Premature rupture of membranes at 34 to 37 weeks' gestation: aggressive versus conservative management

Preterm prelabor rupture of membranes in singletons: maternal and neonatal outcomes

OBJECTIVES

To determine the effect of gestational age at delivery on maternal and neonatal outcomes in preterm prelabor rupture of membranes (PPROM) and assess various predictors of neonatal and infant mortality in these pregnancies.

METHODS

United States birth data from CDC-National Center for Health Statistics natality database for years 2004-2008 was used to identify singleton pregnancies with PPROM and delivery from 32 0/7 to 36 6/7 weeks. Controls were singletons at 37-40 weeks, without PPROM. Maternal and neonatal complications reported by all states were analyzed along with neonatal outcomes such as chorioamnionitis and hyaline membrane disease, reported by a subgroup of states. OR (95% CI) were calculated after adjusting for preeclampsia, diabetes, chronic hypertension, maternal race, and infant sex.

RESULTS

There were 134,502 PPROM cases and similar number of controls. There was a significant decrease in need for prolonged ventilation, hyaline membrane disease, 5 min Apgar score <7, and NICU admission with advancing gestational age. Placental abruption decreased and chorioamnionitis and cord prolapse were not different between 34 and 37 weeks. We found reductions in early death, neonatal death, and infant mortality with advancing gestational age (p<0.001 for each). Gestational age at delivery was the strongest predictor for early death, neonatal death, and infant mortality in PPROM. These differences persisted after adjusting for antenatal steroid use.

CONCLUSIONS

We provide population-based evidence showing a decrease in neonatal complications and death with advancing gestational age in PPROM. Gestational age at delivery in pregnancies with PPROM is the strongest predictor of mortality risk.

Ovarian Mature Cystic Teratoma is an Independent Risk Factor for the Premature Rupture of Membranes in Pregnancy: A Single-Center Retrospective Study

Background

Ovarian mature cystic teratomas (MCTs) are the most common tumors in pregnant women. The premature rupture of membranes (PROM) is a typical complication of pregnancy; however, the relationship between MCT and PROM is unknown. Therefore, we aimed to determine whether MCT is associated with the occurrence of PROM during pregnancy.

Methods

The data of patients with adnexal masses during pregnancy between January 2017 and August 2021 were retrospectively analyzed. Ovarian cystectomy was performed during cesarean delivery or after vaginal delivery. Univariate and multivariate logistic regression models were used for statistical analysis.

Results

A total of 234 patients with histopathological results were included. Among these patients, 21 occurred PROM during pregnancy, of which 11 were diagnosed with MCT. Compared with other subtypes, MCT (p=0.025) showed a stronger correlation with PROM and was an independent risk factor for PROM (odds ratio [OR], 2.811; 95% confidence interval [CI], 1.096-7.215; p=0.032). Furthermore, we found that MCT with a diameter >5 cm (p=0.0037) was more likely to promote the development of PROM than those that with a diameter <5 cm.

Conclusion

MCT was an independent risk factor for PROM during pregnancy. Positive actions and preventative clinical treatments should be fully taken into consideration by clinicians for pregnant women with MCTs, especially those ≥5 cm in diameter, to reduce the clinical complications related to MCT-associated PROM.

Immediate birth for women between 34 and 37 weeks of gestation with prolonged preterm prelabour rupture of membranes and detection of vaginal or urine group B streptococcus: an economic evaluation

Objective

What are the costs, benefits and harms of immediate birth compared with expectant management in women with prolonged preterm prelabour rupture of membranes (PPROM) at 34⁺⁰–36⁺⁶ weeks of gestation and detection of vaginal or urine group B streptococcus (GBS)?

Design

Mathematical decision model comprising three independent decision trees.

Setting

UK National Health Service (NHS) and personal social services perspective.

Population

Women testing positive for GBS with PPROM at 34⁺⁰–36⁺⁶ weeks of gestation.

Methods

The model estimates lifetime costs and quality‐adjusted life years (QALYs) using evidence from randomised trials, UK NHS data sources and further observational studies. Simulated events include neonatal infections, morbidity associated with preterm birth and consequences of caesarean birth. Deterministic and probabilistic sensitivity analyses (PSAs) were performed.

Main outcome measures

QALYs, costs and incremental cost‐effectiveness ratio (ICER).

Results

In this population, immediate birth dominates expectant management: it is more effective (average lifetime QALYs, 24.705 versus 24.371) and it is cheaper (average lifetime costs, £14,372 versus £19,311). In one‐way sensitivity analysis, results are robust to all but the odds ratio estimating the relative effect on incidence of infections. Threshold analysis shows that the odds of infection only need to be >1.5% with expectant management for the benefit of avoiding infections to outweigh the disadvantages of immediate birth. In PSA, immediate birth is the preferred option in >80% of simulations.

Conclusions

Neonatal GBS infections are expensive to treat and may result in substantial adverse health consequences. Therefore, immediate birth, which is associated with a reduced risk of neonatal infection compared with expectant management, is expected to generate better health outcomes and decreased lifetime costs.

Tweetable abstract

For women with preterm prelabour rupture of membranes and group B streptococcus in vaginal or urine samples, immediate birth is associated with improved health in their babies and reduced costs, compared with expectant management.

For women with preterm prelabour rupture of membranes and group B streptococcus in vaginal or urine samples, immediate birth is associated with improved health in their babies and reduced costs, compared with expectant management.

Association between latency period and perinatal outcomes after preterm premature rupture of membranes at 32-37 weeks of gestation: a perinatal registry-based cohort study

OBJECTIVES

To investigate association between latency after preterm premature rupture of membranes (PPROM) and perinatal outcomes at moderately and late preterm gestation.

METHODS

National perinatal registry-based cohort study using data for the period 2013-2018. Singleton pregnancies with non-malformed fetuses in cephalic presentation complicated by PPROM at 32⁺⁰-36⁺⁶ weeks were included. Associations between latency period and perinatal mortality, neonatal respiratory distress syndrome (RDS), early onset neonatal infection (EONI), and cesarean section were assessed using multiple logistic regression, adjusting for potential confounders (labor induction, maternal body-mass-index, maternal age, antenatal corticosteroids, and small-for-gestational-age). p<0.05 was considered statistically significant.

RESULTS

Of 3,017 pregnancies included, 365 (12.1%) had PPROM at 32⁺⁰-33⁺⁶ weeks and 2,652 (87.9%) at 34⁺⁰-36⁺⁶ weeks. Among all cases, 2,540 (84%) had latency <24 h (group A), 305 (10%) 24-47 h (group B), and 172 (6%) ≥48 h (group C). Longer latency was associated with higher incidence of EONI (adjusted odds ratio [aOR] 1.350; 95% confidence interval [CI] 0.900-2.026 for group B and aOR 2.500; 95% CI 1.599-3.911 for group C) and higher rate of caesarean section (aOR 2.465; 95% CI 1.763-3.447 for group B and aOR 1.854; 95% CI 1.172-2.932 for group C). Longer latency was not associated with rates of RDS (aOR 1.160; 95% CI 0.670-2.007 for group B and aOR 0.917; 95% CI 0.428-1.966 for group C).

CONCLUSIONS

In moderately to late PPROM, increased latency is associated with higher risk of EONI and cesarean section with no reduction in RDS.

Neonatal sepsis definitions from randomised clinical trials

INTRODUCTION

Neonatal sepsis is a leading cause of infant mortality worldwide with non-specific and varied presentation. We aimed to catalogue the current definitions of neonatal sepsis in published randomised controlled trials (RCTs).

METHOD

A systematic search of the Embase and Cochrane databases was performed for RCTs which explicitly stated a definition for neonatal sepsis. Definitions were sub-divided into five primary criteria for infection (culture, laboratory findings, clinical signs, radiological evidence and risk factors) and stratified by qualifiers (early/late-onset and likelihood of sepsis).

RESULTS

Of 668 papers screened, 80 RCTs were included and 128 individual definitions identified. The single most common definition was neonatal sepsis defined by blood culture alone (n = 35), followed by culture and clinical signs (n = 29), and then laboratory tests/clinical signs (n = 25). Blood culture featured in 83 definitions, laboratory testing featured in 48 definitions while clinical signs and radiology featured in 80 and 8 definitions, respectively.

DISCUSSION

A diverse range of definitions of neonatal sepsis are used and based on microbiological culture, laboratory tests and clinical signs in contrast to adult and paediatric sepsis which use organ dysfunction. An international consensus-based definition of neonatal sepsis could allow meta-analysis and translate results to improve outcomes.

Differences in clinical practice regarding screening and treatment of infections associated with spontaneous preterm birth: An international survey

OBJECTIVE

An association between infections in pregnancy and increased risk of preterm birth (PTB) is described in the literature. We anticipated that differences may exist in screening and treatment approaches for infections associated with PTB, within and between European countries. The aim of this study was to examine and analyse these differences in clinical practice in greater detail.

STUDY DESIGN

We created a descriptive survey examining the screening and treatment of infections in pregnancy. The survey was sent to European representatives of the International Spontaneous Preterm Birth Young Investigators (I-SPY) group in Europe, who sent it to their network. Finally, we had 50 respondents from ten European countries.

RESULTS

We found substantial differences in screening for bacterial vaginosis and asymptomatic bacteriuria, administration of antibiotics to women with preterm prelabour rupture of membranes (PPROM), and timing of induction of labour after PPROM. These differences in clinical practice were present both within, and between countries.

CONCLUSIONS

Approaches for screening and treatment of infections associated with PTB differ between European countries. There is a lack of robust evidence, which is reflected in a lack of uniformity in international guidelines. International collaboration is paramount to enlarge sample sizes in obstetric studies and to facilitate the process of developing, updating, and implementing consistent guidelines across Europe and beyond.

Preterm and term prelabour rupture of membranes: A review of timing and methods of labour induction

Prelabour rupture of membranes (PROM) exposes both foetuses and mothers to the risk of infection. Induction of labour has been proposed to reduce this risk, but its neonatal and maternal risks and benefits must be balanced against those of expectant management (EM). Recent randomized studies of preterm PROM show that EM until 37 weeks of gestation is associated with lower overall neonatal morbidity. In term PROM, active management is associated with a shorter birth interval but not with lower rates of neonatal infection. Similar maternal and neonatal outcomes are reported regardless of whether induction uses oxytocin, PGE2, or oral misoprostol.

Prophylactic anticoagulation for preterm premature rupture of membranes: a decision analysis

BACKGROUND

The current standard of care in the setting of preterm premature rupture of membranes involves antenatal hospitalization until delivery. The reduced physical activity during this time compounds the heightened risk for venous thromboembolism in pregnancy. Prophylactic anticoagulation can decrease this risk of venous thromboembolism; however, this benefit must be balanced against the risks of precluding neuraxial analgesia or increasing the risk of postpartum hemorrhage.

OBJECTIVE

The objective of this study was to determine the optimal modality for venous thromboembolism prophylaxis during hospitalization for preterm premature rupture of membranes using a decision analysis model.

STUDY DESIGN

A decision-analytical Markov model was constructed using the TreeAge software comparing the use of unfractionated heparin, low-molecular-weight heparin or no anticoagulation in women with a singleton pregnancy who were hospitalized for preterm premature rupture of membranes after 24 weeks and remained hospitalized until delivery. Maternal outcomes examined included attainment of neuraxial analgesia (vs no analgesia for vaginal delivery or general anesthesia for cesarean delivery), venous thromboembolism, postpartum hemorrhage, and maternal death. Probabilities and utilities were derived from existing literature. Sensitivity analyses were performed to interrogate model assumptions, and a Monte Carlo probabilistic sensitivity analysis was performed to examine the robustness of the model.

RESULTS

In this decision-analytical model, no prophylactic anticoagulation maximized maternal utilities. Clinical outcomes among a theoretical cohort of 100,000 women are shown in the Table. The 1- and 2-way sensitivity analyses supported this conclusion. Monte Carlo probabilistic sensitivity analysis indicated that no prophylaxis was the preferred choice in 56% of simulations, unfractionated heparin in 34% of simulations, and low-molecular-weight heparin in 10% of simulations.

CONCLUSION

Our results do not support the routine use of prophylactic anticoagulation in women admitted to the hospital for preterm premature rupture of membranes. These findings can be used to inform clinical decisions when admitting low-risk singleton pregnancies to the hospital in the setting of preterm premature rupture of membranes.

Preterm prelabor rupture of membranes: evaluating latency and neonatal morbidity for pregnancies with expectant management ≥34 weeks

Objective: To evaluate the association between latency and neonatal morbidity for pregnancies with expectant management of PPROM ≥34 w.Materials and Methods: A retrospective cohort of singletons with PPROM from 2011 to 2016. Exposure was defined as latency (period from diagnosis of PPROM to delivery) and was analyzed as a count variable (i.e. number of days) and binary variable (≥7 days and <7 days; ≥21 days and <21 days). Primary outcome was composite neonatal morbidity defined as need for respiratory support, culture positive neonatal sepsis, and/or neonatal antibiotics >72 h. Fisher's exact test, chi-square test, Mann-Whitney U and binary logistic regression tests were performed with p<.05 considered significant.Results: Of 813 pregnancies, 104 met inclusion criteria: 73 (70.2%) pregnancies with PPROM diagnosed at <34 weeks and 31 (29.8%) pregnancies with PPROM diagnosed ≥34 weeks. A total of 58 (55.8%) pregnancies had a latency of ≥7 days and 46 (44.2%) had a latency <7 days. There was no difference in composite neonatal morbidity for latency ≥7 d versus <7 d (aOR 0.92; 95% CI 0.30-2.82) or latency as a count variable (aOR 0.70; 95% CI 0.23-2.13). However, a latency ≥21 d was associated with increased composite neonatal morbidity (aOR 10.24, 95% CI 1.42-73.99).Conclusion: In pregnancies with PPROM expectantly managed ≥34 w, a latency of ≥7 d is not associated with significant differences in neonatal morbidity. However, different latency thresholds may be more clinically relevant for late preterm pregnancies. The increase in composite neonatal morbidity associated with a latency >21 days should be an area of future investigation and may suggest there is a population of pregnancies with PPROM which may not benefit from expectant management past 34 weeks.

A systematic scoping review of clinical indications for induction of labour

BACKGROUND

The proportion of women undergoing induction of labour (IOL) has risen in recent decades, with significant variation within countries and between hospitals. The aim of this study was to review research supporting indications for IOL and determine which indications are supported by evidence and where knowledge gaps exist.

METHODS

A systematic scoping review of quantitative studies of common indications for IOL. For each indication, we included systematic reviews/meta-analyses, randomised controlled trials (RCTs), cohort studies and case control studies that compared maternal and neonatal outcomes for different modes or timing of birth. Studies were identified via the databases PubMed, Maternity and Infant Care, CINAHL, EMBASE, and ClinicalTrials.gov from between April 2008 and November 2019, and also from reference lists of included studies. We identified 2554 abstracts and reviewed 300 full text articles. The quality of included studies was assessed using the RoB 2.0, the ROBINS-I and the ROBIN tool.

RESULTS

68 studies were included which related to post-term pregnancy (15), hypertension/pre-eclampsia (15), diabetes (9), prelabour rupture of membranes (5), twin pregnancy (5), suspected fetal compromise (4), maternal elevated body mass index (BMI) (4), intrahepatic cholestasis of pregnancy (3), suspected macrosomia (3), fetal gastroschisis (2), maternal age (2), and maternal cardiac disease (1). Available evidence supports IOL for women with post-term pregnancy, although the evidence is weak regarding the timing (41 versus 42 weeks), and for women with hypertension/preeclampsia in terms of improved maternal outcomes. For women with preterm premature rupture of membranes (24-37 weeks), high-quality evidence supports expectant management rather than IOL/early birth. Evidence is weakly supportive for IOL in women with term rupture of membranes. For all other indications, there were conflicting findings and/or insufficient power to provide definitive evidence.

CONCLUSIONS

While for some indications, IOL is clearly recommended, a number of common indications for IOL do not have strong supporting evidence. Overall, few RCTs have evaluated the various indications for IOL. For conditions where clinical equipoise regarding timing of birth may still exist, such as suspected macrosomia and elevated BMI, researchers and funding agencies should prioritise studies of sufficient power that can provide quality evidence to guide care in these situations.

No. 233-Antibiotic Therapy in Preterm Premature Rupture of the Membranes

OBJECTIVE

To review the evidence and provide recommendations on the use of antibiotics in preterm premature rupture of the membranes (PPROM).

OUTCOMES

Outcomes evaluated include the effect of antibiotic treatment on maternal infection, chorioamnionitis, and neonatal morbidity and mortality.

EVIDENCE

Published literature was retrieved through searches of Medline, EMBASE, CINAHL, and The Cochrane Library, using appropriate controlled vocabulary and key words (PPROM, infection, and antibiotics). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and new material incorporated in the guideline to July 2008. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The evidence obtained was reviewed and evaluated by the Infectious Diseases Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) under the leadership of the principal authors, and recommendations were made according to guidelines developed by the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Guideline implementation should assist the practitioner in developing an approach to the use of antibiotics in women with PPROM. Patients will benefit from appropriate management of this condition.

VALIDATION

This guideline has been reviewed and approved by the Infectious Diseases Committee and the Maternal Fetal Medicine Committee of the SOGC, and approved by the Executive and Council of the SOGC.

SPONSOR

The Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

Can we predict preterm delivery in patients with premature rupture of membranes?

PURPOSE

To characterize the parameters that predict preterm delivery in patients with preterm, premature rupture of membranes.

METHODS

This retrospective cohort study included women diagnosed with preterm premature rupture of membranes at 24-34 weeks gestation. Demographics, medical history, laboratory tests, and delivery data were reviewed.

RESULTS

Among 258 patients with preterm, premature rupture of membranes during the study period, 141 (54.7%) met the inclusion criteria. Therefore, the final cohort included 141 (54.78%) women, among whom, 32 (22.7%) delivered within the first 24 h of ROM and 109 (77.3%) delivered after 24 h. Univariant analysis revealed that advanced gestational age at the time of preterm, premature rupture of membranes, larger cervical dilation and leukocyte count at admission had significant effects on the likelihood of labor within 24 h. Analysis of the differences between each patient at admission to 24 h before labor in heart rate, temperature (fever), leukocyte counts and amniotic fluid color revealed significant changes in heart rate (P < 0.001), leukocyte count (P < 0.001) and in amniotic fluid from clean to meconium or bloody (P < 0.001). There was no significant change in elevated temperature (P = 0.065).

CONCLUSIONS

Our findings indicate that minimal changes in heart rate, body temperature (fever), leukocyte count and amniotic fluid color, within normal ranges, appear 24 h before delivery, among women with preterm, premature rupture of membranes and prolonged latency period. Increased attention to these changes might enable better follow-up and timing of delivery for patients with preterm, premature rupture of membranes before 34 weeks gestation.

[Modalities of birth in case of uncomplicated preterm premature rupture of membranes: CNGOF Preterm Premature Rupture of Membranes Guidelines]

OBJECTIVE

To identify the ideal gestational age at delivery for preterm premature rupture of membranes and modalities of birth.

METHOD

To identify studies, research was conducted using Pub-Med, Embase and Cochrane databases.

RESULTS

Prolonged latency duration after pPROM does not worsen neonatal prognosis (NP3). Therefore, it is recommended not to deliver before 34 weeks of gestation for patient with uncomplicated preterm rupture of membranes (pPROM) (Grade C). After 34 weeks of gestation, expectant management for pPROM is not associated with neonatal sepsis (NP1) but is associated to intra-uterine infection (NP2). Early delivery is associated with higher risk of respiratory distress syndrome (NP2), higher risk of cesarean section (NP2) and longer duration of NICU hospitalization (NP2). Before 37 weeks of gestation, expectant management is recommended for uncomplicated pPROM (Grade A), even if vaginal group B streptococcus is positive, as long as antibiotics are used at the time of membranes rupture (Professional consensus). Elective cesarean section is reserved for usual obstetrical indications. Oxytocin and prostaglandins are reasonable options for inducing labor (Professional consensus). Data are too scarce to establish recommendation regarding intra-cervical balloons in case of pPROM (Professional consensus).

CONCLUSION

Expectant management is recommended for uncomplicated pPROM before 37 weeks of gestation.

Risk Factors for Neonatal Sepsis in Pregnant Women with Premature Rupture of the Membrane

Background

Premature rupture of the membrane (PROM) is associated with high maternal as well as perinatal morbidity and mortality risks. It occurs in 5 to 10% of all pregnancy while incidence of amniotic membrane infection varies from 6 to 10%. This study aimed to determine the incidence of neonatal sepsis in Cipto Mangunkusumo Hospital and the risk factors.

Methods

A cross-sectional study was done in Cipto Mangunkusumo Hospital, Jakarta, from December 2016 to June 2017. The study used total sampling method including all pregnant women with gestational age of 20 weeks or more experiencing PROM, who came to the hospital at that time. Samples with existing comorbidities such as diabetes mellitus or other serious systemic illnesses such as heart disease or autoimmune condition were excluded from the analysis.

Results

A total of 405 pregnant women with PROM were included in this study. There were 21 cases (5.2%) of neonatal sepsis. The analysis showed that risk of neonatal sepsis was higher in pregnant women with prolonged rupture of membrane for ≥ 18 hours before hospital admission (OR 3.08), prolonged rupture of membrane for ≥ 15 hours during hospitalization (OR 7.32), and prolonged rupture of membrane for ≥ 48 hours until birth (OR 5.77). The risk of neonatal sepsis was higher in preterm pregnancy with gestational age of <37 weeks (OR 18.59).

Conclusion

Risk of neonatal sepsis is higher in longer duration of prolonged rupture of membrane as well as preterm pregnancy.

Which method is best for the induction of labour? A systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

More than 150,000 pregnant women in England and Wales have their labour induced each year. Multiple pharmacological, mechanical and complementary methods are available to induce labour.

OBJECTIVE

To assess the relative effectiveness, safety and cost-effectiveness of labour induction methods and, data permitting, effects in different clinical subgroups.

METHODS

We carried out a systematic review using Cochrane methods. The Cochrane Pregnancy and Childbirth Group's Trials Register was searched (March 2014). This contains over 22,000 reports of controlled trials (published from 1923 onwards) retrieved from weekly searches of OVID MEDLINE (1966 to current); Cochrane Central Register of Controlled Trials (The Cochrane Library); EMBASE (1982 to current); Cumulative Index to Nursing and Allied Health Literature (1984 to current); ClinicalTrials.gov; the World Health Organization International Clinical Trials Registry Portal; and hand-searching of relevant conference proceedings and journals. We included randomised controlled trials examining interventions to induce labour compared with placebo, no treatment or other interventions in women eligible for third-trimester induction. We included outcomes relating to efficacy, safety and acceptability to women. In addition, for the economic analysis we searched the Database of Abstracts of Reviews of Effects, and Economic Evaluations Databases, NHS Economic Evaluation Database and the Health Technology Assessment database. We carried out a network meta-analysis (NMA) using all of the available evidence, both direct and indirect, to produce estimates of the relative effects of each treatment compared with others in a network. We developed a de novo decision tree model to estimate the cost-effectiveness of various methods. The costs included were the intervention and other hospital costs incurred (price year 2012-13). We reviewed the literature to identify preference-based utilities for the health-related outcomes in the model. We calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit. We represent uncertainty in the optimal intervention using cost-effectiveness acceptability curves.

RESULTS

We identified 1190 studies; 611 were eligible for inclusion. The interventions most likely to achieve vaginal delivery (VD) within 24 hours were intravenous oxytocin with amniotomy [posterior rank 2; 95% credible intervals (CrIs) 1 to 9] and higher-dose (≥ 50 µg) vaginal misoprostol (rank 3; 95% CrI 1 to 6). Compared with placebo, several treatments reduced the odds of caesarean section, but we observed considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best three treatments, whereas vaginal misoprostol (≥ 50 µg) was most likely to increase the odds of excessive uterine activity. For other safety outcomes there were insufficient data or there was too much uncertainty to identify which treatments performed 'best'. Few studies collected information on women's views. Owing to incomplete reporting of the VD within 24 hours outcome, the cost-effectiveness analysis could compare only 20 interventions. The analysis suggested that most interventions have similar utility and differ mainly in cost. With a caveat of considerable uncertainty, titrated (low-dose) misoprostol solution and buccal/sublingual misoprostol had the highest likelihood of being cost-effective.

LIMITATIONS

There was considerable uncertainty in findings and there were insufficient data for some planned subgroup analyses.

CONCLUSIONS

Overall, misoprostol and oxytocin with amniotomy (for women with favourable cervix) is more successful than other agents in achieving VD within 24 hours. The ranking according to safety of different methods was less clear. The cost-effectiveness analysis suggested that titrated (low-dose) oral misoprostol solution resulted in the highest utility, whereas buccal/sublingual misoprostol had the lowest cost. There was a high degree of uncertainty as to the most cost-effective intervention.

FUTURE WORK

Future trials should be powered to detect a method that is more cost-effective than misoprostol solution and report outcomes included in this NMA.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005116.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

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.

Planned early birth versus expectant management for women with preterm prelabour rupture of membranes prior to 37 weeks' gestation for improving pregnancy outcome

BACKGROUND

Current management of preterm prelabour rupture of the membranes (PPROM) involves either initiating birth soon after PPROM or, alternatively, adopting a 'wait and see' approach (expectant management). It is unclear which strategy is most beneficial for mothers and their babies. This is an update of a Cochrane review published in 2010 (Buchanan 2010).

OBJECTIVES

To assess the effect of planned early birth versus expectant management for women with preterm prelabour rupture of the membranes between 24 and 37 weeks' gestation for fetal, infant and maternal well being.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (30 September 2016), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials comparing planned early birth with expectant management for women with PPROM prior to 37 weeks' gestation. We excluded quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated trials for inclusion into the review and for methodological quality. Two review authors independently extracted data. We checked data for accuracy. We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We included 12 trials in the review (3617 women and 3628 babies). For primary outcomes, we identified no clear differences between early birth and expectant management in neonatal sepsis (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.66 to 1.30, 12 trials, 3628 babies, evidence graded moderate), or proven neonatal infection with positive blood culture (RR 1.24, 95% CI 0.70 to 2.21, seven trials, 2925 babies). However, early birth increased the incidence of respiratory distress syndrome (RDS) (RR 1.26, 95% CI 1.05 to 1.53, 12 trials, 3622 babies, evidence graded high). Early birth was also associated with an increased rate of caesarean section (RR 1.26, 95% CI 1.11 to 1.44, 12 trials, 3620 women, evidence graded high).Assessment of secondary perinatal outcomes showed no clear differences in overall perinatal mortality (RR 1.76, 95% CI 0.89 to 3.50, 11 trials, 3319 babies), or intrauterine deaths (RR 0.45, 95% CI 0.13 to 1.57, 11 trials, 3321 babies) when comparing early birth with expectant management. However, early birth was associated with a higher rate of neonatal death (RR 2.55, 95% CI 1.17 to 5.56, 11 trials, 3316 babies) and need for ventilation (RR 1.27, 95% CI 1.02 to 1.58, seven trials, 2895 babies, evidence graded high). Babies of women randomised to early birth were delivered at a gestational age lower than those randomised to expectant management (mean difference (MD) -0.48 weeks, 95% CI -0.57 to -0.39, eight trials, 3139 babies). Admission to neonatal intensive care was more likely for those babies randomised to early birth (RR 1.16, 95% CI 1.08 to 1.24, four trials, 2691 babies, evidence graded moderate).In assessing secondary maternal outcomes, we found that early birth was associated with a decreased rate of chorioamnionitis (RR 0.50, 95% CI 0.26 to 0.95, eight trials, 1358 women, evidence graded moderate), and an increased rate of endometritis (RR 1.61, 95% CI 1.00 to 2.59, seven trials, 2980 women). As expected due to the intervention, women randomised to early birth had a higher chance of having an induction of labour (RR 2.18, 95% CI 2.01 to 2.36, four trials, 2691 women). Women randomised to early birth had a decreased total length of hospitalisation (MD -1.75 days, 95% CI -2.45 to -1.05, six trials, 2848 women, evidence graded moderate).Subgroup analyses indicated improved maternal and infant outcomes in expectant management in pregnancies greater than 34 weeks' gestation, specifically relating to RDS and maternal infections. The use of prophylactic antibiotics were shown to be effective in reducing maternal infections in women randomised to expectant management.Overall, we assessed all 12 studies as being at low or unclear risk of bias. Some studies lacked an adequate description of methods and the risk of bias could only be assessed as unclear. In five of the studies there were one and/or two domains where the risk of bias was judged as high. GRADE profiling showed the quality of evidence across all critical outcomes to be moderate to high.

AUTHORS' CONCLUSIONS

With the addition of five randomised controlled trials (2927 women) to this updated review, we found no clinically important difference in the incidence of neonatal sepsis between women who birth immediately and those managed expectantly in PPROM prior to 37 weeks' gestation. Early planned birth was associated with an increase in the incidence of neonatal RDS, need for ventilation, neonatal mortality, endometritis, admission to neonatal intensive care, and the likelihood of birth by caesarean section, but a decreased incidence of chorioamnionitis. Women randomised to early birth also had an increased risk of labour induction, but a decreased length of hospital stay. Babies of women randomised to early birth were more likely to be born at a lower gestational age.In women with PPROM before 37 weeks' gestation with no contraindications to continuing the pregnancy, a policy of expectant management with careful monitoring was associated with better outcomes for the mother and baby.The direction of future research should be aimed at determining which groups of women with PPROM would not benefit from expectant management. This could be determined by analysing subgroups according to gestational age at presentation, corticosteroid usage, and abnormal vaginal microbiological colonisation. Research should also evaluate long-term neurodevelopmental outcomes of infants.

An economic evaluation of planned immediate versus delayed birth for preterm prelabour rupture of membranes: findings from the PPROMT randomised controlled trial

OBJECTIVE

This study is an economic evaluation of immediate birth compared with expectant management in women with preterm prelabour rupture of the membranes near term (PPROMT).

DESIGN

A cost-effectiveness analysis alongside the PPROMT randomised controlled trial.

SETTING

Obstetric departments in 65 hospitals across 11 countries.

POPULATION

Women with a singleton pregnancy with ruptured membranes between 34⁺⁰ and 36⁺⁶ weeks gestation.

METHODS

Women were randomly allocated to immediate birth or expectant management. Costs to the health system were identified and valued. National hospital costing data from both the UK and Australia were used. Average cost per recruit in each arm was calculated and 95% confidence intervals were estimated using bootstrap re-sampling. Averages costs during antenatal care, delivery and postnatal care, and by country were estimated.

MAIN OUTCOMES MEASURES

Total mean cost difference between immediate birth and expectant management arms of the trial.

RESULTS

From 11 countries 923 women were randomised to immediate birth and 912 were randomised to expectant management. Total mean costs per recruit were £8852 for immediate birth and £8740 for expectant delivery resulting in a mean difference in costs of £112 (95% CI: -431 to 662). The expectant management arm had significantly higher antenatal costs, whereas the immediate birth arm had significantly higher delivery and neonatal costs. There was large variation between total mean costs by country.

CONCLUSION

This economic evaluation found no evidence that expectant management was more or less costly than immediate birth. Outpatient management may offer opportunities for cost savings for those women with delayed delivery.

TWEETABLE ABSTRACT

For women with preterm prelabour rupture of the membranes, the relative benefits and harms of immediate and expectant management should inform counselling as costs are similar.

Supplemental Analyses of Recent Trends in Infant Mortality

U.S. preliminary data for 2002 show a significant increase in the infant mortality rate to 7.0 infant deaths per 1,000 live births, the first rise in the infant mortality rate since 1958. The increase in infant mortality was concentrated in the neonatal period, particularly in deaths occurring within seven days of birth. Partially edited fetal death data suggest that the increase in neonatal mortality was accompanied by a decline in the late fetal mortality rate, and thus it appears that the 2002 perinatal mortality rate will remain level. Potential explanatory factors for the changes in the infant mortality rate are examined, including causes of infant death, percentage of births that are preterm, and low birthweight. Data from the 2002 linked birth and infant death file will allow an assessment of the contribution of maternal and infant factors such as multiple births and management of labor and delivery.

Explaining the 2001–2002 Infant Mortality Increase in the United States: Data from the Linked Birth/Infant Death Data Set

The U.S. infant mortality rate (IMR) increased from 6.8 infant deaths per 1,000 live births in 2001 to 7.0 in 2002, the first increase in more than 40 years. From 2001 to 2002, IMR increased for very low birthweight infants as well as for preterm and very preterm infants. Although IMR for very low birthweight infants increased, most of the increase in IMR from 2001 to 2002 was due to a change in the distribution of births by birthweight and, more specifically, to an increase in infants born weighing less than 750 grams. The majority of infants born at less than 750 grams die within the first year of life; thus, these births contribute disproportionately to overall IMR. Increases in births at less than 750 grams occurred for non-Hispanic white, non-Hispanic black, and Hispanic women. Most of the increase occurred among mothers 20 to 34 years of age. Although multiple births contributed disproportionately, most of the increase in births at less than 750 grams occurred among singletons. Three hypotheses were evaluated to assess their possible impact on the increase in less than 750-gram births: possible changes in (1) the reporting of births or fetal deaths, (2) the risk profile of births, and (3) medical management of pregnancy. Although each of these factors may have contributed to the increase, the relative effects of these and other factors remain unclear. More detailed studies are needed to further explain the 2001–2002 infant mortality increase.

Immediate delivery compared with expectant management after preterm pre-labour rupture of the membranes close to term (PPROMT trial): a randomised controlled trial

BACKGROUND

Preterm pre-labour ruptured membranes close to term is associated with increased risk of neonatal infection, but immediate delivery is associated with risks of prematurity. The balance of risks is unclear. We aimed to establish whether immediate birth in singleton pregnancies with ruptured membranes close to term reduces neonatal infection without increasing other morbidity.

METHODS

The PPROMT trial was a multicentre randomised controlled trial done at 65 centres across 11 countries. Women aged over 16 years with singleton pregnancies and ruptured membranes before the onset of labour between 34 weeks and 36 weeks and 6 days weeks who had no signs of infection were included. Women were randomly assigned (1:1) by a computer-generated randomisation schedule with variable block sizes, stratified by centre, to immediate delivery or expectant management. The primary outcome was the incidence of neonatal sepsis. Secondary infant outcomes included a composite neonatal morbidity and mortality indicator (ie, sepsis, mechanical ventilation ≥24 h, stillbirth, or neonatal death); respiratory distress syndrome; any mechanical ventilation; and duration of stay in a neonatal intensive or special care unit. Secondary maternal outcomes included antepartum or intrapartum haemorrhage, intrapartum fever, postpartum treatment with antibiotics, and mode of delivery. Women and caregivers could not be masked, but those adjudicating on the primary outcome were masked to group allocation. Analyses were by intention to treat. This trial is registered with the International Clinical Trials Registry, number ISRCTN44485060.

FINDINGS

Between May 28, 2004, and June 30, 2013, 1839 women were recruited and randomly assigned: 924 to the immediate birth group and 915 to the expectant management group. One woman in the immediate birth group and three in the expectant group were excluded from the primary analyses. Neonatal sepsis occurred in 23 (2%) of 923 neonates whose mothers were assigned to immediate birth and 29 (3%) of 912 neonates of mothers assigned to expectant management (relative risk [RR] 0·8, 95% CI 0·5-1·3; p=0·37). The composite secondary outcome of neonatal morbidity and mortality occurred in 73 (8%) of 923 neonates of mothers assigned to immediate delivery and 61 (7%) of 911 neonates of mothers assigned to expectant management (RR 1·2, 95% CI 0·9-1·6; p=0·32). However, neonates born to mothers in the immediate delivery group had increased rates of respiratory distress (76 [8%] of 919 vs 47 [5%] of 910, RR 1·6, 95% CI 1·1-2·30; p=0·008) and any mechanical ventilation (114 [12%] of 923 vs 83 [9%] of 912, RR 1·4, 95% CI 1·0-1·8; p=0·02) and spent more time in intensive care (median 4·0 days [IQR 0·0-10·0] vs 2·0 days [0·0-7·0]; p<0·0001) compared with neonates born to mothers in the expectant management group. Compared with women assigned to the immediate delivery group, those assigned to the expectant management group had higher risks of antepartum or intrapartum haemorrhage (RR 0·6, 95% CI 0·4-0·9), intrapartum fever (0·4, 0·2-0·9), and use of postpartum antibiotics (0·8, 0·7-1·0), and longer hospital stay (p<0·0001), but a lower risk of caesarean delivery (RR 1·4, 95% CI 1·2-1·7).

INTERPRETATION

In the absence of overt signs of infection or fetal compromise, a policy of expectant management with appropriate surveillance of maternal and fetal wellbeing should be followed in pregnant women who present with ruptured membranes close to term.

FUNDING

Australian National Health and Medical Research Council, the Women's and Children's Hospital Foundation, and The University of Sydney.

Timing of Histologic Progression from Chorio-Deciduitis to Chorio-Deciduo-Amnionitis in the Setting of Preterm Labor and Preterm Premature Rupture of Membranes with Sterile Amniotic Fluid

Background

Histologic chorio-deciduitis and chorio-deciduo-amnionitis (amnionitis) in extra-placental membranes are known to represent the early and advanced stages of ascending intra-uterine infection. However, there are no data in humans about the time required for chorio-deciduitis to develop and for chorio-deciduitis without amnionitis to progress to chorio-deciduitis with amnionitis, and the effect of prolongation of pregnancy on the development of chorio-deciduitis and amnionitis in patients with preterm labor and intact membranes (PTL) and preterm premature rupture of membranes (preterm-PROM). We examined these issues in this study.

Methods

The study population consisted of 289 women who delivered preterm (133 cases with PTL, and 156 cases with preterm-PROM) and who had sterile amniotic fluid (AF) defined as a negative AF culture and the absence of inflammation as evidenced by a matrix metalloproteinase-8 (MMP-8) level <23 ng/ml. We examined the association between amniocentesis-to-delivery interval and inflammatory status in the extra-placental membranes (i.e., inflammation-free extra-placental membranes, choroi-deciduitis only, and chorio-deciduitis with amnionitis) in patients with PTL and preterm-PROM.

Results

Amniocentesis-to-delivery interval was longer in cases of chorio-deciduitis with amnionitis than in cases of chorio-deciduitis only in both PTL (median [interquartile-range (IQR)]; 645.4 [319.5] vs. 113.9 [526.9] hours; P = 0.005) and preterm-PROM (131.3 [135.4] vs. 95.2 [140.5] hours; P<0.05). Amniocentesis-to-delivery interval was an independent predictor of the development of both chorio-deciduitis and amnionitis after correction for confounding variables such as gestational age at delivery in the setting of PTL, but not preterm-PROM.

Conclusions

These data confirm for the first time that, in cases of both PTL and preterm-PROM with sterile AF, more time is required to develop chorio-deciduitis with amnionitis than chorio-deciduitis alone in extra-placental membranes. Moreover, prolongation of pregnancy is an independent predictor of the development of both chorio-deciduitis and amnionitis in cases of PTL with sterile AF.

Preterm premature rupture of membranes (PPROM): outcomes of delivery at 32(°/7)-33(6/7) weeks after confirmed fetal lung maturity (FLM) versus expectant management until 34(°/7) weeks

OBJECTIVE

Our objective was to compare maternal and neonatal outcomes in patients with preterm premature rupture of membranes (PPROM) delivered prior to 34(°/7) weeks upon confirmation of fetal lung maturity (FLM) to those managed expectantly until 34(°/7) weeks.

METHODS

We performed a retrospective cohort study of non-anomalous singleton gestations with PPROM occurring after 24 weeks delivered between 32(°/7) and 34(°/7) weeks from 2004 to 2012. Patients delivered upon documented FLM (+FLM)--defined as the presence of phosphatidylglycerol (PG) at 32(°/7)-33(6/7) weeks if amniotic fluid was obtainable vaginally--were compared with patients delivered without documented FLM between 32(°/7) and 34(°/7) weeks (expectant). Primary outcomes included maternal infection (clinically diagnosed endometritis or chorioamnionitis), placental abruption and a composite of neonatal morbidities (including but not limited to mechanical ventilation, intraventricular hemorrhage, necrotizing enterocolitis, sepsis and respiratory distress syndrome). Statistical analysis was performed using Student's t-test for continuous variables and Chi-square or Fisher's exact test for categorical data. Covariates were analyzed via multivariate logistic regression and adjusted odds ratios were calculated.

RESULTS

Of 237 PPROMs delivered at 32(°/7)-34(°/7) weeks, 74 were intentionally delivered for +FLM and 163 were expectantly managed. No cord prolapse or stillbirth was observed. Maternal infection (chorioamnionitis or endometritis) was lower in the +FLM group (aOR 0.33 95% CI 0.12-0.88). Overall, there was no difference in composite neonatal morbidity did not differ between the two groups (aOR 1.36 95% CI 0.53-3.54).

CONCLUSIONS

In patients with PPROM, delivery after confirmation of FLM at 32(°/7)-33(6/7) weeks compared with expectant management until 34(°/7) weeks may prevent maternal infection without increasing neonatal morbidity.

Premature rupture of membranes and neonatal respiratory morbidity at 32-41 weeks' gestation: a retrospective single-center cohort study

AIM

To ascertain whether premature rupture of membranes (PROM) independently affects the risk of neonatal respiratory morbidity at 32-41 weeks' gestation because previous reports have given insufficient consideration to the mode of delivery and labor onset.

METHODS

Data on 4,629 consecutive singleton infants were retrospectively collected. Respiratory morbidity was limited to respiratory distress syndrome and transient tachypnea of the newborn, both of which are related to prematurity. Delivery modes were divided into four groups based on the existence of PROM and of labor onset, and the respiratory morbidity was examined according to the number of weeks of gestational age. Multivariate analysis including PROM and delivery mode was conducted to examine the association of respiratory morbidity.

RESULTS

Respiratory morbidity or a positive pressure requirement delivered after PROM and intact amniochorionic membranes accompanied by labor were similar at all weeks. Around 37 weeks, the absence of labor onset was associated with a risk of respiratory morbidity or positive pressure requirement. Significant respiratory risk was not associated with the incidence of PROM (adjusted odds ratio [aOR], 0.98; 95% confidence interval [CI], 0.52-1.83), interval from rupture to delivery (aOR, 1.00; 95% CI, 0.99-1.01), clinical chorioamnionitis, induction management, pregnancy-related complications, or neonatal sex. Delivery by Cesarean section and early gestational age presented a significant risk for respiratory morbidity.

CONCLUSIONS

Neither PROM nor latency after PROM at 32-41 weeks affected neonatal respiratory morbidity. Avoiding Cesarean section instead of simply increasing the time to delivery may help to reduce respiratory morbidity.

Conservative management of preterm premature rupture of membranes beyond 32 weeks' gestation: is it worthwhile?

We aimed to investigate whether conservative management of preterm premature rupture of membranes (PPROM) at 32-34 weeks' gestation improves outcome. In this retrospective analysis of singleton pregnancies, the study group included patients with PPROM at 28-34 weeks' gestation and the control group included patients presented with spontaneous preterm delivery at 28-34 weeks' gestation. Both groups were subdivided according to gestational age - early (28-31 weeks' gestation) versus late (32-34 weeks' gestation). Adverse neonatal outcome included neonatal death, intraventricular haemorrhage grade 3/4, respiratory distress syndrome, periventricular leucomalacia and neonatal sepsis. The study and control groups included 94 and 86 women, respectively. The study group had a lower incidence of adverse neonatal outcome at the earlier weeks (28-31), compared with the control group at the same gestational age. In contrast, at 32-34 weeks' gestation no difference in the risk for adverse neonatal outcome was noticed. Additionally, within the study group, chorioamnionitis rate was significantly higher among those who delivered at 32-34 weeks' gestation (p < 0.01). No advantage for conservative management of PPROM was demonstrated beyond 31 weeks' gestation. Moreover, conservative management of PPROM at 32-34 weeks' gestation may expose both mother and neonate to infectious morbidity.

Obstetric and neonatal outcomes after preterm premature rupture of membranes among women carrying group B streptococcus

OBJECTIVE

To evaluate whether carriers of group B streptococcus (GBS) have adverse obstetric and neonatal outcomes when preterm premature rupture of membranes (PPROM) occurs.

METHODS

In a retrospective study, data were reviewed for women with a singleton pregnancy and PPROM before 34 weeks who attended the Meir Medical Center, Kfar Saba, Israel, between 2005 and 2012. All women received roxithromycin for 1 week, and ampicillin until GBS culture results were available. Ampicillin was continued to 1 week if the GBS culture was positive. The primary study outcome measure was the latency period (time from rupture of membranes to active/induced labor).

RESULTS

Among 116 eligible patients, 21 (18.1%) were GBS carriers and 95 (81.9%) noncarriers. The latency period was 11.2 ± 18.1 days for GBS carriers versus 7.5 ± 9.6 days for noncarriers (P=0.93). However, there was a correlation between the length of ampicillin treatment and the latency period (Spearman correlation coefficient 0.7; P<0.001). There were no differences in early neonatal outcomes.

CONCLUSION

GBS carriers with PPROM did not have adverse outcomes. Longer treatment with ampicillin among GBS carriers prolonged the latency period.

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.

[Rupture of membranes: pathophysiology, diagnosis, consequences and management]

Rupture of membranes (ROM) depends on mechanical stretch, extracellular matrix components imbalance and increased apoptosis. It occurs in 2 to 3% of all pregnancies before 37 weeks' gestation (WG) and in up to 10% at term. Main consequences are labor induction and risk of maternal-fetal infection. ROM is associated with one third of preterm births and about 20% of perinatal mortality. This review deals with recent knowledge concerning ROM including diagnosis and management. In many cases, ROM is easily identified by clinical examination. In other cases, the use of vaginal pH appears to be less efficient than the use of immunochromatographic strips based on IGFBP-1 or PAMG-1 detection. Before 34WG, conservative management consists in in utero transfer, antibioprophylaxis and corticosteroids. After 37WG, delivery is the most appropriate option. Between 34 and 37WG, recent studies demonstrate that induction of labour does not improve pregnancy outcomes. Therefore, expectant management can be the first option between 34 and 37WG when no active infection is suspected especially in case of unfavourable cervix.

Neonatal outcomes are associated with latency after preterm premature rupture of membranes

OBJECTIVE

To determine factors associated with latency time to birth after preterm premature rupture of membranes (PPROM) and the impact on neonatal outcomes.

STUDY DESIGN

Data on singleton pregnancies with PPROM (n=1535 infants) were prospectively collected in a computerized perinatal/neonatal database at a tertiary care perinatal center. Latency was characterized as ≤72h versus >72 h after PPROM.

RESULT

The percentage of women with latency to birth >72 h decreased from 67% in very preterm (gestational age (GA) 25 to 28 weeks) to 10% in late preterm women (GA 33 to 36 weeks). PPROM women with latency ≤72 h were more likely to have pregnancy-induced hypertension and birth weight <3%; PPROM women with latency >72 h were more likely to have received steroids and develop clinical chorioamnionitis. PPROM <32 weeks GA with latency ≤72 h was associated with a two-fold higher incidence of severe neonatal morbidity, while PPROM between 29 to 34 weeks GA and latency ≤72 h was associated with a higher incidence of moderate neonatal morbidity.

CONCLUSION

A latency period >72 h was associated with a decreased incidence of adverse neonatal outcomes up to 32 weeks GA for severe and 34 weeks GA for moderate morbidity indices.

Management of late-preterm premature rupture of membranes: the PPROMEXIL-2 trial

OBJECTIVE

The evidence for the management of near term prelabor rupture of membranes is poor. From January 2007 until September 2009, we performed the PPROM Expectant Management versus Induction of Labor (PPROMEXIL) trial. In this trial, we showed that in women with preterm prelabor rupture of membranes (PPROM), the incidence of neonatal sepsis was low, and the induction of labor (IoL) did not reduce this risk. Because the PPROMEXIL trial was underpowered and because of a lower-than-expected incidence of neonatal sepsis, we performed a second trial (PPROMEXIL-2), aiming to randomize 200 patients to improve the evidence in near-term PPROM.

STUDY DESIGN

In a nationwide multicenter study, nonlaboring women with PPROM between 34 and 37 weeks' gestational age were eligible for inclusion. Patients were randomized to IoL or expectant management (EM). The primary outcome measure was neonatal sepsis.

RESULTS

From December 2009 until January 2011, we randomized 100 women to IoL and 95 to EM. Neonatal sepsis was seen in 3 neonates (3.0%) in the IoL-group versus 4 neonates (4.1%) in the EM group (relative risk, 0.74; 95% confidence interval, 0.17-3.2). One of the sepsis cases in the IoL group resulted in neonatal death because of asphyxia. There were no significant differences in secondary outcomes.

CONCLUSION

The risk of neonatal sepsis after PPROM near term is low. Induction of labor does not reduce this risk.

Effects of intentional delivery on maternal and neonatal outcomes in pregnancies with preterm prelabour rupture of membranes between 28 and 34 weeks of gestation: a systematic review and meta-analysis

OBJECTIVE

To assess the effects of intentional delivery (ID) over expectant management (EM) in pregnancies complicated by preterm prelabour rupture of membranes (PPROM) between 28 and 34 weeks of gestation on maternal and neonatal outcomes.

METHODS

We searched Ovid MEDLINE, EMBASE, CINAHL, CENTRAL and Science Citation Index; contacted experts and checked reference lists of relevant studies. Studies were included if they were randomized controlled trials in all languages.

RESULTS

Five randomized trials were included and 488 subjects were analyzed. Overall, the results showed significant heterogeneity. Maternal infection as well as respiratory distress syndrome (RDS) & neonatal sepsis (NS) were not different between the two groups. Neonatal death, however, was significantly higher (risk ratio: 5.81; 95% CI: 1.35-25.08; p = 0.03) in the ID group after excluding studies that gave antenatal steroids. Incidence of cesarean section was significantly higher in the intentional delivery group, as well (risk ratio: 1.35; 95% CI: 1.02-1.80; p = 0.03).

CONCLUSION

Based on the available evidence, ID in pregnancies complicated with PPROM between 28 and 34 weeks carries some maternal and neonatal risks with no added benefits. Thus, this treatment should not be considered as an option for women with PPROM before 34 weeks of gestation in the absence of other indications for early delivery.

Prevalence and morbidity of late preterm infants: current status in a medical center of Northern Taiwan

BACKGROUND

"Late preterm" defines infants born at 34(0/7) through 36(6/7) weeks' gestation, which comprise a majority of preterm births. These infants were treated clinically as "near-term" in the past, but recent studies have implied increased morbidities that differentiate late preterm and term infants. The purpose of this study was to examine the prevalence and clinical complications that could be associated with late preterm birth, as compared to term.

METHODS

This was a retrospective cohort study that reviewed infants born in a medical center in Northern Taiwan during a 2-year period between 2008 and 2009. Maternal obstetrical factors, neonatal demographic distributions, and neonatal complications were compared between full-term and late preterm deliveries.

RESULTS

During the study period, there were 7998 live births in the institute, including 6507 term and 1491 preterm infants. Of the latter, there were 914 (61.3%) born after 34 weeks' gestation. The Neonatal Intensive Care Unit (NICU) (including a special care nursery) admission rate was higher in late preterm infants when compared to term (36% vs. 2%), and was 74%, 43%, and 21% in infants born at 34, 35, and 36 weeks' gestation, respectively. Compared with term infants, late-preterm infants had longer hospital stay if admitted to NICU (including special care nursery) (17 days vs. 10 days), and they were associated with increased risk of neonatal morbidities, including respiratory distress syndrome (2.6% vs. 0.02%), respiratory distress of other etiologies (16% vs. 2%), culture-proven sepsis (0.7% vs. 0.2%), hypoglycemia (3% vs. 0.4%), temperature instability (0.4% vs. 0.05%), feeding difficulty (2% vs. 0.4%), and hyperbilirubinemia needing phototherapy (14% vs. 3%). Late-preterm infants also had higher hospital readmission rate (4.4% vs. 2.3%, p<0.001) and neonatal mortality rate (0.3% vs. 0.08%, p=0.03).

CONCLUSION

Late-preterm infants have increased risk of neonatal morbidities associated with organ immaturity. The results of this study emphasize the importance of judicious obstetrical decision-making when considering late preterm delivery, and the need to set up anticipatory clinical guidelines for the care of late preterm infants.

Obstetric management of moderate and late preterm labour

Moderate and late preterm births account for the majority of preterm babies. The common perception that birth at 32-36 weeks' gestation carries few risks is now being challenged, as these babies have increased risk of neonatal mortality and morbidity. However, spontaneous labour at this gestation frequently has no specific, easily identifiable precursor, although preterm birth per se has a number of epidemiological and clinical associations. Prediction and prevention of preterm birth is currently largely aimed at identifying women at high risk such as those with previous preterm birth, and targeting intervention at this group. Both cervical length assessment and fibronectin testing permit some modification of the likelihood of preterm birth in this group. Progesterone treatment for the prevention of preterm birth is currently being researched widely, and appears a potentially promising strategy. Babies born at 32-36 weeks' gestation need careful monitoring in labour, with modification of intervention in labour due to their prematurity.

Induction of labor versus expectant management in women with preterm prelabor rupture of membranes between 34 and 37 weeks: a randomized controlled trial

BACKGROUND

At present, there is insufficient evidence to guide appropriate management of women with preterm prelabor rupture of membranes (PPROM) near term.

METHODS AND FINDINGS

We conducted an open-label randomized controlled trial in 60 hospitals in The Netherlands, which included non-laboring women with >24 h of PPROM between 34(+0) and 37(+0) wk of gestation. Participants were randomly allocated in a 1:1 ratio to induction of labor (IoL) or expectant management (EM) using block randomization. The main outcome was neonatal sepsis. Secondary outcomes included mode of delivery, respiratory distress syndrome (RDS), and chorioamnionitis. Patients and caregivers were not blinded to randomization status. We updated a prior meta-analysis on the effect of both interventions on neonatal sepsis, RDS, and cesarean section rate. From 1 January 2007 to 9 September 2009, 776 patients in 60 hospitals were eligible for the study, of which 536 patients were randomized. Four patients were excluded after randomization. We allocated 266 women (268 neonates) to IoL and 266 women (270 neonates) to EM. Neonatal sepsis occurred in seven (2.6%) newborns of women in the IoL group and in 11 (4.1%) neonates in the EM group (relative risk [RR] 0.64; 95% confidence interval [CI] 0.25 to 1.6). RDS was seen in 21 (7.8%, IoL) versus 17 neonates (6.3%, EM) (RR 1.3; 95% CI 0.67 to 2.3), and a cesarean section was performed in 36 (13%, IoL) versus 37 (14%, EM) women (RR 0.98; 95% CI 0.64 to 1.50). The risk for chorioamnionitis was reduced in the IoL group. No serious adverse events were reported. Updating an existing meta-analysis with our trial results (the only eligible trial for the update) indicated RRs of 1.06 (95% CI 0.64 to 1.76) for neonatal sepsis (eight trials, 1,230 neonates) and 1.27 (95% CI 0.98 to 1.65) for cesarean section (eight trials, 1,222 women) for IoL compared with EM.

CONCLUSIONS

In women whose pregnancy is complicated by late PPROM, neither our trial nor the updated meta-analysis indicates that IoL substantially improves pregnancy outcomes compared with EM.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN29313500

Proteomics mapping of cord blood identifies haptoglobin "switch-on" pattern as biomarker of early-onset neonatal sepsis in preterm newborns

Background

Intra-amniotic infection and/or inflammation (IAI) are important causes of preterm birth and early-onset neonatal sepsis (EONS). A prompt and accurate diagnosis of EONS is critical for improved neonatal outcomes. We sought to explore the cord blood proteome and identify biomarkers and functional protein networks characterizing EONS in preterm newborns.

Methodology/Principal Findings

We studied a prospective cohort of 180 premature newborns delivered May 2004-September 2009. A proteomics discovery phase employing two-dimensional differential gel electrophoresis (2D-DIGE) and mass spectrometry identified 19 differentially-expressed proteins in cord blood of newborns with culture-confirmed EONS (n = 3) versus GA-matched controls (n = 3). Ontological classifications of the proteins included transfer/carrier, immunity/defense, protease/extracellular matrix. The 1^st-level external validation conducted in the remaining 174 samples confirmed elevated haptoglobin and haptoglobin-related protein immunoreactivity (Hp&HpRP) in newborns with EONS (presumed and culture-confirmed) independent of GA at birth and birthweight (P<0.001). Western blot concurred in determining that EONS babies had conspicuous Hp&HpRP bands in cord blood (“switch-on pattern”) as opposed to non-EONS newborns who had near-absent “switch-off pattern” (P<0.001). Fetal Hp phenotype independently impacted Hp&HpRP. A Bayesian latent-class analysis (LCA) was further used for unbiased classification of all 180 cases based on probability of “antenatal IAI exposure” as latent variable. This was then subjected to 2^nd-level validation against indicators of adverse short-term neonatal outcome. The optimal LCA algorithm combined Hp&HpRP switch pattern (most input), interleukin-6 and neonatal hematological indices yielding two non-overlapping newborn clusters with low (≤20%) versus high (≥70%) probability of IAI exposure. This approach reclassified ∼30% of clinical EONS diagnoses lowering the number needed to harm and increasing the odds ratios for several adverse outcomes including intra-ventricular hemorrhage.

Conclusions/Significance

Antenatal exposure to IAI results in precocious switch-on of Hp&HpRP expression. As EONS biomarker, cord blood Hp&HpRP has potential to improve the selection of newborns for prompt and targeted treatment at birth.

Preterm premature rupture of membranes ≥ 32 weeks' gestation: impact of revised practice guidelines

OBJECTIVE

The purpose of this study was to determine the perinatal impact of the 2007 American College of Obstetricians and Gynecologists Practice Bulletin on preterm premature membrane rupture.

STUDY DESIGN

Perinatal outcomes were compared in women who had experienced preterm membrane rupture in the 3 years before the 2007 Practice Bulletin to similar women who experienced preterm premature rupture of membranes in the 3 years after the issue and implementation of the guideline.

RESULTS

After adjustment for gestational age at membrane rupture and steroids, composite severe morbidity (death, respiratory distress syndrome, assisted ventilation for ≥ 6 hours, sepsis, pneumonia, grade 3 or 4 intraventricular hemorrhage, or necrotizing enterocolitis) was similar by group. Infants in the "after" group experienced less pneumonia and sepsis, similar respiratory morbidity, but more labor inductions and postpartum hemorrhage.

CONCLUSION

The new guideline significantly decreases severe neonatal infections but is associated with more frequent labor induction and postpartum hemorrhage.

Morbidity and mortality in late preterm and early term newborns: a continuum

Late preterm and early term infants are at higher risk for short-term and long-term morbidities and mortality than term infants. Such outcomes are influenced by many factors, the strongest of which is gestational age. Counseling and educating women and families about risks of late preterm and early term births is helpful for timing and route of delivery, managing the pregnancy and infant, and prognosticating outcomes for infants.

Medically indicated--iatrogenic prematurity

Premature delivery of an infant is occasionally performed because of complications of pregnancy. This article reviews common medical indications for preterm delivery and the available evidence supporting delivery before 37 weeks of gestation. In many conditions, few data exist to guide optimal timing of delivery and management is guided by expert opinion. Ultimately, an individual assessment must be made in each case to weigh the risks that pregnancy continuation poses to the mother and/or fetus with the risks of prematurity and its associated morbidities.

Maternal markers for detecting early-onset neonatal infection and chorioamnionitis in cases of premature rupture of membranes at or after 34 weeks of gestation: a two-center prospective study

BACKGROUND

Accurate prediction of infection, including maternal chorioamnionitis and early-onset neonatal infection, remains a critical challenge in cases of preterm rupture of membranes and may influence obstetrical management. The aim of our study was to investigate the predictive value for early-onset neonatal infection and maternal histological and clinical chorioamnionitis of maternal biological markers in routine use at or after 34 weeks of gestation in women with premature rupture of membranes.

METHODS

We conducted a two-center prospective study of all women admitted for premature rupture of membranes at or after 34 weeks of gestation. The association of C-reactive protein, white blood cell count, vaginal sample bacteriological results, and a prediction model at admission, for early-onset neonatal infection and maternal chorioamnionitis were analyzed by comparing areas under the receiver operating characteristic curves and specificity.

RESULTS

The study included 399 women. In all, 4.3% of the newborns had an early-onset neonatal infection and 5.3% of the women had clinical chorioamnionitis. Histological chorioamnionitis was detected on 10.8% of 297 placentas tested. White blood cell counts and C-reactive protein concentrations were significantly associated with early-onset neonatal infection and included in a prediction model. The area under the receiver operating characteristic curve of this model was 0.82 (95% CI [0.72, 0.92]) and of C-reactive protein, 0.80 (95% CI [0.68, 0.92]) (p = 1.0). Specificity was significantly higher for C-reactive protein than for the prediction model (48% and 43% respectively, p < 0.05). C-reactive protein was associated with clinical and histological chorioamnionitis, with areas under the receiver operating characteristic curve of 0.61 (95% CI [0.48, 0.74]) and 0.62 (95% CI [0.47, 0.74]), respectively.

CONCLUSIONS

The concentration of C-reactive protein at admission for premature rupture of membranes is the most accurate infectious marker for prediction of early-onset neonatal infection in routine use with a sensitivity > 90%. A useful next step would be a randomized prospective study of management strategy comparing CRP at admission with active management to assess whether this more individualized care is a safe alternative strategy in women with premature rupture of membranes at or after 34 weeks.

Optimal time for delivery with preterm premature rupture of membranes from 32 to 36 6/7 weeks

OBJECTIVE

To evaluate the optimal time for delivery in singleton pregnancies with preterm premature rupture of membranes (PPROM) when delivered between 32 and 36 6/7 weeks gestational age (GA).

STUDY DESIGN

We performed a retrospective cohort study of all singleton pregnancies with PPROM who delivered between 32 and 36 6/7 weeks gestation at our institution. We matched the delivery and NICU datasets to determine composite morbidity (COMP MORB) and NICU length of stay (LOS) stratified by weeks of gestation. COMP MORB was defined as one or more of: bronchopulmonary dysplasia, respiratory distress syndrome, necrotizing entercolitis, intraventricular hemorrhage, dissiminated intravascular coagulation, and culture proven sepsis. We used χ² and student 't' test as appropriate and a receiver operating characteristc curve (ROC).

RESULTS

There were 195 newborns with PPROM with a range of 30 babies at 36 weeks to a high of 53 at 34 weeks. The mean (± SD) NICU LOS was 22.5 (± 9.9) days at 32 weeks, 17.8 (± 10.0) days at 33 weeks, 14.8 (± 11.0) days at 34 weeks, 4.5 (± 4.7) days at 35 weeks, and 1.5 (± 4.4) days at 36 weeks (p < 0.0001). There was no difference in duration of ROM by GA with a range of 6.8 to 1.9 by week (p = NS). The ROC curve had a cut point for COMP MORB at 34.1 weeks GA (sens = 95%, FPR 48.6%, area under curve 0.782, p = 0.0002).

CONCLUSION

Our study suggests that delivery of PPROM pregnancies at 34.1 weeks GA avoids 95% of composite morbidity, and delivery after 35 weeks GA will decrease the NICU LOS.

Obstetrical intervention and the singleton preterm birth rate in the United States from 1991-2006

OBJECTIVES

We examined the relationship between obstetrical intervention and preterm birth in the United States between 1991 and 2006.

METHODS

We assessed changes in preterm birth, cesarean delivery, labor induction, and associated risks. Logistic regression modeled the odds of preterm obstetrical intervention after risk adjustment.

RESULTS

From 1991 to 2006, the percentage of singleton preterm births increased 13%. The cesarean delivery rate for singleton preterm births increased 47%, and the rate of induced labor doubled. In 2006, 51% of singleton preterm births were spontaneous vaginal deliveries, compared with 69% in 1991. After adjustment for demographic and medical risks, the mother of a preterm infant was 88% (95% confidence interval [CI] = 1.87, 1.90) more likely to have an obstetrical intervention in 2006 than in 1991. Using new birth certificate data from 19 states, we estimated that 42% of singleton preterm infants were delivered via induction or cesarean birth without spontaneous onset of labor.

CONCLUSIONS

Obstetrical interventions were related to the increase in the US preterm birth rate between 1991 and 2006. The public health community can play a central role in reducing medically unnecessary interventions.