Metronidazole to prevent preterm delivery in pregnant women with asymptomatic bacterial vaginosis. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units

Persistent Bacterial Vaginosis and Risk for Spontaneous Preterm Birth

OBJECTIVE

 The aim of this study was to determine the association between persistent bacterial vaginosis (BV) in pregnancy and risk for spontaneous preterm birth (sPTB).

STUDY DESIGN

 Retrospective data from IBM MarketScan Commercial Database were analyzed. Women aged between 12 and 55 years with singleton gestations were included and linked to an outpatient medications database and medications prescribed during the pregnancy were analyzed. BV in pregnancy was determined based on both a diagnosis of BV and treatment with metronidazole and/or clindamycin, and persistent treatment of BV was defined as BV in more than one trimester or BV requiring more than one antibiotic prescription. Odds ratios were calculated comparing sPTB frequencies in those with BV, or persistent BV, to women without BV in pregnancy. Survival analysis using Kaplan-Meier curves for the gestational age at delivery was also performed.

RESULTS

 Among a cohort of 2,538,606 women, 216,611 had an associated International Classification of Diseases, 9th Revision or 10th Revision code for diagnosis of BV alone, and 63,817 had both a diagnosis of BV and were treated with metronidazole and/or clindamycin. Overall, the frequency of sPTB among women treated with BV was 7.5% compared with 5.7% for women without BV who did not receive antibiotics. Relative to those without BV in pregnancy, odds ratios for sPTB were highest in those treated for BV in both the first and second trimester (1.66 [95% confidence interval [CI]: 1.52, 1.81]) or those with three or more prescriptions in pregnancy (1.48 [95% CI: 1.35, 1.63].

CONCLUSION

 Persistent BV may have a higher risk for sPTB than a single episode of BV in pregnancy.

KEY POINTS

· Persistent BV beyond one trimester may increase the risk for sPTB.. · Persistent BV requiring more than one prescription may increase the risk for sPTB.. · Almost half of antibiotic prescriptions treating BV in pregnancy are filled after 20 weeks gestation..

Copy number variants and fetal structural abnormalities in stillborn fetuses: A secondary analysis of the Stillbirth Collaborative Research Network study

OBJECTIVE

To examine the association of placental and fetal DNA copy number variants (CNVs) with fetal structural malformations (FSMs) in stillborn fetuses.

DESIGN

A secondary analysis of stillbirth cases in the Stillbirth Collaborative Research Network (SCRN) study.

SETTING

Multicenter, 59 hospitals in five geographic regions in the USA.

POPULATION

388 stillbirth cases of the SCRN study (2006-2008).

METHODS

Fetal structural malformations were grouped by anatomic system and specific malformation type (e.g. central nervous system, thoracic, cardiac, gastrointestinal, skeletal, umbilical cord and craniofacial defects). Single-nucleotide polymorphism array detected CNVs of at least 500 kb. CNVs were classified into two groups: normal, defined as no CNVs >500 kb or benign CNVs, and abnormal, defined as pathogenic or variants of unknown clinical significance.

MAIN OUTCOME MEASURES

The proportions of abnormal CNVs and normal CNVs were compared between stillbirth cases with and without FSMs using the Wald Chi-square test.

RESULTS

The proportion of stillbirth cases with any FSMs was higher among those with abnormal CNVs than among those with normal CNVs (47.5 versus 19.1%; P-value <0.001). The most common organ system-specific FSMs associated with abnormal CNVs were cardiac defects, followed by hydrops, craniofacial defects and skeletal defects. A pathogenic deletion of 1q21.1 involving 46 genes (e.g. CHD1L) and a duplication of 21q22.13 involving four genes (SIM2, CLDN14, CHAF1B, HLCS) were associated with a skeletal and cardiac defect, respectively.

CONCLUSION

Specific CNVs involving several genes were associated with FSMs in stillborn fetuses. The findings warrant further investigation and may inform counselling and care surrounding pregnancies affected by FSMs at risk for stillbirth.

Primary prevention with vaginal chlorhexidine before 16 weeks reduces the incidence of preterm birth: results of the Preterm Labor Prevention Using Vaginal Antiseptics study

BACKGROUND

Preterm labor is one of the leading causes of perinatal death and is currently considered a syndrome with many causes. One of the most important causes of preterm birth is ascending infection from bacterial vaginosis. Chlorhexidine has proven to be effective against bacterial vaginosis and against bacterial biofilms without affecting gestation.

OBJECTIVE

We aimed to evaluate the effectiveness of a universal primary prevention strategy for preterm birth using intravaginal chlorhexidine applied before 16 weeks (Preterm Labor Prevention Using Vaginal Antiseptics study).

STUDY DESIGN

We performed a prospective observational study with 2 cohorts of pregnant women that were assigned either to prevention of preterm birth by means of intravaginal chlorhexidine (Cum Laude Chlorhexidine, chlorhexidine digluconate 0.2%) before 16 weeks (n=413), or to no treatment following the usual hospital protocol (n=704). Primary outcomes were the incidence of spontaneous preterm birth before 34 and 37 weeks; the incidence of preterm birth before 34 and 37 weeks, including inductions for premature rupture of membranes; and the incidence of preterm birth before 34 and 37 weeks, including any indication for termination of pregnancy. Both cohorts were compared using Mann-Whitney and Fisher tests. Finally, a multivariable analysis, including the odds ratio was performed, adjusting for clinical parameters, to evaluate the importance of the different determinants in the prediction of preterm birth.

RESULTS

In pregnancies treated with chlorhexidine, the incidences of spontaneous preterm birth; preterm birth, including induction for premature rupture of membranas; and preterm birth, including any indication for termination of pregnancy were at 34 and 37 weeks: 0% and 0%, 0.24% and 1.69, and 2.90% and 3.15%, respectively; whereas in nontreated pregnancies, these incidences were 9% and 11%, 12% and 23%, and 35% and 43%, respectively. According to the multivariable analysis, the incidence of preterm birth among women treated with chlorhexidine before 16 weeks was halved (Odds ratio, 0.52; P<.05).

CONCLUSION

Universal treatment with vaginal chlorhexidine before 16 weeks reduces the incidence of preterm birth, especially before 34 weeks.

Reassessing Preterm Birth Prevention After the Withdrawal of 17-α Hydroxyprogesterone Caproate

The U.S. Food and Drug Administration has recently withdrawn approval for 17-α hydroxyprogesterone caproate for prevention of recurrent preterm birth, and recent studies have called into question benefits of the pessary in the setting of a short cervix. Obstetric health care professionals are once again left with limited remaining options for preterm birth prevention. This narrative review summarizes the best current evidence on the use of vaginal progesterone, low-dose aspirin, and cerclage for the prevention of preterm birth; attempts to distill possible lessons learned from studies of progesterone and pessary, as well as their implementation into practice; and highlights areas where inroads into preterm birth prevention may be possible outside of the progesterone-aspirin-cerclage paradigm.

Effectiveness and Costs of Molecular Screening and Treatment for Bacterial Vaginosis to Prevent Preterm Birth: The AuTop Randomized Clinical Trial

Importance

Bacterial vaginosis (BV) is a well-known risk factor for preterm birth. Molecular diagnosis of BV is now available. Its impact in the screening and treatment of BV during pregnancy on preterm births has not been evaluated to date.

Objective

To evaluate the clinical and economic effects of point-of-care quantitative real-time polymerase chain reaction screen and treat for BV in low-risk pregnant women on preterm birth.

Design, Setting, and Participants

The AuTop trial was a prospective, multicenter, parallel, individually randomized, open-label, superiority trial conducted in 19 French perinatal centers between March 9, 2015, and December 18, 2017. Low-risk pregnant women before 20 weeks' gestation without previous preterm births or late miscarriages were enrolled. Data were analyzed from October 2021 to November 2022.

Interventions

Participants were randomized 1:1 to BV screen and treat using self-collected vaginal swabs (n = 3333) or usual care (n = 3338). BV was defined as Atopobium vaginae (Fannyhessea vaginae) load of 108 copies/mL or greater and/or Gardnerella vaginalis load of 109 copies/mL or greater, using point-of-care quantitative real-time polymerase chain reaction assays. The control group received usual care with no screening of BV.

Main Outcomes and Measures

Overall rate of preterm birth before 37 weeks' gestation and total costs were calculated in both groups. Secondary outcomes were related to treatment success as well as maternal and neonate health. Post hoc subgroup analyses were conducted.

Results

Among 6671 randomized women (mean [SD] age, 30.6 [5.0] years; mean [SD] gestational age, 15.5 [2.8] weeks), the intention-to-treat analysis of the primary clinical and economic outcomes showed no evidence of a reduction in the rate of preterm birth and total costs with the screen and treat strategy compared with usual care. The rate of preterm birth was 3.8% (127 of 3333) in the screen and treat group and 4.6% (153 of 3338) in the control group (risk ratio [RR], 0.83; 95% CI, 0.66-1.05; P = .12). On average, the cost of the intervention was €203.6 (US $218.0) per participant, and the total average cost was €3344.3 (US $3580.5) in the screen and treat group vs €3272.9 (US $3504.1) in the control group, with no significant differences being observed. In the subgroup of nulliparous women (n = 3438), screen and treat was significantly more effective than usual care (RR, 0.62; 95% CI, 0.45-0.84; P for interaction = .003), whereas no statistical difference was found in multiparous (RR, 1.30; 95% CI, 0.90-1.87).

Conclusion and Relevance

In this clinical trial of pregnant women at low risk of preterm birth, molecular screening and treatment for BV based on A vaginae (F vaginae) and/or G vaginalis quantification did not significantly reduce preterm birth rates. Post hoc analysis suggests a benefit of screen and treat in low-risk nulliparous women, warranting further evaluation in this group.

Trial Registration

ClinicalTrials.gov Identifier: NCT02288832.

Routine screening of abnormal vaginal flora during pregnancy reduces the odds of preterm birth: a systematic review and meta-analysis

Prematurity is the leading cause of perinatal mortality and the morbidity among children under the age of 5. The prevalence of preterm birth is between 5 and 18% worldwide. Approximately 30% of preterm deliveries occur as a consequence of fetal or maternal infections. Bacterial vaginosis can increase the risk of ascending infections. However, there is no recommendation or protocol for screening of abnormal vaginal flora. The aim of this systematic review was to investigate the effectiveness of routine screening of abnormal vaginal flora during pregnancy care. We conducted our systematic search in the following databases: MEDLINE via PubMed, Embase, and Cochrane Library. Studies reporting on pregnant women with no symptoms of bacterial vaginosis were included in our analysis if they provided data on the outcome of their pregnancy. The intervention group went through screening of abnormal vaginal flora in addition to routine pregnancy care. Odds ratio (OR) with 95% confidence intervals (CIs) was used as effect size measure. From each study the total number of patients and number of events was extracted in both the intervention and control arm to calculate OR. Altogether we included 13 trials with 143,534 patients. The screening methods were Gram stain, pH screening, pH self-screening and pH screening combined with Gram stain. Regular screening of vaginal flora compared to no screening significantly reduces the odds of preterm birth before 37 weeks (8.98% vs 9.42%; OR 0.71, CI 0.57-0.87), birthweight under 2500 g (6.53% vs 7.24%; OR 0.64, CI 0.50-0.81), preterm birth before 32 weeks (1.35% vs 2.03%; OR 0.51, CI 0.31-0.85) and birthweight under 1000 g (0.86% vs 2.2%; OR 0.33, CI 0.19-0.57). In conclusion, the routine screening of abnormal vaginal flora might prevent preterm birth, extreme preterm birth, low birthweight deliveries and very low birthweight deliveries. Further research is needed to assess the problem more accurately.

Understanding and Preventing Recurring Bacterial Vaginosis: Important Considerations for Clinicians

Bacterial vaginosis (BV) is the most common vaginal infection worldwide. It is associated with an increased risk of acquisition of HIV and other sexually transmitted infections (STIs) as well as pelvic inflammatory disease and adverse birth outcomes. During BV, a polymicrobial biofilm forms on the surface of the vaginal mucosa. However, the exact etiology of BV remains controversial which has impeded significant advances in diagnosis, treatment, and prevention. Despite 30-day cure rates approaching 80% in BV-infected women treated with 7 days of oral metronidazole, recurrence within 12 months is common. This article provides a current review of the epidemiology, pathogenesis, diagnosis, and treatment of recurrent BV for practicing clinicians who commonly see women with this recurrent vaginal infection. Regarding management, we focus primarily on antimicrobial measures that may be effective. Future areas of research in this field are also discussed.

Effect of vaginal microbiota on pregnancy outcomes of women from Northern China who conceived after IVF

Objective

This study aimed to investigate the correlation between vaginal microbiota and pregnancy outcomes of women who achieved pregnancy via in vitro fertilization (IVF) in Northern China, and to determine a biomarker for evaluation of the risk of preterm births in these women.

Methods

In total, 19 women from Northern China women who conceived after IVF and 6 women who conceived naturally were recruited in this study. The vaginal samples of the healthy participants were collected throughout pregnancy, that is, during the first, second, and third trimesters. The V3-V4 region of 16S rRNA was used to analyze the vaginal microbiome, and the bioinformatic analysis was performed using QIIME Alpha and Beta diversity analysis.

Results

Either IVF group or Natural conception group, bacterial community diversities and total species number of vagnal samples from who delivered at term were significantly higher than those who delivered before term. Low abundance of vaginal bacteria indicates an increased risk of preterm delivery. Further, more abundant vaginal bacteria was found in first trimesters instead of the next two trimesters. Vignal samples collected during first trimester showed richer differences and more predictive value for pregnancy outcoes. In addition, the diversity of the vaginal bacterial community decreased as the gestational age increased, in all samples. Alloscardovia was only found in participants who conceived after IVF, and the percentage of Alloscardovia in viginal samples of normal delivery group is much higher than the samples from preterm delivery group.Vobrio specifically colonized in vagina of pregnant woman in AFT group (those who conceived after IVF (A), first trimester (F), and delivered at term (T)) and Sporosarcina was detected only in women with AFT and AST (those who conceived after IVF (A), second trimester (S), and delivered at term (T)). These data indicates that Alloscardovia, Vobrio and Sporosarcina have great potential in predicting pregnancy outcomes who pregnanted by vitro fertilization.

Conclusions

Vaginal microbiota were more stable in women who conceived naturally and those who carried pregnancy to term. Oceanobacillus might act as a positive biomarker, whereas Sulfurospirillum and Propionispira may act as negative biomarkers for the risk of preterm birth.

The Effect of Sexual Intercourse during Pregnancy on Preterm Birth: Prospective Single-Center Cohort Study in Japan

Several studies in Europe and the United States have shown that sexual intercourse (SI) during pregnancy is not associated with preterm birth. However, it is unclear whether these findings apply to pregnant Japanese women. The aim of this prospective cohort study was to elucidate the influence of SI during pregnancy on preterm birth in Japan. A total of 182 women who underwent antenatal care and delivery were included in this study. The frequency of SI was assessed using a questionnaire, and its association with preterm birth was analyzed. The results showed that SI during pregnancy was associated with a significantly higher cumulative preterm birth rate (p = 0.018), which was more pronounced for SI more than once a week (p < 0.0001). Multivariate analysis showed that SI, bacterial vaginosis in the second trimester, previous preterm birth, and smoking during pregnancy were independent risk factors for preterm birth. The combination of SI and second trimester bacterial vaginosis was associated with a 60% preterm birth rate, whereas either factor alone was associated with a lower rate, suggesting a synergistic effect (p < 0.0001). Future studies are needed to investigate the effect of prohibiting SI in pregnant women with bacterial vaginosis on preterm birth.

Antenatal interventions to reduce risk of low birth weight related to maternal infections during pregnancy

BACKGROUND

Maternal infections during pregnancy have been linked to increased risk of adverse birth outcomes, including low birth weight (LBW), preterm birth (PTB), small for gestational age (SGA), and stillbirth (SB).

OBJECTIVES

The purpose of this article was to summarize evidence from published literature on the effect of key interventions targeting maternal infections on adverse birth outcomes.

METHODS

We searched MEDLINE, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and CINAHL Complete between March 2020 and May 2020 with an update to cover until August 2022. We included randomized controlled trials (RCTs) and reviews of RCTs of 15 antenatal interventions for pregnant women reporting LBW, PTB, SGA, or SB as outcomes.

RESULTS

Of the 15 reviewed interventions, the administration of 3 or more doses of intermittent preventive treatment in pregnancy with sulphadoxine-pyrimethamine [IPTp-SP; RR: 0.80 (95% CI: 0.69, 0.94)] can reduce risk of LBW compared with 2 doses. The provision of insecticide-treated bed nets, periodontal treatment, and screening and treatment of asymptomatic bacteriuria may reduce risk of LBW. Maternal viral influenza vaccination, treatment of bacterial vaginosis, intermittent preventive treatment with dihydroartemisinin-piperaquine compared with IPTp-SP, and intermittent screening and treatment of malaria during pregnancy compared with IPTp were deemed unlikely to reduce the prevalence of adverse birth outcomes.

CONCLUSIONS

At present, there is limited evidence from RCTs available for some potentially relevant interventions targeting maternal infections, which could be prioritized for future research.

Antibiotic treatment of bacterial vaginosis to prevent preterm delivery: Systematic review and individual participant data meta-analysis

BACKGROUND

Bacterial vaginosis (BV) increases preterm delivery (PTD) risk, but treatment trials showed mixed results in preventing PTD.

OBJECTIVES

Determine, using individual participant data (IPD), whether BV treatment during pregnancy reduced PTD or prolonged time-to-delivery.

DATA SOURCES

Cochrane Systematic Review (2013), MEDLINE, EMBASE, journal searches, and searches (January 2013-September 2022) ("bacterial vaginosis AND pregnancy") of (i) clinicaltrials.gov; (ii) Cochrane Central Register of Controlled Trials; (iii) World Health Organization International Clinical Trials Registry Platform Portal; and (iv) Web of Science ("bacterial vaginosis").

STUDY SELECTION AND DATA EXTRACTION

Studies randomising asymptomatic pregnant individuals with BV to antibiotics or control, measuring delivery gestation. Extraction was from original data files. Bias risk was assessed using the Cochrane tool. Analysis used "one-step" logistic and Cox random effect models, adjusting gestation at randomisation and PTD history; heterogeneity by I2 . Subgroup analysis tested interactions with treatment. In sensitivity analyses, studies not providing IPD were incorporated by "multiple random-donor hot-deck" imputation, using IPD studies as donors.

RESULTS

There were 121 references (96 studies) with 23 eligible trials (11,979 participants); 13 studies (6915 participants) provided IPD; 12 (6115) were incorporated. Results from 9 (4887 participants) not providing IPD were imputed. Odds ratios for PTD for metronidazole and clindamycin versus placebo were 1.00 (95% CI 0.84, 1.17), I2  = 62%, and 0.59 (95% CI 0.42, 0.82), I2  = 0 before; and 0.95 (95% CI 0.81, 1.11), I2  = 59%, and 0.90 (95% CI: 0.72, 1.12), I2  = 0, after imputation. Time-to-delivery did not differ from null with either treatment. Including imputed IPD, there was no evidence that either drug was more effective when administered earlier, or among those with a PTD history.

CONCLUSIONS

Clindamycin, but not metronidazole, was beneficial in studies providing IPD, but after imputing data from missing IPD studies, treatment of BV during pregnancy did not reduce PTD, nor prolong pregnancy, in any subgroup or when started earlier in gestation.

Parental pre-pregnancy body mass index and risk of low birth weight in offspring: A prospective cohort study in central China

Background

Low birth weight (LBW) is one of the most common adverse pregnancy outcomes. Previous studies have consistently shown that maternal body mass index (BMI) status before and during pregnancy is associated with LBW. However, previous studies lacked an association between paternal BMI and the conjunction effect of a couple's BMI and LBW in the offspring. Therefore, we established a cohort of pre-pregnancy couples to prospectively assess the relationship between maternal and paternal pre-pregnancy BMI and offspring LBW, very low birth weight (VLBW), and extremely low birth weight (ELBW).

Methods

A prospective cohort study was established in Central China. A total of 34,104 pregnant women with singleton pregnancies at 8-14 gestational weeks and their husbands were finally enrolled and followed to 3 months postpartum. The multivariate logistic regression and restrictive cubic spline model were used to explore the relationship between parental pre-pregnancy BMI and the risk of LBW, VLBW, and ELBW in offspring.

Results

Of the 34,104 participants, maternal pre-pregnancy overweight and obesity were associated with a higher risk of LBW (overweight: OR = 1.720, 95% CI = 1.533 ~ 1.930; obesity: OR = 1.710, 95% CI = 1.360 ~ 2.151), VLBW (overweight: OR = 2.283, 95% CI = 1.839 ~ 2.834; obesity: OR = 4.023, 95% CI = 2.855 ~ 5.670), and ELBW (overweight: OR = 3.292, 95% CI = 2.151 ~ 5.036; obesity: OR = 3.467, 95% CI = 1.481 ~ 8.115), while underweight was associated with a higher risk of LBW (OR = 1.438, 95% CI = 1.294 ~ 1.599) and a lower risk of ELBW (OR = 0.473, 95% CI = 0.236 ~ 0.946). Paternal pre-pregnancy overweight and obesity were associated with a higher risk of LBW (overweight: OR = 1.637, 95% CI = 1.501 ~ 1.784; obesity: OR = 1.454, 95% CI = 1.289 ~ 1.641) and VLBW (overweight: OR = 1.310, 95% CI = 1.097 ~ 1.564; obesity: OR = 1.320, 95% CI = 1.037 ~ 1.681), while underweight was associated with a lower risk of LBW (OR = 0.660, 95% CI = 0.519 ~ 0.839). Parents who were both excessive-weights in pre-pregnancy BMI, as well as overweight mothers and normal-weight fathers before pre-pregnancy, were more likely to have offspring with LBW, VLBW, and ELBW. Dose-response relationship existed between parental pre-pregnancy and LBW, VLBW, and ELBW, except for paternal BMI and ELBW.

Conclusions

Parental pre-pregnancy BMI was associated with the risk of LBW in offspring. Management of weight before pregnancy for couples might help reduce their adverse pregnancy outcomes in future intervention studies.

Vaginal microbiota in women with spontaneous preterm labor versus those with term labor in Kenya: a case control study

Background

Preterm birth is a global problem with about 12% of births in sub-Saharan Africa occurring before 37 weeks of gestation. Several studies have explored a potential association between vaginal microbiota and preterm birth, and some have found an association while others have not. We performed a study designed to determine whether there is an association with vaginal microbiota and/or placental microbiota and preterm birth in an African setting.

Methods

Women presenting to the study hospital in labor with a gestational age of 26 to 36 weeks plus six days were prospectively enrolled in a study of the microbiota in preterm labor along with controls matched for age and parity. A vaginal sample was collected at the time of presentation to the hospital in active labor. In addition, a placental sample was collected when available. Libraries were constructed using PCR primers to amplify the V6/V7/V8 variable regions of the 16S rRNA gene, followed by sequencing with an Illumina MiSeq machine and analysis using QIIME2 2022.2.

Results

Forty-nine women presenting with preterm labor and their controls were enrolled in the study of which 23 matched case–control pairs had sufficient sequence data for comparison. Lactobacillus was identified in all subjects, ranging in abundance from < 1% to > 99%, with Lactobacillus iners and Lactobacillus crispatus the most common species. Over half of the vaginal samples contained Gardnerella and/or Prevotella; both species were associated with preterm birth in previous studies. However, we found no significant difference in composition between mothers with preterm and those with full-term deliveries, with both groups showing roughly equal representation of different Lactobacillus species and dysbiosis-associated genera. Placental samples generally had poor DNA recovery, with a mix of probable sequencing artifacts, contamination, and bacteria acquired during passage through the birth canal. However, several placental samples showed strong evidence for the presence of Streptococcus species, which are known to infect the placenta.

Conclusions

The current study showed no association of preterm birth with composition of the vaginal community. It does provide important information on the range of sequence types in African women and supports other data suggesting that women of African ancestry have an increased frequency of non-Lactobacillus types, but without evidence of associated adverse outcomes.

Preterm Birth Therapies to Target Inflammation

Preterm birth (PTB; defined as delivery before 37 weeks of pregnancy) is the leading cause of morbidity and mortality in infants and children aged <5 years, conferring potentially devastating short‐ and long‐term complications. Despite extensive research in the field, there is currently a paucity of medications available for PTB prevention and treatment. Over the past few decades, inflammation in gestational tissues has emerged at the forefront of PTB pathophysiology. Even in the absence of infection, inflammation alone can prematurely activate the main components of parturition resulting in uterine contractions, cervical ripening and dilatation, membrane rupture, and subsequent PTB. Mechanistic studies have identified critical elements of the complex inflammatory molecular pathways involved in PTB. Here, we discuss therapeutic options that target such key mediators with an aim to prevent, postpone, or treat PTB. We provide an overview of more traditional therapies that are currently used or being tested in humans, and we highlight recent advances in preclinical studies introducing novel approaches with therapeutic potential. We conclude that urgent collaborative action is required to address the unmet need of developing effective strategies to tackle the challenge of PTB and its complications.

Maternal pre-pregnancy/early-pregnancy smoking and risk of congenital heart diseases in offspring: A prospective cohort study in Central China

Background

Prior studies suggested that maternal smoking before and during pregnancy could be associated with increased risks of congenital heart diseases (CHDs) in offspring. However, the results were inconsistent, and the existence of a causal relationship was not confirmed. Our study aimed to estimate the associations of maternal active and passive smoking during the pre-pregnancy/early-pregnancy period with CHDs as well as its common phenotypes in offspring.

Methods

This study was based on data from a prospective cohort study conducted in Central China. A total of 49 158 eligible pregnant women between the 8th and 14th weeks of gestation were invited to join the cohort and were planned to be followed up until 3 months postpartum. The exposure of interest was maternal smoking status, including active and passive smoking status in 3 months before pregnancy as well as in early pregnancy. Self-reported maternal smoking status was ascertained via an in-person interview after recruitment. CHDs were diagnosed by pediatric cardiologists and classified according to ICD-10. Multivariable Poisson regression models were used to estimate the relative risks (RRs) with 95% confidence intervals (CIs) of all CHDs and their common phenotypes associated with maternal smoking status, adjusting for potential confounding factors identified by directed acyclic graphs.

Results

CHDs were diagnosed in 564 children. After adjusting for potential confounding factors and comparing with the unexposed groups, CHDs incidence was 165% higher (adjusted RR = 2.65; 95% CI = 1.76-3.98) in offspring exposed to maternal active smoking in 3 months before pregnancy, 69% higher (adjusted-RR = 1.69; 95% CI = 1.39-2.05) in offspring exposed to maternal passive smoking in 3 months before pregnancy, 133% higher (adjusted RR = 2.33; 95% CI = 1.46-3.70) for offspring exposed to maternal active smoking in early pregnancy, and 98% higher (adjusted-RR = 1.98; 95% CI = 1.56-2.51) for offspring exposed to maternal passive smoking in early pregnancy. More specifically, the offspring exposed to maternal active smoking in early pregnancy had the highest risk of Tetralogy of Fallot (adjusted RR = 9.84; 95% CI = 2.49-38.84). These findings were recapitulated in analyses that further adjusted for other behaviour variables apart from the characteristic being assessed and were also confirmed by sensitivity analyses.

Conclusions

Our findings add to the existing body of evidence that implicates maternal pre-pregnancy/early-pregnancy smoking as a significant risk factor for CHDs and their select phenotypes.

Diagnosis and Management of Bacterial Vaginosis: Summary of Evidence Reviewed for the 2021 Centers for Disease Control and Prevention Sexually Transmitted Infections Treatment Guidelines

In preparation for the 2021 Centers for Disease Control and Prevention (CDC) sexually transmitted infections (STIs) treatment guidelines, the CDC convened an advisory group in 2019 to examine recent literature addressing updates in the epidemiology, diagnosis, and management of STIs. This article summarizes recent data in each of these key topic areas as they pertain to bacterial vaginosis (BV), the most common cause of vaginal discharge. The evidence reviewed primarily focused on updates in the global epidemiology of BV, risk factors for BV, data supportive of sexual transmission of BV-associated bacteria, BV molecular diagnostic tests, and novel treatment regimens. Additionally, recent literature on alcohol abstinence in the setting of 5-nitroimidazole use was reviewed.

Population attributable fractions for risk factors for spontaneous preterm births in 81 low- and middle-income countries: A systematic analysis

Background

Complications associated with preterm birth (PTB) are the largest contributor to under-five mortality globally. Success in reaching the Sustainable Development Goal target requires identifying potentially modifiable risk factors for PTB, estimating the relative importance of these risk factors, and identifying/implementing effective prevention strategies to address them.

Methods

We conducted a literature review to define risk relationships and estimate prevalence for established risk factors for spontaneous PTB (sPTB). We then estimated population attributable fractions (PAF) for the sPTB risk factors identified in the review as statistically significant for the 81 low- and middle-income (LMIC) countries included in the Countdown 2030 initiative. We summed country-level findings to produce PAFs for each risk factor and regional estimates for sub-Saharan Africa and South Asia.

Results

Forty-four potential sPTB risk factors were identified. and the final analysis included twenty-four risk factors with evidence of significant associations with sPTB. A second model with three additional risk factors with borderline insignificant associations was also run. Taken together, the twenty-four risk factors had a total PAF of 73% for all 81 countries and 77% and 72% of sPTB in sub-Saharan Africa and South Asia, respectively. For all countries, maternal undernutrition had the highest PAF (17.5%), followed by maternal infections (16.6%), environmental exposures (16%) and pregnancy history (8.7%).

Conclusions

While multiple risk factors contribute to sPTB, no single risk factor addresses a predominant fraction, and 27% of spontaneous preterm births are not associated with risk factors that we identified. Despite the significant role of preterm birth in child survival, there are major data gaps in LMIC settings. Furthermore, there is a paucity of evidence for effective interventions to prevent preterm birth. Preventing sPTB requires understanding underlying mechanisms leading to sPTB in different populations, and the identification/implementation of effective interventions.

Pre-Pregnancy Body Mass Index and Risk of Macrosomia and Large for Gestational Age Births with Gestational Diabetes Mellitus as a Mediator: A Prospective Cohort Study in Central China

This study aimed to examine the risk of macrosomia and large for gestational age (LGA) births in relation to maternal pre-pregnancy body mass index (BMI) status mediated through gestational diabetes mellitus (GDM). This prospective study included 34,104 singleton pregnancies at 8–14 weeks of gestation. The interesting outcomes were macrosomia (≥4000 g) and LGA (≥90th percentile). Mediation analyses were conducted using log-binomial regression adjusted for age, education, parity, fetal sex, and gestational weight gain. The proportion mediated was estimated based on the risk difference scale, and the E-value was utilized to assess potential confounders. Overall, 15.9% of women had GDM, and there were 4.0% macrosomia and 9.9% LGA births. The proportion mediated by GDM on macrosomia was up to 40% among obese women, and the estimate of the total effect was 6.18 (95% CI: 5.26–7.26), of the natural direct effect was 4.10 (95% CI: 3.35–4.99), and of the natural indirect effect was 1.51 (95% CI: 1.31–1.76). Likewise, among overweight women, the proportion mediated by GDM on macrosomia was up to 40%. Furthermore, consistent findings were evident for the outcome of LGA births. Pre-pregnancy overweight/obesity increased the risk of macrosomia and LGA births independently and partly mediated by GDM.

Antimicrobial Resistance Pattern in E. coli Isolated from Placental Tissues of Pregnant Women in Low-Socioeconomic Setting of Pakistan

Infections during pregnancy can culminate in adverse pregnancy outcomes, including preterm birth (PTB). Pakistan is among the top ten nations with high PTB-associated neonatal mortality rates, where access to prenatal as well as neonatal care is only afforded by the privileged few. Societal stigma further discourages women seeking healthcare for minor infections. Microbial pathogens associated with genitourinary infections can lead to gestational complications culminating in earlier onset of labor. In this study, association of Escherichia coli (E. coli) with PTB in Pakistani women of low-socioeconomic status is examined. 57 paired vaginal swabs and placenta samples from mothers with full term and preterm deliveries were collected and processed for isolation and molecular characterization of extraintestinal pathogenic E. coli (ExPEC). ExPEC isolated from vaginal swabs and placenta showed phylotype B2 being most prevalent (Vagina n = 3 (9), 33%) (Placenta n = 4 (12), 33%) in preterm cases followed by phylotype B1 (Vagina n = 2 (9), 22%) (Placenta n = 3 (12), 25%) and untypeable strains. Antibiotic susceptibility profiling showed a large percentage of resistant isolates to multiple antibiotics, including carbapenem and included extended-spectrum beta-lactamase (ESBL) producers. Our study is the first to report different phylotypes of E. coli from placental tissues in preterm deliveries which may be a cause for concern for maternal and neonatal health. ExPEC from vaginal swabs and placental of females delivering preterm shows the pathogenic phylotype B2 dominance with a large percentage of isolates resistant to multiple antibiotics, including carbapenem and included ESBL producers. The placental isolates may indicate ascending infection from vagina or urinary tract which may lead to preterm birth.

Effect of maternal alcohol consumption during the pre-pregnancy/early-pregnancy period on congenital heart disease: A prospective cohort study in Central China

Evidence of associations between maternal alcohol consumption and congenital heart disease (CHD) are mixed. Previous studies have been potentially biased due to recall bias or unmeasured confounding. This study aimed to examine the association of maternal alcohol consumption in 3 months before pregnancy and in early pregnancy with risks of offspring congenital heart disease (CHD) and its seven common subtypes. A prospective cohort study was conducted in Central China. From 03/13/2013 to 12/31/2019, a total of 44,048 pregnant women with singleton pregnancies at 8-14 gestational weeks were included and followed to 3 months postpartum. 564 births were diagnosed with CHD at the end of follow-up. Multivariable modified Poisson regression models were used to estimate the relative risks (RRs) of CHD in offspring exposed to maternal alcohol consumption during the pre-pregnancy and early-pregnancy period, adjusting for confounders identified by directed acyclic graphs. In the multivariable analyses, increased risks of CHDs were found in offspring exposed to maternal alcohol consumption both in 3 months before pregnancy (adjusted-RR:3.14; 95% confidence intervals[CIs]:2.30-4.28) and in early pregnancy (adjusted-RR:1.86; 95%CIs:1.13-3.05). More specifically, the offspring exposed to maternal alcohol consumption in 3 months before pregnancy had the highest increased risk of Tetralogy of Fallot (adjusted-RR:8.62; 95%CIs:3.61-20.61). These findings persisted in analyses that were further adjusted for the other behavior variables other than the characteristic being assessed, and were also confirmed by sensitivity analyses. Our study supports the need for continued efforts for public health messages surrounding the potential risks of alcohol consumption prior to or during pregnancy.

Maternal Viral Infection in Early Pregnancy and Risk of Congenital Heart Disease in Offspring: A Prospective Cohort Study in Central China

PURPOSE

To examine the associations of maternal virus infection in early pregnancy with risk of offspring congenital heart disease (CHD) and its seven common subtypes including atrial septal defect, ventricular septal defect, atrioventricular septal defect, patent ductus arteriosus, Tetralogy of Tallot, pulmonary stenosis, and transposition of the great arteries.

PATIENTS AND METHODS

A prospective cohort study was conducted in Central China. A total of 44,048 pregnant women with singleton pregnancies at 8-14 gestational weeks were finally included and followed to 3 months postpartum. Serum was tested for virus infection including hepatitis B virus (HBV), coxsackievirus-B, human cytomegalovirus (HCMV), herpes simplex virus (HSV), and rubella virus. Multivariable modified Poisson regression models were used to estimate the relative risks (RRs) of all CHDs as well as seven common subtypes of CHD in offspring of pregnant women with different types of virus infection in early pregnancy, adjusting for confounders identified by directed acyclic graphs.

RESULTS

At the end of follow-up, 564 births were diagnosed with CHD. Multivariable analyses showed that the presence of maternal viral infection in early pregnancy was independently associated with increased risks of CHD in offspring, with an adjusted relative risk of 2.21 (95% CI: 1.66-2.95) for HBV infection, 2.21 (95% CI: 1.63-3.00) for coxsackievirus-B infection, 3.12 (95% CI: 2.44-3.98) for HCMV infection, and 2.62 (95% CI: 1.95-3.51) for rubella virus infection. More specifically, the offspring of pregnant women with HCMV infection had the highest increased risk of patent ductus arteriosus (RR=10.50, 95% CI: 6.24-17.66). These findings persisted in analyses that were further adjusted for the other virus of interest in this study.

CONCLUSION

Our study proposed evidence that maternal virus infection in early pregnancy, including HBV, coxsackievirus-B, HCMV, and rubella virus, was implicated in CHD, although more studies remain needed to verify the results, especially associations in specific CHD phenotypes.

OUP accepted manuscript

Objectives

Methods

Results

Conclusions

Quality of life and long-term clinical outcome following robot-assisted radical trachelectomy

Quality of Life and long-term clinical outcome following robot-assisted radical trachelectomy.

OBJECTIVES

To evaluate quality of life (QoL) and long-term clinical outcome following robot-assisted radical trachelectomy (RRT).

STUDY DESIGN

Prospectively retrieved clinical data were rereviewed on all women planned for a fertility sparing RRT for early stage cervical cancer at Skåne University Hospital, Sweden between 2007 and 2020. QoL was assessed using the validated questionnaires EORTC QLQ-C30, QLQ-CX24 and the Swedish LYMQOL.

RESULTS

Data was analyzed from 49 women, 42 with a finalised RRT and seven with an aborted RRT due to nodal metastases (n = 3) or insufficient margins (n = 4). At a median follow-up time of 54 months one recurrence (2%) occurred (aborted RRT). According to QLQ-C30 the median global health status score was 75. The disease specific QLQ-C24 showed an impact on symptoms related to sexual function where sexual/vaginal functioning had a median score of 25 and 48% of patients reported worry that sex would cause physical pain. Despite this the functional items sexual activity and sexual enjoyment both had a median score of 66.7. Lymphoedema was reported in 45%, where 9% reported severe symptom with an impact on their QoL. No intraoperative complications and no postoperative complications ≥ Clavien Dindo grade III were observed. Twenty-two of 28 (79%) women who attempted to conceive were successful. A metronidazole/no intercourse regimen was applied between GW 15 + 0-21 + 6 in 26 of 28 pregnancies beyond first trimester resulting in a 92% term (≥GW 36 + 0) delivery rate.

CONCLUSIONS

Although robot-assisted radical trachelectomy in this cohort was associated with a low recurrence rate, a high fertility rate and an exceptionally high term delivery rate, women's quality of life was affected postoperatively, particularly with regards to their sexual well-being and lymphatic side-effects.

Prevalence, risk factors and adverse pregnancy outcomes of second trimester bacterial vaginosis among pregnant women in Bukavu, Democratic Republic of the Congo

BACKGROUND

Bacterial vaginosis (BV) is the most common gynecological condition in women of reproductive age and associated with adverse pregnancy outcomes. In the Democratic Republic of the Congo (DRC), neonatal mortality rate is as high as 2.8 percent with preterm birth (PTB) and low birth weight (LBW) as leading causes. Because no studies have addressed BV in DRC, we aimed to investigate the prevalence of BV, the risk factors and the association between BV and adverse pregnancy outcomes in a population of pregnant women from Bukavu, DRC.

METHODS

A total of 533 pregnant women in the second trimester of pregnancy were recruited in the Provincial Reference Hospital of Bukavu, DRC, between January and October 2017, and followed until delivery. Clinical and sociodemographic data of mother and newborn, and data on (vaginal) hygiene practices, sexual behavior and reproductive history were collected. BV was diagnosed by Nugent scoring of Gram-stained vaginal smears. Two multivariate regression models were built to identify risk factors for BV and to investigate BV as a risk factor for adverse pregnancy outcomes.

RESULTS

The prevalence of BV was 26.3% and approximately half of the women with BV were asymptomatic. Independent risk factors for BV were the use of alternatives to water for intravaginal washing, concurrent partners, unemployed status, the presence of vaginal Candida and clay consumption. BV was independently associated with both LBW and PTB of an infant with LBW.

CONCLUSION

The prevalence of BV in Bukavu is high but in line with the global average. BV was associated with adverse pregnancy outcomes in our study population. Hence, research on modifiable risk factor-based interventions to reduce the prevalence of BV, and on screening/treatment of BV during antenatal care should be explored to reduce neonatal mortality and morbidity.

Differential impact of abnormal vaginal colonization on perinatal outcome and association with early-onset neonatal sepsis: preterm labor vs. preterm premature rupture of membrane

OBJECTIVE

The purpose of this study was to check whether the impact of abnormal vaginal colonization on perinatal outcomes would be different in patients with preterm labor (PTL) and premature membrane rupture (PPROM). We also sought to determine the concordance rate of microorganisms isolated from the maternal vagina and neonatal blood in cases of early-onset neonatal sepsis (EONS) in PTL and PPROM.

METHODS

This retrospective study included 996 singleton pregnancies who were admitted to the high risk care unit of our institution due to PTL (n = 519) or PPROM (n = 477) and underwent vaginal culture examination at admission between January 2005 and April 2019. Abnormal vaginal colonization was defined upon isolation of aerobic microorganisms. The maternal baseline characteristics, delivery, and neonatal outcomes were compared according to the presence or absence of abnormal vaginal flora, both in PTL and PPROM.

RESULTS

The rate of abnormal vaginal colonization in PTL and PPROM was 17.0 and 21.4%, respectively. Both in PTL and PPROM, the gestational age at admission was lower in the abnormal vaginal colonization group (PTL, 27.2 ± 3.5 vs. 28.2 ± 3.5 weeks, p = .024; PPROM, 26.1 ± 5.3 vs. 27.5 ± 4.5 weeks, p = .007). Multivariable analysis demonstrated that the group with abnormal bacteria in PPROM but not in PTL had a significantly higher rate of EONS than the group without abnormal bacteria after adjustment for confounders including gestational age at admission (PPROM, odds ratio, OR [95% confidence interval, CI]: 4.172 [1.426-12.206]; PTL, OR [95% CI]: 0.661 [0.079-5.505]). Concordance analysis showed that the maternal vaginal bacteria colonization by Escherichia coli (5.9 vs. 0.5%, p = .033) and Staphylococcus aureus (14.3 vs. 0.2%, p = .032) in PPROM was significantly correlated with the microorganisms from the neonatal blood culture EONS cases. In PTL, no specific microorganisms showed concordance between maternal vaginal bacteria and microorganisms causing EONS.

CONCLUSION

Our data showed that maternal vaginal colonization in PPROM, but not in PTL, is an independent risk factor for EONS.

A combination of second trimester oral metronidazole and no sexual intercourse during second and third trimester may reduce late miscarriage and premature delivery after fertility sparing radical trachelectomy

OBJECTIVES

Women with a previous trachelectomy have an increased risk of premature delivery and second trimester miscarriage. In this study we aim to evaluate factors and regimes possibly affecting the risk for prematurity following fertility sparing robotic radical trachelectomy (RRT) in cervical cancer.

METHODS

A retrospective study of the reproductive outcome following RRT with a cervical cerclage performed at one of four academic centers between 2007 and 2019. Factors possibly related to premature delivery, such as postoperative non-pregnant cervical length, previous vaginal deliveries, preservation of the uterine arteries, and the use of a second trimester oral metronidazole/no sexual intercourse regime, were assessed.

RESULTS

109 women remained for analyses after excluding recurrences before pregnancy (n = 8), secondary hysterectomy (n = 2), and women with less than six months follow up (n = 10). 74 pregnancies occurred in 52/71 women attempting to conceive, 56 of which developed past the first trimester. Two of 22 women (9%) who were prescribed an oral metronidazole regime (400 mg × 2 from gestational week 15 + 0 to 21 + 6 and abstaining from sexual intercourse for the duration of the pregnancy) had a premature delivery, compared with 13/31 (42%) where the regime was not applied (p = 0.009). The association remained after regression analyses including possible contributing factors as of above, none of which associated with prematurity at regression analyses (p = 0.001).

CONCLUSIONS

The observed four-fold reduction in premature delivery indicates that an oral metronidazole/no sexual intercourse regime may reduce second trimester miscarriage and premature deliveries following an RRT. No association was observed for other investigated factors.

Prediction and Prevention of Spontaneous Preterm Birth: ACOG Practice Bulletin, Number 234

Preterm birth is among the most complex and important challenges in obstetrics. Despite decades of research and clinical advancement, approximately 1 in 10 newborns in the United States is born prematurely. These newborns account for approximately three-quarters of perinatal mortality and more than one half of long-term neonatal morbidity, at significant social and economic cost (1-3). Because preterm birth is the common endpoint for multiple pathophysiologic processes, detailed classification schemes for preterm birth phenotype and etiology have been proposed (4, 5). In general, approximately one half of preterm births follow spontaneous preterm labor, about a quarter follow preterm prelabor rupture of membranes (PPROM), and the remaining quarter of preterm births are intentional, medically indicated by maternal or fetal complications. There are pronounced racial disparities in the preterm birth rate in the United States. The purpose of this document is to describe the risk factors, screening methods, and treatments for preventing spontaneous preterm birth, and to review the evidence supporting their roles in clinical practice. This Practice Bulletin has been updated to include information on increasing rates of preterm birth in the United States, disparities in preterm birth rates, and approaches to screening and prevention strategies for patients at risk for spontaneous preterm birth.

Marijuana Use during Pregnancy and Preterm Birth: A Prospective Cohort Study

OBJECTIVE

The aim of this study is to estimate the association between marijuana use during pregnancy and total, spontaneous and indicated preterm birth.

STUDY DESIGN

Prospective cohort study of women receiving antenatal care at The Ohio State University from 2010 to 2015. Marijuana use was assessed by questionnaire, record abstraction, and urine toxicology. Women were followed through the end of pregnancy. Relative risks were assessed with Poisson regression and time to delivery with proportional hazard models.

RESULTS

Of 363 eligible women, 119 (33%) used marijuana in pregnancy by at least one measure. In this high-risk cohort, preterm birth occurred to 36.0% of users and 34.6% of nonusers (p = 0.81). The unadjusted relative risk of all preterm birth was 1.06 (95% confidence interval [CI]: 0.76-1.47); the adjusted relative risk was similar 1.04 (95% CI: 0.72-1.50). Spontaneous preterm birth was nonsignificantly elevated among users before 1.32 (95% CI: 0.89-1.96), and after 1.21 (95% CI: 0.76-1.94) adjustment. Indicated preterm birth was nonsignificantly reduced before 0.52 (95% CI: 0.22-1.23) and after 0.75 (95% CI: 0.29-2.15) adjustment. The unadjusted hazard ratio (HR) for time to preterm birth was 1.26 (95% CI: 0.84-2.00); the adjusted HR was 1.32 (95% CI: 0.80-2.07). Both unadjusted 1.77 (95% CI: 1.06-2.93) and adjusted 2.16 (95% CI: 1.16-4.02) HRs for spontaneous preterm birth were significantly elevated, primarily due to an increased risk of spontaneous birth <28 weeks among users. The unadjusted and adjusted HRs for time to indicated preterm birth were 0.69 (95% CI: 0.33-1.43) and 0.58 (95% CI: 0.23-1.46).

CONCLUSION

Marijuana use was not associated with total preterm birth in this cohort, suggesting that among women already at high risk of preterm birth, marijuana does not increase risk further. However, there was a suggestion that pregnant women who use marijuana may deliver earlier, particularly from spontaneous preterm birth, than women who do not use marijuana.

KEY POINTS

· Marijuana was not associated with risk of all preterm birth.. · Marijuana was not associated with reduced time to delivery.. · However, users had reduced time to spontaneous preterm birth..

Sexually Transmitted Infections Treatment Guidelines, 2021

These guidelines for the treatment of persons who have or are at risk for sexually transmitted infections (STIs) were updated by CDC after consultation with professionals knowledgeable in the field of STIs who met in Atlanta, Georgia, June 11–14, 2019. The information in this report updates the 2015 guidelines. These guidelines discuss 1) updated recommendations for treatment of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis; 2) addition of metronidazole to the recommended treatment regimen for pelvic inflammatory disease; 3) alternative treatment options for bacterial vaginosis; 4) management of Mycoplasma genitalium; 5) human papillomavirus vaccine recommendations and counseling messages; 6) expanded risk factors for syphilis testing among pregnant women; 7) one-time testing for hepatitis C infection; 8) evaluation of men who have sex with men after sexual assault; and 9) two-step testing for serologic diagnosis of genital herpes simplex virus. Physicians and other health care providers can use these guidelines to assist in prevention and treatment of STIs.

Investigating the efficacy and safety of metronidazole during pregnancy; A systematic review and meta-analysis

OBJECTIVE

We aimed to review and analyze studies focusing on the efficacy of metronidazole in reducing the risk of preterm birth and the safety of metronidazole taking into account the different doses, duration of treatment and routes of administration.

STUDY DESIGNS

Embase, Cochrane Library and PubMed were searched up to 29 July 2019 to identify studies assessing metronidazole exposure during pregnancy. Additional studies were identified from reference lists of retrieved papers. Measured outcomes were preterm births (<37 weeks of gestation) and associated delivery outcomes such as spontaneous abortions (≤ 20 weeks of gestation), stillbirths (≥20 weeks of gestation) and low birth weight (<2500 g) irrespective of the period of exposure and major malformations after first-trimester exposure. Overall effect estimates for RCTs and observational studies were calculated using the random-effects model and pooled using Risk Ratios (RR) and Odds Ratios (OR) respectively. ROB-2 and ROBINS-I tool were used to assess Risk of Bias for RCTs and observational studies, respectively.

RESULTS

Twenty-four studies (17 observational studies and 7 RCTs) were selected. Pooled RR was 1.10 (95 % CI 0.78-1.55; n = 7; I2 = 72 %) for preterm birth. Subgroup analysis found RR 1.67; 95 % CI 1.07-2.62; n = 3; I² = 32 %) for treatment duration of ≤3 days among women with a previous preterm delivery. Pooled OR for spontaneous abortion was 1.72 (95 % CI 1.40-2.12; n = 5; I2 = 72 %) and 1.15 (95 % CI 0.98-1.34; n = 12; I2 = 25 %) for major malformations. After exclusion of studies with critical risk of bias, pooled OR were 1.7 (1.42-2.04; n = 3; I2 = 19 %) and 1.13 (0.93-1.36; n = 9; I2 = 28 %) respectively. Among several specific malformations analyzed, only congenital hydrocephaly was significantly increased at 4.06 (95 % CI 1.75-9.42; n = 2; I² = 0%).

CONCLUSIONS

Data do not confirm the efficacy of metronidazole in reducing the risk of preterm birth and associated delivery outcomes. Further research is required to confirm the effect of high dose and short duration of metronidazole treatment on preterm birth among the high-risk group. Regarding the increased odds of spontaneous abortion, RCTs are required to assess the role of the underlying infection. The need for further studies to confirm the risk of congenital hydrocephaly is paramount.

Landscape of Preterm Birth Therapeutics and a Path Forward

Preterm birth (PTB) remains the leading cause of infant morbidity and mortality. Despite 50 years of research, therapeutic options are limited and many lack clear efficacy. Tocolytic agents are drugs that briefly delay PTB, typically to allow antenatal corticosteroid administration for accelerating fetal lung maturity or to transfer patients to high-level care facilities. Globally, there is an unmet need for better tocolytic agents, particularly in low- and middle-income countries. Although most tocolytics, such as betamimetics and indomethacin, suppress downstream mediators of the parturition pathway, newer therapeutics are being designed to selectively target inflammatory checkpoints with the goal of providing broader and more effective tocolysis. However, the relatively small market for new PTB therapeutics and formidable regulatory hurdles have led to minimal pharmaceutical interest and a stagnant drug pipeline. In this review, we present the current landscape of PTB therapeutics, assessing the history of drug development, mechanisms of action, adverse effects, and the updated literature on drug efficacy. We also review the regulatory hurdles and other obstacles impairing novel tocolytic development. Ultimately, we present possible steps to expedite drug development and meet the growing need for effective preterm birth therapeutics.

Chlamydia trachomatis Screening and Treatment in Pregnancy to Reduce Adverse Pregnancy and Neonatal Outcomes: A Review

Chlamydial trachomatis infection has been associated with adverse pregnancy and neonatal outcomes such as premature rupture of membranes, preterm birth, low birth weight, conjunctivitis, and pneumonia in infants. This review evaluates existing literature to determine potential benefits of antenatal screening and treatment of C. trachomatis in preventing adverse outcomes. A literature search revealed 1824 studies with 156 full-text articles reviewed. Fifteen studies were selected after fulfilling inclusion criteria. Eight studies focused on chlamydial screening and treatment to prevent adverse pregnancy outcomes such as premature rupture of membranes, preterm birth, low birth weight, growth restriction leading to small for gestational age infants, and neonatal death. Seven studies focused on the effects of chlamydial screening and treatment on adverse infant outcomes such as chlamydial infection including positive mucosal cultures, pneumonia, and conjunctivitis. Given the heterogeneity of those studies, this focused review was exclusively qualitative in nature. When viewed collectively, 13 of 15 studies provided some degree of support that antenatal chlamydial screening and treatment interventions may lead to decreased adverse pregnancy and infant outcomes. However, notable limitations of these individual studies also highlight the need for further, updated research in this area, particularly from low and middle-income settings.

Maternal Depressive Symptoms, Sleep, and Odds of Spontaneous Early Birth: Implications for Racial Inequities in Birth Outcomes

STUDY OBJECTIVES

Delivery prior to full term affects 37% of US births, including ~400,000 preterm births (<37 weeks) and >1,000,000 early term births (37-38 weeks). Approximately 70% of cases of shortened gestation are spontaneous - without medically-indicated cause. Elucidation of modifiable behavioral factors would have considerable clinical impact.

METHODS

This study examined the role of depressive symptoms and sleep quality in predicting the odds of spontaneous shortened gestation among 317 women (135 Black, 182 White) who completed psychosocial assessment in mid-pregnancy.

RESULTS

Adjusting for key covariates, Black women had 1.89 times higher odds of spontaneous shortened gestation compared to White women (OR (95% CI) = 1.89 (1.01, 3.53), p=0.046). Women who reported only poor subjective sleep quality (PSQI > 6) or only elevated depressive symptoms (CES-D ≥ 16) exhibited no statistically significant differences in odds of spontaneous shortened gestation compared to those with neither risk factor. However, women with comorbid poor sleep and depressive symptoms exhibited markedly higher odds of spontaneous shortened gestation than those with neither risk factor [39.2% versus 15.7%, [OR (95% CI) = 2.69 (1.27, 5.70), p = 0.01]. A higher proportion of Black women met criteria for both risk factors (23% of Black women versus 11% of White women; p=0.004), with a lower proportion experiencing neither risk factor (40.7% of Black versus 64.3% of White women; p < 0.001).

CONCLUSIONS

Additive effects of poor subjective sleep quality and depressive symptoms were observed with markedly higher odds of spontaneous shortened gestation among women with both risk factors. Racial inequities in rates of comorbid exposure corresponded with inequities in shortened gestation. Future empirical studies and intervention efforts should consider the interactive effects of these commonly co-morbid exposures.

Timing of Cervico-Vaginal Cytokine Collection during Pregnancy and Preterm Birth: A Comparative Analysis in the PRINCESA Cohort

Preterm birth (PTB), defined as birth before 37 completed weeks of gestation, is a major cause of infant morbidity and mortality. Inflammation is an important component in the physiopathologic pathway leading to PTB but results from cross-sectional studies on associations between inflammation, as measured by cytokines, and PTB are inconsistent. Timing of cytokine measurement during pregnancy varies between studies and may contribute to inconsistent findings. We investigated the effects of timing on associations between 16 cervico-vaginal cytokines (Eotaxin, IL-10, IL-12p40, IL-17, IL-1RA, sIL-2rα, IL-1a, IL-1β, IL-2, IL-6, IP-10, MCP-1, MIP-1α, MIP-1β, TNFα, and VEGF) and PTB among 90 women throughout pregnancy. We used logistic regression to compare associations between concentrations of cervico-vaginal cytokines from periods in pregnancy and PTB. Trimester 1 cytokines had the strongest positive associations with PTB; for example, OR = 1.76 (95% confidence interval: 1.28, 2.42) for IL-6. Second and third trimester associations were weaker but largely positive. IL-1α was the only cytokine with a negative association (trimesters 2, 3 and overall pregnancy). Strong first trimester associations between cytokines and PTB suggest that measuring cytokines early in pregnancy may hold promise for early identification of PTB risk. Variations in cytokine measurement during pregnancy may contribute to inconsistencies among studies.

Skewed logit model for analyzing correlated infant morbidity data

BACKGROUND

Infant morbidity is a topic of interest because it is used globally as an indicator of the status of health care in a country. A large body of evidence supports an association between bacterial vaginosis (BV) and infant morbidity. When estimating the relationship between the predictors and the estimated variable of morbidity severity, the latter exhibits imbalanced data, which means that violation of symmetry is expected. Two competing methods of analysis, that is, (1) probit and (2) logit techniques, can be considered in this context and have been applied to model such outcomes. However, these models may yield inconsistent results. While non-normal modeling approaches have been embraced in the recent past, the skewed logit model has been given little attention. In this study, we exemplify its usefulness in analyzing imbalanced longitudinal responses data.

METHODOLOGY

While numerous non-normal methods for modeling binomial responses are well established, there is a need for comparison studies to assess their usefulness in different scenarios, especially under a longitudinal setting. This is addressed in this study. We use a dataset from Kenya about infants born to human immunodeficiency virus (HIV) positive mothers, who are also screened for BV. We aimed to investigate the effect of BV on infant morbidity across time. We derived a score for morbidity incidences depending on illnesses reported during the month of reference. By adjusting for the mother's BV status, the child's HIV status, sex, feeding status, and weight for age, we estimated the standard binary logit and skewed logit models, both using Generalized Estimating Equations.

RESULTS

Results show that accounting for skewness in imbalanced binary data can show associations between variables in line with expectations documented by the literature. In addition, an in-depth analysis accounting for skewness has shown that, over time, maternal BV is associated with multiple health conditions in infants.

INTERPRETATION

Maternal BV status was positively associated with infant morbidity incidences, which highlights the need for early intervention in cases of HIV-infected pregnant women.

Stillbirth and fetal anomalies: secondary analysis of a case-control study

OBJECTIVE

Approximately 10% of stillbirths are attributed to fetal anomalies, but anomalies are also common in live births. We aimed to assess the relationship between anomalies, by system and stillbirth.

DESIGN

Secondary analysis of a prospective, case-control study.

SETTING

Multicentre, 59 hospitals in five regional catchment areas in the USA.

POPULATION OR SAMPLE

All stillbirths and representative live birth controls.

METHODS

Standardised postmortem examinations performed in stillbirths, medical record abstraction for stillbirths and live births.

MAIN OUTCOME MEASURES

Incidence of major anomalies, by type, compared between stillbirths and live births with univariable and multivariable analyses using weighted analysis to account for study design and differential consent.

RESULTS

Of 465 singleton stillbirths included, 23.4% had one or more major anomalies compared with 4.3% of 1871 live births. Having an anomaly increased the odds of stillbirth; an increasing number of anomalies was more highly associated with stillbirth. Regardless of organ system affected, the presence of an anomaly increased the odds of stillbirth. These relationships remained significant if stillbirths with known genetic abnormalities were excluded. After multivariable analyses, the adjusted odds ratio (aOR) of stillbirth for any anomaly was 4.33 (95% CI 2.80-6.70) and the systems most strongly associated with stillbirth were cystic hygroma (aOR 29.97, 95% CI 5.85-153.57), and thoracic (aOR16.18, 95% CI 4.30-60.94) and craniofacial (aOR 35.25, 95% CI 9.22-134.68) systems.

CONCLUSIONS

In pregnancies affected by anomalies, the odds of stillbirth are higher with increasing numbers of anomalies. Anomalies of nearly any organ system increased the odds of stillbirth even when adjusting for gestational age and maternal race.

TWEETABLE ABSTRACT

Stillbirth risk increases with anomalies of nearly any organ system and with number of anomalies seen.

Asymptomatic Bacterial Vaginosis: To Treat or Not to Treat?

Purpose of Review

The purpose of this review is to summarize current evidence for and against the treatment of asymptomatic bacterial vaginosis (BV) in women.

Recent Findings

Asymptomatic BV is common although its pathogenesis remains incompletely understood. In favor of treating asymptomatic BV is the large body of data supporting that it is sexually transmitted. Along these lines and similar to other STIs, treatment of BV, regardless of symptom status, should be considered to reduce adverse outcomes of infection (i.e. adverse birth outcomes, infertility, post-gynecologic surgery infections, etc.) and prevent further sexual transmission of BV pathogen(s) to sexual partners. One study has found that treatment of women with asymptomatic BV led to a significant reduction in incident chlamydial infections over a 6 month follow-up period, compared to observation-only women. Additionally, some women with asymptomatic BV actually have symptomatic BV but do not recognize these symptoms as an infection. Nevertheless, limitations of the trial regarding treatment of asymptomatic BV as well as the 2020 United States Preventative Task Force recommendation against screening and treatment of asymptomatic BV in pregnant women dampen enthusiasm for recommending treatment in this setting.

Summary

Treatment of asymptomatic BV remains controversial. Additional studies are needed to further investigate the pathogenesis of BV, which will directly influence advances in its diagnosis, treatment, and prevention.

Choosing the left fork: Steven Offenbacher and understanding maternal periodontal disease and adverse pregnancy outcomes

Steven Offenbacher was one of the first researchers to identify periodontal disease as a risk factor for various adverse pregnancy outcomes. Cohort and case-controlled studies of pregnant women have demonstrated periodontal disease as a risk factor for preterm birth, preeclampsia, and fetal growth restriction. Periodontal therapy during the second trimester improves maternal oral health but fails to reduce the risk of preterm birth. A possible association between periodontal disease and gestational diabetes has also been reported. In one model, periodontal bacteria gain access to the systemic circulation, and thereby the placenta, resulting in local inflammation, placental dysfunction, and, consequently, adverse pregnancy outcomes. It is crucial to increase awareness of the links between maternal periodontal and adverse pregnancy outcomes and to promote oral health prophylaxis during pregnancy.

Sleep disturbances and inflammatory gene expression among pregnant women: Differential responses by race

Excessive inflammation in pregnancy predicts adverse birth outcomes, including shortened gestational length and lower birthweight, with African American women at greater risk. As substantial racial disparities in sleep quality, and evidence that African Americans have increased vulnerability for sleep-induced inflammatory dysregulation, sleep may be a critical, modifiable health behavior that contributes to racial disparities in birth outcomes. The present study examined sleep disturbance as a predictor of genome-wide transcriptome profiles of peripheral blood samples from 103 pregnant women (33 African American, 70 white) assessed at 18.7 ± 7.2 weeks gestation. We hypothesized that pregnant women with significant sleep disturbances would have gene expression profiles indicating over-expression of inflammatory pathways, with greater effects among African American compared to white women. Promoter-based bioinformatics analyses of differentially expressed genes indicated greater activation of NF-кB, AP1, and CREB transcription factors among African American women with sleep disturbances (all p < 0.05), and enhanced activation of AP1, but not NF-кB and reduced CREB activity among white women with sleep disturbances (p < 0.05). Differences in glucocorticoid receptor (GR) activity were also observed, in which African American women with sleep disturbances had reduced GR activity (p < 0.05), but white women with sleep disturbances showed a trend for enhanced GR activity (p = 0.11). Similarly, Interferon Response Factor (IRF) activity was reduced in African American women while increased in white women with sleep disturbances (p < 0.05). The current study provides novel evidence for gene expression related to inflammation, glucocorticoids, and anti-viral immunity among pregnant women with sleep disturbances, with differential effects by race. African Americans showed greater breadth and magnitude in these proinflammatory and anti-viral pathways than whites, with divergence in anti-inflammatory glucocorticoid, proinflammatory adrenergic-mediated cAMP, and anti-viral interferon responses. These data elucidate the role of sleep disturbances in intracellular inflammatory and anti-viral immunity in pregnancy and provide a potential target for intervention.

A Randomized Controlled Open Label Crossover Trial to Study Vaginal Colonization of Orally Administered Lactobacillus Reuteri RC-14 and Rhamnosus GR-1 in Pregnant Women at High Risk for Preterm Labor

Lactobacilli administration has been suggested for the treatment and prevention of bacterial vaginosis, which increases the risk for preterm birth. We aimed to evaluate the vaginal colonization of lactobacilli orally administered to pregnant women at risk for preterm birth. We performed a randomized and controlled crossover study between January 2016 and May 2017. Forty pregnant women at high risk for preterm birth with normal vaginal flora (Nugent score ≤ 3) were randomized to either receive two oral capsules/day each containing 5 × 10⁹Lactobacilli (L.) rhamnosus GR-1 and L. reuteri RC-14 (n = 20) or no treatment (n = 20) for 2 months. Treatments were then crossed over for an additional two months. A vaginal examination and swabbing were performed for assessment of bacterial vaginosis at baseline and every month until study completion. At the same time points, vaginal samples were cultured and subjected to matrix-assisted-laser-desorption/ionization-time-of-flight-mass-spectrometry (MALDI TOF-MS) for the detection of the specific bacterial strains contained in the capsules. The primary endpoint was the presence of the administered lactobacilli strains in the vagina during the first two months of follow-up. Thirty-eight women completed the study. During the first two months of treatment, L. rhamnosus GR-1 was detected in one (5%) woman on the probiotic treatment and 2 (11%) women receiving no treatment (p = 0.6). L. rhamnosus GR-1 was detected in vaginal samples of 4 (11%) women during probiotic treatment (of both groups) and L. reuteri RC-14 was not detected in any samples. The rest of the endpoints were not different between the groups. Altogether, vaginal colonization of lactobacilli following oral administration is low during pregnancy.

Screening for Bacterial Vaginosis in Pregnant Persons to Prevent Preterm Delivery: US Preventive Services Task Force Recommendation Statement

IMPORTANCE

Bacterial vaginosis is common and is caused by a disruption of the microbiological environment in the lower genital tract. In the US, reported prevalence of bacterial vaginosis among pregnant women ranges from 5.8% to 19.3% and is higher in some races/ethnicities. Bacterial vaginosis during pregnancy has been associated with adverse obstetrical outcomes including preterm delivery, early miscarriage, postpartum endometritis, and low birth weight.

OBJECTIVE

To update its 2008 recommendation, the USPSTF commissioned a review of the evidence on the accuracy of screening and the benefits and harms of screening for and treatment of bacterial vaginosis in asymptomatic pregnant persons to prevent preterm delivery.

POPULATION

This recommendation applies to pregnant persons without symptoms of bacterial vaginosis.

EVIDENCE ASSESSMENT

The USPSTF concludes with moderate certainty that screening for asymptomatic bacterial vaginosis in pregnant persons not at increased risk for preterm delivery has no net benefit in preventing preterm delivery. The USPSTF concludes that for pregnant persons at increased risk for preterm delivery, the evidence is conflicting and insufficient, and the balance of benefits and harms cannot be determined.

CONCLUSIONS AND RECOMMENDATION

The USPSTF recommends against screening for bacterial vaginosis in pregnant persons not at increased risk for preterm delivery. (D recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for bacterial vaginosis in pregnant persons at increased risk for preterm delivery. (I statement).

Screening for Bacterial Vaginosis in Pregnant Adolescents and Women to Prevent Preterm Delivery: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Preterm delivery results in adverse outcomes; identifying and treating bacterial vaginosis may reduce its occurrence.

OBJECTIVE

To update the evidence on screening and treatment of asymptomatic bacterial vaginosis in pregnancy for the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, Cochrane Library, and trial registries through May 29, 2019; bibliographies from retrieved articles, experts, and surveillance of the literature through December 31, 2019.

STUDY SELECTION

Fair- or good-quality English-language studies evaluating diagnostic accuracy of tests feasible within primary care; randomized clinical trials (RCTs); nonrandomized controlled intervention studies (for harms only); or meta-analyses of metronidazole or clindamycin.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently assessed titles/abstracts and full-text articles, extracted data, and assessed study quality; when at least 3 similar studies were available, meta-analyses were conducted.

MAIN OUTCOMES AND MEASURES

Sensitivity, specificity, preterm delivery, maternal adverse effects, congenital birth defects, childhood cancer.

RESULTS

Forty-four studies (48 publications) were included. No studies evaluated the benefits or harms of screening. Twenty-five studies (n = 15 785) evaluated the accuracy of screening tests; across individual studies and tests, sensitivity ranged from 0.36 to 1.0 and specificity ranged from 0.49 to 1.0. Among trials reporting findings from general obstetric populations (n = 7953), no significant association was observed between treatment and spontaneous delivery before 37 weeks (pooled absolute risk difference [ARD], -1.44% [95% CI, -3.31% to 0.43%]; 8 RCTs, n = 7571) or any delivery before 37 weeks (pooled ARD, 0.20% [95% CI, -1.13% to 1.53%]; 6 RCTs, n = 6307). Among 5 trials reporting findings among women with a prior preterm delivery, findings were inconsistent; 3 showed a significant beneficial effect, while 2 did not. Maternal adverse events from treatment were infrequent and minor (eg, candidiasis) but were slightly more common with active treatment compared with placebo across 8 RCTs. Two meta-analyses of observational studies reported no significant association between metronidazole exposure and congenital malformations (odds ratio, 0.96 [95% CI, 0.75 to 1.22]; odds ratio, 1.08 [95% CI, 0.90 to 1.29]). One cohort study reported no significantly increased incidence of childhood cancer among metronidazole-exposed children (adjusted relative risk, 0.81 [95% CI, 0.41 to 1.59]). However, studies of in utero exposure had important limitations.

CONCLUSIONS AND RELEVANCE

Accuracy of screening tests for bacterial vaginosis varies. The evidence suggests no difference in the incidence of preterm delivery and related outcomes from treatment for asymptomatic bacterial vaginosis in a general obstetric population but was inconclusive for women with a prior preterm delivery. Maternal adverse events from treatment appear to be infrequent and minor, but the evidence about harms from in utero exposure was inconclusive.

Protective effect of high zinc levels on preterm birth induced by mercury exposure during pregnancy: A birth cohort study in China

OBJECTIVE

The aims of our study were to determine whether prenatal mercury levels are associated with the risk of preterm birth (PTB) and whether high maternal serum zinc (Zn) levels alleviate any negative effects of maternal mercury (Hg) exposure regarding PTB.

METHODS

Serum concentrations of Zn and Hg were measured in 3025 pregnant women from the Ma'anshan Birth Cohort. Before the collection of blood samples, they underwent examinations via the completion of questionnaires. The delivery records of the women were obtained from a series of medical records. We divided the study population into tertiles according to the participants' Hg levels: the low-Hg group (the first tertile, <0.30 μg/L), the medium-Hg group (the second tertile, 0.30-0.43 μg/L) and the high-Hg group (the third tertile, ≥0.43 μg/L). The associations of Hg exposure with both the risk of PTB and gestational age (weeks) at birth were estimated using a binary logistic regression model and multivariable linear regression analysis, respectively. Afterwards, we conducted a repeated analyses test after the participants were stratified according to their Zn levels, using the 75th percentile division method.

RESULTS

Overall, the medians and the interquartile ranges of Hg and Zn in the second trimester were 0.36 (0.27, 0.48) μg/L and 812.34 (731.26, 896.59) μg/L, respectively. Hg levels were associated with PTB [adjusted odds ratio (OR) and 95% confidence interval (95% CI): 1.91 (1.17, 3.12) for the third tertile vs. the first tertile of the serum Hg levels]. In the stratification analysis of the participants in the low-Zn group, the high-Hg group exhibited a significant odds ratio of PTB [adjusted OR (95% CI): 1.87 (1.08, 3.24)], compared to the low-Hg group. However, in the participants from the high-Zn group, the high-Hg group exhibited a non-significant OR of PTB [adjusted OR (95% CI): 2.32 (0.73, 7.42)]. In the multivariate linear regression analysis, gestational age (weeks) at delivery was significantly and inversely associated with the ln-transformed Hg concentrations [adjusted β (95% CI): -0.16 (-0.26, -0.06)]. Similarly, after the stratification analysis in the high-Zn group, there were no significant associations between PTB and the Hg levels [adjusted β (95% CI): -0.12 (-0.33, 0.09)].

CONCLUSION

Prenatal Hg exposure adversely affected PTB, and high Zn levels alleviate this effect, which indicates that a more stringent control of Hg and a sufficient intake of Zn are necessary to help birth outcomes.

Prenatal phthalate exposure in relation to gestational age and preterm birth in a prospective cohort study

This study enrolled 3266 pregnant women, to explore the relationship of prenatal phthalate exposure with the risk of preterm birth and gestational age. All participants filled questionnaires and provided with up to three urine samples during three trimesters. Seven phthalate metabolites in urines were measured. The incidences of very preterm, late preterm, early-term, late-term and postterm births were 0.58%, 3.52%, 24.22%, 10.53%, and 0.34%, respectively. Non-linear relationships were shown between phthalate metabolites and gestational age. Except for monomethyl phthalate (OR = 1.65, 95%CI = 1.17-2.34), the average concentrations of phthalate metabolites were associated with a slightly and insignificantly increased risk of overall preterm birth (<37⁺⁰ gestational weeks). Through a restricted cubic spline regression, phthalate metabolites were found to be related to the risk of overall preterm birth in a linear manner (p-value >0.05) or a non-linear manner (p-value <0.05). All curves indicated the overall preterm birth risk rose with the increase of phthalate metabolite concentrations. Finally, compared with full-term birth (39⁺⁰ to 40⁺⁶ gestational weeks), phthalate metabolites were associated with the elevated risks of very preterm, late preterm and postterm births, although some relationships were not statistically significant. In conclusion, these findings suggested non-linear associations between phthalate metabolites and gestational age. Exposure to some phthalate metabolites was associated with increased risks of overall preterm birth and postterm birth.

No. 211-Screening and Management of Bacterial Vaginosis in Pregnancy

OBJECTIVE

To review the evidence and provide recommendations on screening for and management of bacterial vaginosis in pregnancy.

OPTIONS

The clinical practice options considered in formulating the guideline.

OUTCOMES

Outcomes evaluated include antibiotic treatment efficacy and cure rates, and the influence of the treatment of bacterial vaginosis on the rates of adverse pregnancy outcomes such as preterm labour and delivery and preterm premature rupture of membranes.

EVIDENCE

Medline, EMBASE, CINAHL, and Cochrane databases were searched for articles, published in English before the end of June 2007 on the topic of bacterial vaginosis in pregnancy.

VALUES

The evidence obtained was rated using the criteria developed by the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Guideline implementation will assist the practitioner in developing an approach to the diagnosis and treatment of bacterial vaginosis in pregnant women. Patients will benefit from appropriate management of this condition.

VALIDATION

These guidelines have been prepared by the Infectious Diseases Committee of the SOGC, and approved by the Executive and Council of the SOGC.

SPONSORS

The Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

There is currently no consensus as to whether to screen for or treat bacterial vaginosis in the general pregnant population in order to prevent adverse outcomes, such as preterm birth.

Point-of-care testing and treatment of sexually transmitted infections to improve birth outcomes in high-burden, low-income settings: Study protocol for a cluster randomized crossover trial (the WANTAIM Trial, Papua New Guinea)

Background: Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and bacterial vaginosis have been associated with preterm birth and low birth weight, and are highly prevalent among pregnant women in many low- and middle-income settings. There is conflicting evidence on the potential benefits of screening and treating these infections in pregnancy. Newly available diagnostic technologies make it possible, for the first time, to conduct definitive field trials to fill this knowledge gap. The primary aim of this study is to evaluate whether antenatal point-of-care testing and immediate treatment of these curable sexually transmitted and genital infections (STIs) leads to reduction in preterm birth and low birth weight.

Methods: The Women and Newborn Trial of Antenatal Interventions and Management (WANTAIM) is a cluster-randomised crossover trial in Papua New Guinea to compare point-of-care STI testing and immediate treatment with standard antenatal care (which includes the WHO-endorsed STI ‘syndromic’ management strategy based on clinical features alone without laboratory confirmation). The unit of randomisation is a primary health care facility and its catchment communities. The primary outcome is a composite measure of two events: the proportion of women and their newborns in each trial arm, who experience either preterm birth (delivery <37 completed weeks of gestation as determined by ultrasound) and/or low birth weight (<2500 g measured within 72 hours of birth). The trial will also evaluate neonatal outcomes, as well as the cost-effectiveness, acceptability and health system requirements of this strategy, compared with standard care.

Conclusions: WANTAIM is the first randomised trial to evaluate the effectiveness, cost-effectiveness, acceptability and health system requirements of point-of-care STI testing and treatment to improve birth outcomes in high-burden settings. If the intervention is proven to have an impact, the trial will hasten access to these technologies and could improve maternal and neonatal health in high-burden settings worldwide.

Registration: ISRCTN37134032.

Point-of-care testing and treatment of sexually transmitted infections to improve birth outcomes in high-burden, low-income settings: Study protocol for a cluster randomized crossover trial (the WANTAIM Trial, Papua New Guinea)

Background: Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and bacterial vaginosis have been associated with preterm birth and low birth weight, and are highly prevalent among pregnant women in many low- and middle-income settings. There is conflicting evidence on the potential benefits of screening and treating these infections in pregnancy. Newly available diagnostic technologies make it possible, for the first time, to conduct definitive field trials to fill this knowledge gap. The primary aim of this study is to evaluate whether antenatal point-of-care testing and immediate treatment of these curable sexually transmitted and genital infections (STIs) leads to reduction in preterm birth and low birth weight. Methods: The Women and Newborn Trial of Antenatal Interventions and Management (WANTAIM) is a cluster-randomised crossover trial in Papua New Guinea to compare point-of-care STI testing and immediate treatment with standard antenatal care (which includes the WHO-endorsed STI 'syndromic' management strategy based on clinical features alone without laboratory confirmation). The unit of randomisation is a primary health care facility and its catchment communities. The primary outcome is a composite measure of two events: the proportion of women and their newborns in each trial arm, who experience either preterm birth (delivery <37 completed weeks of gestation as determined by ultrasound) and/or low birth weight (<2500 g measured within 72 hours of birth). The trial will also evaluate neonatal outcomes, as well as the cost-effectiveness, acceptability and health system requirements of this strategy, compared with standard care. Conclusions: WANTAIM is the first randomised trial to evaluate the effectiveness, cost-effectiveness, acceptability and health system requirements of point-of-care STI testing and treatment to improve birth outcomes in high-burden settings. If the intervention is proven to have an impact, the trial will hasten access to these technologies and could improve maternal and neonatal health in high-burden settings worldwide. Registration: ISRCTN37134032.