Antibiotic administration in patients with preterm premature rupture of membranes reduces the rate of histological chorioamnionitis: a prospective, randomized, controlled study

Latency Antibiotics in Preterm Prelabor Rupture of Membranes: A Comparison of Azithromycin Regimens

BACKGROUND

Treatment with antibiotics at the time of preterm prelabor rupture of membranes (PPROM) has been shown to prolong pregnancy. Due to the recurrent shortage of erythromycin, azithromycin has been substituted in the traditional regimen; however, there are little data on optimal dosing.

OBJECTIVE

The objective of this study was to determine whether there is a difference in latency from onset of PPROM to delivery in patients who received a single dose of azithromycin compared with a 5-day course.

METHODS

This was a single-center, multisite, retrospective, IRB approved analysis of patients admitted with a diagnosis of PPROM. Patients were included if rupture occurred between 22 0/7 and 33 6/7 weeks of gestation and received either a single dose or a 5-day course of azithromycin along with a beta lactam.

RESULTS

A total of 376 patients were reviewed with 296 patients included in the final analysis. There was no statistical difference in the primary outcome of latency days in patients who received the 5-day versus the single-dose course (4 vs 5 days, P = 0.641). There was a significantly higher rate of histologic chorioamnionitis in the single-dose course of azithromycin (46.4% vs 62.6%, P = 0.006).

CONCLUSIONS AND RELEVANCE

There was no difference in latency for patients who received a 5-day course of azithromycin versus a single dose for the treatment of PPROM. A higher rate of histologic chorioamnionitis was observed in those who received the single-day course. Prospective follow-up studies are needed to confirm these findings.

Clinical characteristics, complications, and predictive model of histological chorioamnionitis in women with preterm premature rupture of membranes

We aimed to analyze the impact of histological chorioamnionitis (HCA) in the presence of preterm premature rupture of the membranes (PPROM) on obstetric and neonatal outcomes, and its possible predictability. A retrospective cohort analysis of PPROM cases (20-37 weeks) was conducted comparing the patients with and without HCA, seeking a predictive model of HCA using logistic regression. A total of 295 cases of PPROM were selected, of which 72 (24.4%) had HCA. The group with HCA had a shorter latency period and a greater number of clinical and laboratory criteria in the evolution. The group with HCA had a worse comparative result and presented: lower gestational age at delivery, lower average birth weight, lower Apgar scores, longer neonatal hospitalization, worse maternal clinical conditions and, higher rates of stillbirth, low birth weight (LBW), very low birth weight (VLBW), complications in pregnancy and childbirth, and cesarean delivery due to fetal distress or chorioamnionitis. A predictive model for HCA was developed, with the following independent variables: abdominal pain (odds ratio [OR] = 11.61), uterine activity (noticeable contractions on physical exam) (OR = 5.97), fever (OR = 5.77), latency > 3 days (OR = 2.13), and C-reactive protein (OR = 1.01). With this model, an adequate receiver operating characteristic curve was found, with an area under the curve of 0.726, and some HCA probability curves were constructed for different clinical situations. In this novel study, we present a non-invasive predictive model, with clinical and laboratory variables, which may help in decision-making in a patient with PPROM.

Fetal-neonatal exposure to antibiotics and NEC development: A systematic review and meta-analysis

Background

Fetal and neonatal exposure to antibiotics may contribute to the development of necrotizing enterocolitis (NEC) in preterm infants. This systematic review and meta-analysis investigate whether exposure to third trimester maternal antibiotics (MAB) and/or prolongation of empirical antibiotics (PEAB) are associated with NEC development in preterms.

Method

We included observational and randomized controlled studies, including those on preterm or very low birth weight (VLBW) infants, from MEDLINE and EMBASE, published between 1990 and June 2021. Exposure was defined as third trimester MAB and/or PEAB. The two reviewers independently performed study selection, data extraction, and quality assessment.

Results

Three cohort studies compared third trimester MAB with no antibiotics. MAB was associated with lower NEC incidence, unadjusted pooled odds ratio (OR) is 0.57 (95% CI: 0.35-0.93). Twelve cohort studies showed that PEAB was associated with an increased risk of NEC. Ten observational cohort studies show an unadjusted OR of 2.72 (1.65-4.47), and two case-control studies show an unadjusted mean difference of 2.31 (0.94-3.68). Moderate to substantial heterogeneity was observed but decreased in studies with low risk of bias and large sample size.

Conclusion

Evidence suggests an association between MAB and decreased risk of NEC and an association between PEAB and increased risk of NEC. Further studies should confirm these associations and explore causality.

Systematic Review Registration

identifier [CRD42022304937].

Antibiotic prophylaxis in pregnant with premature rupture of ovular membranes: systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis of randomized clinical trials that compared the use of antibiotics versus placebo in premature rupture of membranes preterm and evaluated maternal, fetal and neonatal outcomes in pregnant women with premature rupture of ovular membranes at a gestational age between 24 and 37 weeks.

METHODS

A search was conducted using keywords in PubMed, Cochrane, Biblioteca Virtual em Saúde and Biblioteca Digital de Teses e Dissertações da USP between August 2018 and December 2021. A total of 926 articles were found. Those included were randomized clinical trials that compared the use of antibiotics versus placebo in the premature rupture of preterm membranes. Articles referring to antibiotics only for streptococcus agalactiae prophylaxis were excluded. The retrieved articles were independently and blindly analyzed by two reviewers. A total of 24 manuscripts met the inclusion criteria and 21 articles were included for quantitative analysis.

RESULTS

Among the maternal outcomes analyzed, there was a prolongation of the latency period that was ≥7 days. In addition, we observed a reduction in chorioamnionitis in the group of pregnant women who used antibiotics. As for endometritis and other maternal outcomes, there was no statistically significant difference between the groups. Regarding fetal outcomes, antibiotic prophylaxis worked as a protective factor for neonatal sepsis. Necrotizing enterocolitis and respiratory distress syndrome showed no statistically significant differences.

CONCLUSION

The study showed positive results in relation to antibiotic prophylaxis to prolong the latency period, new randomized clinical trials are needed to ensure its beneficial effect.

PROSPERO DATABASE REGISTRATION

(www.crd.york.ac.uk/prospero) under number CRD42020155315.

Developing a Core Outcome Set for the Evaluation of Antibiotic Use in Prelabor Rupture of Membranes: A Systematic Review and Semi-Structured Interview

Background: Prelabor rupture of membranes (PROM) is associated with maternal and neonatal infections. Although guidelines suggest prophylactic antibiotics for pregnant women with PROM, the optimal antibiotic regimen remains controversial. Synthesizing the data from different studies is challenging due to variations in reported outcomes. Objective: This study aimed to form the initial list of outcomes for the core outcome set (COS) that evaluates antibiotic use in PROM by identifying all existing outcomes and patients' views. Methods: Relevant studies were identified by searching PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang, and VIP databases. We also screened the references of the included studies as a supplementary search. We extracted basic information from the articles and the outcomes. Two reviewers independently selected the studies, extracted the data, extracted the outcomes, and grouped them into domains. Then, semi-structured interviews based on the potential factors collected by the systematic review were conducted at West China Second Hospital of Sichuan University. Pregnant women who met the diagnostic criteria for PROM were enrolled. Participants reported their concerns about the outcomes. Two researchers identified the pregnant women's concerns. Results: A total of 90 studies were enrolled in this systematic review. The median outcomes in the included studies was 7 (1-31), and 109 different unique outcomes were identified. Pre-term PROM (PPROM) had 97 outcomes, and term PROM (TPROM) had 70 outcomes. The classification and order of the core outcome domains of PPROM and TPROM were consistent. The physiological domain was the most common for PPROM and TPROM outcomes. Furthermore, 35.1 and 57.1% outcomes were only reported once in PPROM and TPROM studies, respectively. Thirty pregnant women participated in the semi-structured interviews; 10 outcomes were extracted after normalized, and the outcomes were reported in the systematic review. However, studies rarely reported pregnant women's concerns. Conclusion: There was considerable inconsistency in outcomes selection and reporting in studies about antibiotics in PROM. An initial core outcomes set for antibiotics in PROM was formed.

Prelabor Rupture of Membranes: ACOG Practice Bulletin, Number 217

Preterm birth occurs in approximately 10% of all births in the United States and is a major contributor to perinatal morbidity and mortality (). Prelabor rupture of membranes (PROM) that occurs preterm complicates approximately 2-3% of all pregnancies in the United States, representing a significant proportion of preterm births, whereas term PROM occurs in approximately 8% of pregnancies (). The optimal approach to assessment and treatment of women with term and preterm PROM remains challenging. Management decisions depend on gestational age and evaluation of the relative risks of delivery versus the risks (eg, infection, abruptio placentae, and umbilical cord accident) of expectant management when pregnancy is allowed to progress to a later gestational age. The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented. This Practice Bulletin is updated to include information about diagnosis of PROM, expectant management of PROM at term, and timing of delivery for patients with preterm PROM between 34 0/7 weeks of gestation and 36 6/7 weeks of gestation.

Effect on perinatal outcome of prophylactic antibiotics in preterm prelabor rupture of membranes: network meta-analysis of randomized controlled trials

OBJECTIVES

Prophylactic antibiotics are recommended routinely for preterm prelabor rupture of membranes (PPROM), but there is an abundance of potential treatments and a paucity of comparative information. The aims of this network meta-analysis were to compare the efficiency of different antibiotic regimens on perinatal outcomes and to assess the quality of the current evidence.

METHODS

This was a network meta-analysis of randomized controlled trials comparing prophylactic antibiotics, or regimens of antibiotics, with each other or with placebo/no treatment, in women with PPROM. MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, US Registry of Clinical Trials ( www.ClinicalTrials.gov) and gray literature sources were searched. The primary outcomes were neonatal mortality and chorioamnionitis; secondary outcomes included other measures of perinatal morbidity. Relative effect sizes were estimated using risk ratios (RR) and the relative ranking of the interventions was obtained using cumulative ranking curves. The quality of evidence for the primary outcomes was assessed according to GRADE guidelines, adapted for network meta-analysis.

RESULTS

The analysis included 20 studies (7169 participants randomized to 15 therapeutic regimens). For the outcome of chorioamnionitis, clindamycin + gentamycin (network RR, 0.19 (95% CI, 0.05-0.83)), penicillin (RR, 0.31 (95% CI, 0.16-0.6)), ampicillin/sulbactam + amoxicillin/clavulanic acid (RR, 0.32 (95% CI, 0.12-0.92)), ampicillin (RR, 0.52 (95% CI, 0.34-0.81)) and erythromycin + ampicillin + amoxicillin (RR, 0.71 (95% CI, 0.55-0.92)) were superior to placebo/no treatment. Erythromycin was the only effective drug for neonatal sepsis (RR, 0.74 (95% CI, 0.56-0.97)). Clindamycin + gentamycin (RR, 0.32 (95% CI, 0.11-0.89)) and erythromycin + ampicillin + amoxicillin (RR, 0.83 (95% CI, 0.69-0.99)) were the only effective regimens for respiratory distress syndrome, whereas ampicillin (RR, 0.42 (95% CI, 0.20-0.92)) and penicillin (RR, 0.49 (95% CI, 0.25-0.96)) were effective in reducing the rates of Grade-3/4 intraventricular hemorrhage. None of the antibiotics appeared significantly more effective than placebo/no treatment in reducing the rates of neonatal death, perinatal death and necrotizing enterocolitis. No network RR could be estimated for neonatal intensive care unit admission. The overall quality of the evidence, according to GRADE guidelines, was moderate to very low, depending on the outcome and comparison.

CONCLUSIONS

Several antibiotics appear to be more effective than placebo/no treatment in reducing the rate of chorioamnionitis after PPROM. However, none of them is clearly and consistently superior compared to other antibiotics, and most are not superior to placebo/no treatment for other outcomes. The overall quality of the evidence is low and needs to be updated, as microbial resistance may have emerged for some antibiotics, while others are underrepresented in the existing evidence. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The Effect of Non-penicillin Antibiotic Regimens on Neonatal Outcomes in Preterm Premature Rupture of Membranes

Objective  A 7-day course of a penicillin (PCN) and macrolide is standard of care (SAR) in preterm premature rupture of membranes (PPROM). Data regarding alternative antibiotic regimens are limited. We sought to assess the impact of non-PCN regimens on neonatal outcomes. Study Design  Secondary analysis of randomized controlled trial of antenatal magnesium sulfate. Singleton, nonanomalous pregnancies complicated by PPROM at > 24 weeks of gestation receiving the SAR were compared with women receiving a non- β -lactam regimen and a macrolide (NPCR). Primary outcome was a neonatal composite. Secondary outcomes included pregnancy latency, endometritis, and chorioamnionitis. Results  A total of 949 women met inclusion criteria; 821(56%) received the SAR and 128(8.8%) received NPCR. Adjusted models did not demonstrate worse outcomes (AOR [adjusted odds ratio] = 0.50; 95% CI [confidence interval]: 0.22-1.11). Neonates receiving SAR were less likely to have bronchopulmonary dysplasia (BPD; p  = 0.03) but more likely to have severe necrotizing enterocolitis (sNEC; p  = 0.04). Risk for chorioamnionitis and median latency did not differ between groups but women receiving the SAR were less likely to get endometritis (AOR = 0.35; 95% CI: 0.14-0.91). Conclusions  In this cohort, receiving NPCR in the setting of PPROM did not impact the overall risk of adverse neonatal outcomes or latency, but did increase the risk of endometritis. Alterations in individual neonatal morbidities suggest follow-up studies are needed.

[Antibiotic prophylaxis in preterm premature rupture of membranes: CNGOF preterm premature rupture of membranes guidelines]

OBJECTIVE

To analyse benefits and risks of antibiotic prophylaxis in the management of preterm premature rupture of membranes.

METHODS

PubMed and Cochrane Central databases search.

RESULTS

Streptoccoccus agalactiae (group B streptococcus) and Escherichia coli are the two main bacteria identified in early neonatal sepsis (EL3). Antibiotic prophylaxis at admission is associated with significant prolongation of pregnancy (EL2), reduction in neonatal morbidity (EL1) without impact on neonatal mortality (EL2). Co-amoxiclav could be associated with an increased risk for neonatal necrotising enterocolitis (EL2). Antibiotic prophylaxis at admission in women with preterm premature rupture of the membranes is recommended (Grade A). Monotherapy with amoxicillin, third generation cephalosporin and erythromycin can be used as well as combination of erythromycin and amoxicillin (Professional consensus) for 7 days (GradeC). Shorter treatment is possible when initial vaginal culture is negative (Professional consensus). Co-amxiclav, aminoglycosides, glycopeptides, first and second generation cephalosporin, clindamycin and metronidazole are not recommended (Professional consensus).

CONCLUSIONS

Antibiotic prophylaxis against Streptoccoccus agalactiae (group B streptococcus) and E. coli is recommended in women with preterm premature of the membranes (Grade A). Monotherapy with amoxicillin, third generation cephalosporin or erythromycin, as well as combination of erythromycin and amoxicillin are recommended (Professional consensus).

ACOG Practice Bulletin No. 188: Prelabor Rupture of Membranes

Preterm delivery occurs in approximately 12% of all births in the United States and is a major factor that contributes to perinatal morbidity and mortality (1, 2). Preterm prelabor rupture of membranes (also referred to as premature rupture of membranes) (PROM) complicates approximately 3% of all pregnancies in the United States (3). The optimal approach to clinical assessment and treatment of women with term and preterm PROM remains controversial. Management hinges on knowledge of gestational age and evaluation of the relative risks of delivery versus the risks of expectant management (eg, infection, abruptio placentae, and umbilical cord accident). The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented.

Practice Bulletin No. 172: Premature Rupture of Membranes

Preterm delivery occurs in approximately 12% of all births in the United States and is a major factor that contributes to perinatal morbidity and mortality (1, 2). Preterm premature rupture of membranes (PROM) complicates approximately 3% of all pregnancies in the United States (3). The optimal approach to clinical assessment and treatment of women with term and preterm PROM remains controversial. Management hinges on knowledge of gestational age and evaluation of the relative risks of delivery versus the risks of expectant management (eg, infection, abruptio placentae, and umbilical cord accident). The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented.

Non-Invasive Prediction of Histologic Chorioamnionitis in Women with Preterm Premature Rupture of Membranes

PURPOSE

To develop a model based on non-invasive clinical and ultrasonographic parameters for predicting the likelihood of subsequent histologic chorioamnionitis in women with preterm premature rupture of membranes (PPROM) and to determine whether the inclusion of invasive test results improves the predictive value of the model.

MATERIALS AND METHODS

This retrospective cohort study included 146 consecutive women presenting with PPROM (20-33 weeks). Transvaginal ultrasonographic assessment of cervical length was performed. Maternal serum C-reactive protein (CRP) levels and white blood cell (WBC) counts were measured after amniocentesis. Amniotic fluid (AF) obtained by amniocentesis was cultured, and interleukin-6 (IL-6) levels and WBC counts were determined. The primary outcome measure was histologic chorioamnionitis.

RESULTS

Risk scores based on serum CRP concentrations and gestational age (model 1) were calculated for each patient. The model was shown to have adequate goodness of fit and an area under the receiver operating characteristic curve (AUC) of 0.742. When including AF test results (e.g., AF IL-6 levels) in model 1, serum CRP concentrations were found to be insignificant, and thus, were excluded from model 2, comprising AF IL-6 levels and gestational age. No significant difference in AUC was found between models 1 and 2.

CONCLUSION

For women with PPROM, the newly developed model incorporating non-invasive parameters (serum CRP and gestational age) was moderately predictive of histologic chorioamnionitis. The inclusion of invasive test results added no predictive information to the model in this setting.

Sterile and microbial-associated intra-amniotic inflammation in preterm prelabor rupture of membranes

OBJECTIVE

The objectives of this study were to: (1) determine the amniotic fluid (AF) microbiology of patients with preterm prelabor rupture of membranes (PROM); and (2) examine the relationship between intra-amniotic inflammation with and without microorganisms (sterile inflammation) and adverse pregnancy outcomes in patients with preterm PROM.

METHODS

AF samples obtained from 59 women with preterm PROM were analyzed using cultivation techniques (for aerobic and anaerobic bacteria as well as genital mycoplasmas) and with broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS). AF concentration of interleukin-6 (IL-6) was determined using ELISA. Results of both tests were correlated with AF IL-6 concentrations and the occurrence of adverse obstetrical/perinatal outcomes.

RESULTS

(1) PCR/ESI-MS, AF culture, and the combination of these two tests each identified microorganisms in 36% (21/59), 24% (14/59) and 41% (24/59) of women with preterm PROM, respectively; (2) the most frequent microorganisms found in the amniotic cavity were Sneathia species and Ureaplasma urealyticum; (3) the frequency of microbial-associated and sterile intra-amniotic inflammation was overall similar [ 29% (17/59)]: however, the prevalence of each differed according to the gestational age when PROM occurred; (4) the earlier the gestational age at preterm PROM, the higher the frequency of both microbial-associated and sterile intra-amniotic inflammation; (5) the intensity of the intra-amniotic inflammatory response against microorganisms is stronger when preterm PROM occurs early in pregnancy; and (6) the frequency of acute placental inflammation (histologic chorioamnionitis and/or funisitis) was significantly higher in patients with microbial-associated intra-amniotic inflammation than in those without intra-amniotic inflammation [93.3% (14/15) versus 38% (6/16); p = 0.001].

CONCLUSIONS

(1) The frequency of microorganisms in preterm PROM is 40% using both cultivation techniques and PCR/ESI-MS; (2) PCR/ESI-MS identified microorganisms in the AF of 50% more women with preterm PROM than AF culture; and (3) sterile intra-amniotic inflammation was present in 29% of these patients, and it was as or more common than microbial-associated intra-amniotic inflammation among those presenting after, but not before, 24 weeks of gestation.

A retrospective comparison of antibiotic regimens for preterm premature rupture of membranes

OBJECTIVE

To evaluate whether the use of ampicillin and azithromycin leads to a similar latency period in preterm premature rupture of membranes as ampicillin and erythromycin and whether the substitution of azithromycin for erythromycin effects rates of other outcomes.

METHODS

We performed a retrospective cohort study of women with preterm premature rupture of membranes between 24 and 34 completed weeks of gestation and compared two groups: those who received ampicillin and erythromycin and those who received ampicillin and azithromycin. Primary outcome was length of latency (defined as time from first antibiotic dose to delivery) and secondary outcomes were rates of chorioamnionitis, cesarean delivery, Apgar scores, birth weight, neonatal death, neonatal sepsis, and neonatal respiratory distress syndrome.

RESULTS

Of 168 women who met inclusion criteria, 75 received ampicillin and erythromycin and 93 received ampicillin and azithromycin. There was no difference in latency between groups: 9.6±13.2 days (erythromycin) compared with 9.4±10.0 (azithromycin) days (P=.40). Secondary outcomes did not differ between groups. We had 80% power to detect a difference of 5 days.

CONCLUSION

Among women with preterm premature rupture of membranes between 24 and 34 completed weeks of gestation, substitution of azithromycin for erythromycin in the recommended antibiotic regimen did not affect latency or any other measured maternal or fetal outcomes.

LEVEL OF EVIDENCE

III.

Antibiotics for preterm rupture of membranes

BACKGROUND

Premature birth carries substantial neonatal morbidity and mortality. Subclinical infection is associated with preterm rupture of membranes (PROM). Prophylactic maternal antibiotic therapy might lessen infectious morbidity and delay labour, but could suppress labour without treating underlying infection.

OBJECTIVES

To evaluate the immediate and long-term effects of administering antibiotics to women with PROM before 37 weeks, on maternal infectious morbidity, neonatal morbidity and mortality, and longer-term childhood development.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2013).

SELECTION CRITERIA

Randomised controlled trials comparing antibiotic administration with placebo that reported clinically relevant outcomes were included as were trials of different antibiotics. Trials in which no placebo was used were included for the outcome of perinatal death alone.

DATA COLLECTION AND ANALYSIS

We extracted data from each report without blinding of either the results or the treatments that women received. We sought unpublished data from a number of authors.

MAIN RESULTS

We included 22 trials, involving 6872 women and babies.The use of antibiotics following PROM is associated with statistically significant reductions in chorioamnionitis (average risk ratio (RR) 0.66, 95% confidence interval (CI) 0.46 to 0.96, and a reduction in the numbers of babies born within 48 hours (average RR 0.71, 95% CI 0.58 to 0.87) and seven days of randomisation (average RR 0.79, 95% CI 0.71 to 0.89). The following markers of neonatal morbidity were reduced: neonatal infection (RR 0.67, 95% CI 0.52 to 0.85), use of surfactant (RR 0.83, 95% CI 0.72 to 0.96), oxygen therapy (RR 0.88, 95% CI 0.81 to 0.96), and abnormal cerebral ultrasound scan prior to discharge from hospital (RR 0.81, 95% CI 0.68 to 0.98). Co-amoxiclav was associated with an increased risk of neonatal necrotising enterocolitis (RR 4.72, 95% CI 1.57 to 14.23).One study evaluated the children's health at seven years of age (ORACLE Children Study) and found antibiotics seemed to have little effect on the health of children.

AUTHORS' CONCLUSIONS

Routine prescription of antibiotics for women with preterm rupture of the membranes is associated with prolongation of pregnancy and improvements in a number of short-term neonatal morbidities, but no significant reduction in perinatal mortality. Despite lack of evidence of longer-term benefit in childhood, the advantages on short-term morbidities are such that we would recommend antibiotics are routinely prescribed. The antibiotic of choice is not clear but co-amoxiclav should be avoided in women due to increased risk of neonatal necrotising enterocolitis.

Practice bulletins No. 139: premature rupture of membranes

Preterm delivery occurs in approximately 12% of all births in the United States and is a major factor that contributes to perinatal morbidity and mortality (). Preterm premature rupture of membranes (PROM) complicates approximately 3% of all pregnancies in the United States (). The optimal approach to clinical assessment and treatment of women with term and preterm PROM remains controversial. Management hinges on knowledge of gestational age and evaluation of the relative risks of delivery versus the risks of expectant management (eg, infection, abruptio placentae, and umbilical cord accident). The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented.

Characteristics of early-onset neonatal sepsis caused by Escherichia coli

OBJECTIVE

This study was conducted to document the perinatal risk factors associated with early-onset neonatal Escherichia coli sepsis and adverse neonatal outcomes.

MATERIALS AND METHODS

A case-control study of early-onset E coli sepsis compared with that of non-E coli sepsis was conducted by a retrospective data review of all infants with a diagnosis of sepsis during the first 7 days of life from the pediatric unit of Mackay Memorial Hospital from January 2004 to October 2008. After adjustment for gestational age, each patient with E coli early-onset sepsis was further compared with two gestational age-matched uninfected controls.

RESULTS

Compared with infants with non-E coli sepsis (n = 27), infants with E coli sepsis (n = 19) were more likely to have preterm birth, especially at less than 30 weeks of gestation (47% vs. 4%, p < 0.01), very low birth weights (<1500 g; 47% vs. 4%, p < 0.01), intrapartum fever (26% vs. 4%, p = 0.036), preterm premature rupture of membranes (PPROM; 74% vs. 11%, p < 0.01), prolonged rupture of membranes (>24 hours; 47% vs. 0%, p < 0.01), antibiotic use (63% vs. 15%, p < 0.01), and sepsis onset on the first day of life (63% vs. 15%, p < 0.01). After adjusting for gestational age, intrapartum fever (26% vs. 5%, p = 0.035) and PPROM (74% vs. 39%, p = 0.015) were more common in infants with E coli sepsis. Fifteen of the 19 E coli isolates (79%) were ampicillin-resistant, and three (16%) were gentamicin-resistant. Antepartum and intrapartum antibiotic exposure was associated with ampicillin-resistant E coli sepsis (100% vs. 43%, p < 0.01).

CONCLUSION

Early-onset E coli sepsis is more common in premature and very low birth weight infants and is more likely associated with intrapartum fever, PPROM, and sepsis onset on the first day of life than non-E coli sepsis. Broad-spectrum, multiple antibiotics or longer duration of antibiotic exposure may be associated with antibiotic-resistant pathogen infection.

Antibiotics for preterm rupture of membranes

BACKGROUND

Premature birth carries substantial neonatal morbidity and mortality. Subclinical infection is associated with preterm rupture of membranes (PROM). Prophylactic maternal antibiotic therapy might lessen infectious morbidity and delay labour, but could suppress labour without treating underlying infection.

OBJECTIVES

To evaluate the immediate and long-term effects of administering antibiotics to women with PROM before 37 weeks, on maternal infectious morbidity, neonatal morbidity and mortality, and longer-term childhood development.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (29 April 2010).

SELECTION CRITERIA

Randomised controlled trials comparing antibiotic administration with placebo that reported clinically relevant outcomes were included as were trials of different antibiotics. Trials in which no placebo was used were included for the outcome of perinatal death alone.

DATA COLLECTION AND ANALYSIS

We extracted data from each report without blinding of either the results or the treatments that women received. We sought unpublished data from a number of authors.

MAIN RESULTS

We included 22 trials, involving 6800 women and babies.The use of antibiotics following PROM is associated with statistically significant reductions in chorioamnionitis (average risk ratio (RR) 0.66, 95% confidence interval (CI) 0.46 to 0.96, and a reduction in the numbers of babies born within 48 hours (average RR 0.71, 95% CI 0.58 to 0.87) and seven days of randomisation (average RR 0.79, 95% CI 0.71 to 0.89). The following markers of neonatal morbidity were reduced: neonatal infection (RR 0.67, 95% CI 0.52 to 0.85), use of surfactant (RR 0.83, 95% CI 0.72 to 0.96), oxygen therapy (RR 0.88, 95% CI 0.81 to 0.96), and abnormal cerebral ultrasound scan prior to discharge from hospital (RR 0.81, 95% CI 0.68 to 0.98). Co-amoxiclav was associated with an increased risk of neonatal necrotising enterocolitis (RR 4.72, 95% CI 1.57 to 14.23).One study evaluated the children's health at seven years of age (ORACLE Children Study) and found antibiotics seemed to have little effect on the health of children.

AUTHORS' CONCLUSIONS

The decision to prescribe antibiotics for women with PROM is not clearcut. Benefits in some short-term outcomes (prolongation of pregnancy, infection, less abnormal cerebral ultrasound before discharge from hospital) should be balanced against a lack of evidence of benefit for others, including perinatal mortality, and longer term outcomes. If antibiotics are prescribed it is unclear which would be the antibiotic of choice.Co-amoxiclav should be avoided in women at risk of preterm delivery due to increased risk of neonatal necrotising enterocolitis.

Vaginal and oral microbes, host genotype and preterm birth

Preterm birth (PTB) is a leading cause of infant mortality and morbidity in the US and across the globe. Infection and associated inflammation are important initiators for PTB pathways; an estimated 40% of PTBs are attributed to amniochorionic-decidual or systemic inflammation. Historically, intrauterine infections have been implicated in PTB; recent evidence suggests that infections remote from the fetal site may also be causative. There is strong epidemiological evidence that bacterial vaginosis and periodontitis--two syndromes characterized by perturbations in the normal vaginal and oral bacterial microflora, respectively--are linked to infection-associated PTB. Oral and vaginal environments are similar in their bacterial microbiology; identical bacterial species have been independently isolated in periodontitis and bacterial vaginosis. Periodontitis and bacterial vaginosis also share many behavioral and sociodemographic risk factors suggesting a possible common pathophysiology. Genetic polymorphisms in host inflammatory responses to infection are shared between bacterial vaginosis, periodontitis and PTB, suggesting common mechanisms through which host genotype modify the effect of abnormal bacterial colonization on preterm birth. We review the state of knowledge regarding the risk of PTB attributable to perturbations in bacterial flora in oral and vaginal sites and the role of host genetics in modifying the risk of infection-related PTB. We posit that bacterial species that are common in perturbed vaginal and oral sites are associated with PTB through their interaction with the host immune system.

Use of antibiotics for the treatment of preterm parturition and prevention of neonatal morbidity: a metaanalysis

OBJECTIVE

We conducted a metaanalysis to determine whether antibiotics prolong pregnancy and reduce neonatal morbidity in preterm premature rupture of membranes (PPROM) and preterm labor (PTL) at 34 weeks or less.

STUDY DESIGN

Randomized trials comparing antibiotic therapy with placebo in PPROM or PTL at a gestation of 34 weeks or less were retrieved. The primary outcome was time to delivery (latency). Infant outcomes included mortality, infection, neurological abnormality, respiratory disease, and neonatal stay.

RESULTS

Antibiotics were associated with prolongation of pregnancy in PPROM (P < .01) but not PTL. Clinically diagnosed neonatal infections were reduced in both groups; there was a trend toward reduced culture-positive sepsis in PPROM. Intraventricular hemorrhage (all grades) was reduced in PPROM. Other neonatal outcomes were unaffected by antenatal antibiotics.

CONCLUSION

Antibiotics prolong pregnancy and reduce neonatal morbidity in women with PPROM at a gestation of 34 weeks or less. In PTL at a gestation of 34 weeks or less, there is little evidence of benefit from administration of antibiotics.

Preterm premature rupture of membranes: diagnosis, evaluation and management strategies

Preterm premature rupture of the membranes (PPROM) is responsible for one-third of all preterm births and affects 120,000 pregnancies in the United States each year. Effective treatment relies on accurate diagnosis and is gestational age dependent. The diagnosis of PPROM is made by a combination of clinical suspicion, patient history and some simple tests. PPROM is associated with significant maternal and neonatal morbidity and mortality from infection, umbilical cord compression, placental abruption and preterm birth. Subclinical intrauterine infection has been implicated as a major aetiological factor in the pathogenesis and subsequent maternal and neonatal morbidity associated with PPROM. The frequency of positive cultures obtained by transabdominal amniocentesis at the time of presentation with PPROM in the absence of labour is 25-40%. The majority of amniotic fluid infection in the setting of PPROM does not produce the signs and symptoms traditionally used as diagnostic criteria for clinical chorioamnionitis. Any evidence of infection by amniocentesis should be considered carefully as an indication for delivery. Documentation of amniotic fluid infection in women who present with PPROM enables us to triage our therapeutic decision making rationally. In PPROM, the optimal interval for delivery occurs when the risks of immaturity are outweighed by the risks of pregnancy prolongation (infection, abruption and cord accident). Lung maturity assessment may be a useful guide when planning delivery in the 32- to 34-week interval. A gestational age approach to therapy is important and should be adjusted for each hospital's neonatal intensive care unit. Antenatal antibiotics and corticosteroid therapies have clear benefits and should be offered to all women without contraindications. During conservative management, women should be monitored closely for placental abruption, infection, labour and a non-reassuring fetal status. Women with PPROM after 32 weeks of gestation should be considered for delivery, and after 34 weeks the benefits of delivery clearly outweigh the risks.

Antibiotics for preterm rupture of membranes

BACKGROUND

Premature birth carries substantial neonatal morbidity and mortality. One cause, associated with preterm rupture of membranes (pROM), is often subclinical infection. Maternal antibiotic therapy might lessen infectious morbidity and delay labour, but could suppress labour without treating underlying infection.

OBJECTIVES

To evaluate the immediate and long-term effects of administering antibiotics to women with pROM before 37 weeks, on maternal infectious morbidity, fetal and neonatal morbidity and mortality, and longer term childhood development.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (January 2003) and the Cochrane Controlled Trials Register (The Cochrane Library, Issue 4, 2002).

SELECTION CRITERIA

Randomised controlled trials comparing antibiotic administration with placebo that reported clinically relevant outcomes, were included. In addition, trials, in which no placebo was used, were included for the outcome of perinatal death alone.

DATA COLLECTION AND ANALYSIS

Data were extracted from each report without blinding of either the results or the treatments that women received. Unpublished data were sought from a number of authors.

MAIN RESULTS

Nineteen trials involving over 6000 women and their babies were included. The use of antibiotics following pROM is associated with a statistically significant reduction in chorioamnionitis (relative risk (RR) 0.57, 95% confidence interval (CI) 0.37 to 0.86). There was a reduction in the numbers of babies born within 48 hours (RR 0.71, 95% CI 0.58 to 0.87) and seven days of randomisation (RR 0.80, 95% CI 0.71 to 0.90). The following markers of neonatal morbidity were reduced: neonatal infection (RR 0.68, 95% CI 0.53 to 0.87), use of surfactant (RR 0.83, 95% CI 0.72 to 0.96), oxygen therapy (RR 0.88, 95% CI 0.81 to 0.96), and abnormal cerebral ultrasound scan prior to discharge from hospital (RR 0.82, 95% CI 0.68 to 0.98). Co-amoxiclav was associated with an increased risk of neonatal necrotising enterocolitis (RR 4.60, 95% CI 1.98 to 10.72).

REVIEWER'S CONCLUSIONS

Antibiotic administration following pROM is associated with a delay in delivery and a reduction in major markers of neonatal morbidity. These data support the routine use of antibiotics in pPROM. The choice as to which antibiotic would be preferred is less clear as, by necessity, fewer data are available. Co-amoxiclav should be avoided in women at risk of preterm delivery because of the increased risk of neonatal necrotising enterocolitis. From the available evidence, erythromycin would seem a better choice.