases, and manual searching of bibliographies of known primary and review articles.

STUDY SELECTION AND DATA EXTRACTION

There are four different bacterial vaginosis testing methods: Gram staining tests using either Nugent's or Spiegel's criteria, and gas liquid chromatography are laboratory based, and the fourth method uses clinical (Amsel's) criteria to diagnose bacterial vaginosis. Two reviewers independently selected studies and extracted data on their characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables of the bacterial vaginosis test results with spontaneous preterm birth as the reference standard.

DATA SYNTHESIS

Data on asymptomatic women and women with symptoms of threatened preterm labour were analysed separately. Data were pooled to produce summary estimates of likelihood ratios for positive (LR+) and negative (LR-) test results for the various types of tests.

RESULTS

There were 18 primary articles, involving altogether 17,868 women. There was unexplained heterogeneity in the meta-analyses of the accuracy results, which requires caution in their interpretation. Meta-analyses of studies testing asymptomatic women in the second trimester showed that clinical criteria had a LR+ of 0.98 (95% confidence interval 0.59 to 1.6) and a LR- of 1.00 (0.93 to 1.1), Gram staining (Nugent's criteria) had a LR+ of 1.6 (1.4 to 1.9) and a LR- of 0.9 (0.8 to 0.9), and Gram staining (Spiegel's criteria) had a LR+ of 2.4 (1.4 to 4.9) and a LR- of 0.81 (0.64 to 1.0). Among symptomatic women, Gram staining (Spiegel's criteria) had a LR+ of 1.3 (1.0 to 1.6) and LR- of 0.9 (0.7 to 1.0).

CONCLUSION

There was a lack of difference in the accuracy of the various bacterial vaginosis tests for predicting preterm birth in both asymptomatic and symptomatic women of threatened preterm labour.