Preterm premature rupture of the membranes: diagnosis and management

Previable preterm premature rupture of membranes: 117 cases with neonatal outcomes in light of current research

BACKGROUND

ppPROM <  24 + 0 weeks of gestation complicates <  1 % of all pregnancies but is responsible for significant maternal and neonatal morbidity. It is associated with 18-20% of perinatal deaths.

OBJECTIVE

To evaluate neonatal outcome after expectant management in ppPROM in order to obtain evidence-based information for purposes of future counselling.

METHODS

A single-centre, retrospective cohort study of 117 neonates born 1994 to 2012 after ppPROM <  24 weeks of gestation with a latency period >  24 hours and admission to the NICU of the Department of Neonatology, University of Bonn. Data of pregnancy characteristics and neonatal outcome were collected. The results were compared to those found in the literature.

RESULTS

The mean gestational age at ppPROM was 20.45±2,9 weeks (range 11 + 2 -22 + 6) with a mean latency period of 44.7±34.8 days (range 1-135). Mean gestational age at birth was 26.77±3.22 weeks (range 22 + 2-35 + 3). 117 newborns were admitted to the NICU, the overall survival rate at discharge was 72.6% (85/117). Non-survivors had a significantly lower gestational age and higher rates of intra-amniotic infections. The most common neonatal morbidities were RDS (76.1%), BPD (22.2%), pulmonary hypoplasia (PH) (14.5%), neonatal sepsis (37.6%), IVH (34.1% all grades, 17.9% grades III/IV), NEC (8.5%) and musculoskeletal deformities (13.7%). Mild growth restriction as a new complication of ppPROM was observed.

CONCLUSIONS

Neonatal morbidity after expectant management is similar to that described for infants without ppPROM, but carries a higher risk of pulmonary hypoplasia and mild growth restriction.

Directive clinique no 430 : Diagnostic et prise en charge de la rupture prématurée des membranes avant terme

OBJECTIF

Fournir des directives claires et concises pour le diagnostic et la prise en charge de la rupture prématurée des membranes avant terme (RPMAT).

POPULATION CIBLE

Toute patiente manifestant une rupture prématurée des membranes avant 37 semaines d'aménorrhée. BéNéFICES, RISQUES ET COûTS: La présente directive clinique vise à fournir les premières recommandations générales canadiennes sur la prise en charge de la rupture des membranes avant terme. Elle repose sur un examen complet et à jour des données probantes sur le diagnostic de la rupture et sur la prise en charge, le bon moment et les modes d'accouchement. DONNéES PROBANTES: Des recherches ont été effectuées dans PubMed-Medline et Cochrane en 2021 en utilisant les termes suivants : preterm premature rupture of membranes, PPROM, chorioamnionitis, Nitrazine test, ferning, commercial tests, PAMG-1, IGFBP-1 test, ultrasonography, PPROM/antenatal corticosteroids, PPROM/Magnesium sulphate, PPROM/antibiotic treatment, PPROM/tocolysis, PPROM/preterm labour, PPROM/neonatal outcomes, PPROM/mortality, PPROM/outpatient/inpatient, PPROM/cerclage, previable PPROM. Les articles retenus sont des essais cliniques randomisés, des méta-analyses, des revues systématiques, des directives cliniques et des études observationnelles. D'autres publications pertinentes ont été sélectionnées à partir des notices bibliographiques de ces articles. Seuls les articles en anglais ont été examinés. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Voir l'annexe A (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et faibles). PROFESSIONNELS CONCERNéS: Tous les fournisseurs de soins de santé prénatale ou périnatale. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

Guideline No. 430: Diagnosis and management of preterm prelabour rupture of membranes

OBJECTIVE

To provide clear and concise guidelines for the diagnosis and management of preterm prelabour rupture of membranes (PPROM) TARGET POPULATION: All patients with PPROM <37 weeks gestation BENEFITS, HARMS, AND COSTS: This guideline aims to provide the first Canadian general guideline on the management of preterm membrane rupture. It includes a comprehensive and up-to-date review of the evidence on the diagnosis, management, timing and method of delivery.

EVIDENCE

The following search terms were entered into PubMed/Medline and Cochrane in 2021: preterm premature rupture of membranes, PPROM, chorioamnionitis, Nitrazine test, ferning, commercial tests, placental alpha microglobulin-1 (PAMG-1) test, insulin-like growth factor-binding protein-1 (IGFBP-1) test, ultrasonography, PPROM/antenatal corticosteroids, PPROM/Magnesium sulphate, PPROM/ antibiotic treatment, PPROM/tocolysis, PPROM/preterm labour, PPROM/Neonatal outcomes, PPROM/mortality, PPROM/outpatient/inpatient, PPROM/cerclage, previable PPROM. Articles included were randomized controlled trials, meta-analyses, systematic reviews, guidelines, and observational studies. Additional publications were identified from the bibliographies of these articles. Only English-language articles were reviewed.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

All prenatal and perinatal health care providers.

SUMMARY STATEMENTS

RECOMMENDATIONS.

A Data Mining Approach Reveals Chemicals Detected at Higher Levels in Non-Hispanic Black Women Target Preterm Birth Genes and Pathways

Preterm birth occurs disproportionately in the USA non-Hispanic Black population. Black women also face disproportionate exposure to certain environmental chemicals. The goal of this study was to use publicly available toxicogenomic data to identify chemical exposures that may contribute to preterm birth disparities. We tested 19 chemicals observed at higher levels in the blood or urine of non-Hispanic Black women compared to non-Hispanic White women. We obtained chemical-gene interactions from the Comparative Toxicogenomics Database and a list of genes involved in preterm birth from the Preterm Birth Database. We tested chemicals for enrichment with preterm birth genes using chi-squared tests. We then conducted pathway enrichment analysis for the preterm birth genes using DAVID software and identified chemical impacts on genes involved in these pathways. Genes annotated to all 19 chemicals were enriched with preterm birth genes (FDR-adjusted p value < 0.05). Preterm birth enriched chemicals that were detected at the highest levels in non-Hispanic Black women included methyl mercury, methylparaben, propylparaben, diethyl phthalate, dichlorodiphenyldichloroethylene, and bisphenol S. The preterm birth genes were enriched for pathways including "inflammatory response" (FDR-adjusted p value = 3 × 10-19), "aging" (FDR-adjusted p value = 4 × 10-8) and "response to estradiol" (FDR-adjusted p value = 2 × 10-4). Chemicals enriched with preterm birth genes impacted genes in all three pathways. This study adds to the body of knowledge suggesting that exposures to environmental chemicals contribute to racial disparities in preterm birth and that multiple chemicals drive these effects. These chemicals affect genes involved in biological processes relevant to preterm birth such as inflammation, aging, and estradiol pathways.

The Association between Shirodkar Cerclage and Preterm Premature Rupture of Membranes in Singleton Pregnancies

OBJECTIVE

The aim of this study was to estimate if preterm premature rupture of membranes in women with cerclage is due to the cerclage itself or rather the underlying risk factors for preterm birth in this population.

STUDY DESIGN

This was a retrospective cohort study of singleton pregnancies who underwent Shirodkar cerclage by a single maternal-fetal medicine practice between 2005 and 2019. The control group was an equal number of randomly selected women with a singleton gestation who had a prior preterm birth and were treated with 17-OH-progesterone but no cerclage. Patients with major uterine anomalies or fetal anomalies were excluded. The primary outcome was preterm premature rupture of membranes prior to 34 weeks. Chi-square and logistic regression were used.

RESULTS

A total of 350 women with cerclage (154 [44%] history-indicated, 137 [39%] ultrasound-indicated, and 59 [17%] exam-indicated) and 350 controls were included. Preterm premature rupture of membranes prior to 34 weeks did not differ between the groups (8.9% in cerclage vs. 6.0% in controls, p = 0.149, adjusted odds ratio 0.62, 95% confidence interval: 0.24-1.64) nor between the different cerclage indications (9.1% of history-indicated, 7.3% of ultrasound-indicated, and 11.9% of exam-indicated, p = 0.582). This study had 80% power with an α error of 0.05 to detect an increase in preterm premature rupture of membranes prior to 34 weeks from 6.0% in the control group to 12.0% in the cerclage group.

CONCLUSION

Cerclage does not increase the risk of preterm premature rupture of membranes prior to 34 weeks compared with other women at increased risk of preterm birth. The observed association between cerclage and preterm premature rupture of membranes is likely due to underlying risk factors and not the cerclage itself. The risk of preterm premature rupture of membranes prior to 34 weeks in women with cerclage is 10% or less and does not appear to differ based on cerclage indication.

KEY POINTS

· Cerclage does not increase the risk of PPROM.. · Risk of PPROM with cerclage is approximately 10%.. · Risk does not appear to vary by indication..

Mechanism of Human Fetal Membrane Biomechanical Weakening, Rupture and Potential Targets for Therapeutic Intervention

Using a novel in vitro model system combining biochemical/histologic with bioengineering approaches has provided significant insights into the physiology of fetal membrane weakening and rupture along with potential mechanistic reasons for lack of efficacy of currently clinically used agents to prevent preterm premature rupture of the membranes (pPROM) and preterm births. Likewise, the model has also facilitated screening of agents with potential for preventing pPROM and preterm birth.

Inflammation-related downregulation of zonula Occludens-1 in fetal membrane contributes to development of prelabor rupture of membranes

INTRODUCTION

The aim of this research was to study the alteration of three key tight junction proteins, to explore whether they were involved in the occurrence of prelabor rupture of the membrane (PROM) and to determine the correlation with intrauterine infection.

METHODS

A total of 208 women were enrolled between January 2015 to December 2018, including those with preterm and term PROM (PROM group) and normal pregnancies with intact fetal membrane (control group). We investigated the expressions of three key TJ molecules (Zonula occludens-1, Occludin and Claudin-5) in fetal membranes. The localization and expression of Zonula occludens-1 (ZO-1) in the amnion and chorion were studied by immunohistochemistry assay. The associations between ZO-1 expression levels and extent of inflammatory reactions as well as other obstetric characteristics were further studied using Spearman's rank correlation test and Mann-Whitney U test.

RESULTS

ZO-1 was significantly downregulated in PROM group compared with control group (P < 0.001), whereas no significant changes were found for Occludin and Claudin-5. ZO-1 expression was reduced in the chorion and amnion layers in PROM group compared with that in control group, which showed a significant difference (P < 0.01), but no significant differences were observed between the preterm PROM and term PROM groups (P > 0.05). The expression levels of ZO-1 in the chorion were negatively correlated with the stage/grade of acute chorioamnionitis (P < 0.05).

DISCUSSION

Our study suggests that inflammation-related downregulation of ZO-1 might be a pivotal event in the occurrence of PROM, which helps to clarify the mechanism of membrane rupture caused by infection.

Toxicant Disruption of Immune Defenses: Potential Implications for Fetal Membranes and Pregnancy

In addition to providing a physical compartment for gestation, the fetal membranes (FM) are an active immunological barrier that provides defense against pathogenic microorganisms that ascend the gravid reproductive tract. Pathogenic infection of the gestational tissues (FM and placenta) is a leading known cause of preterm birth (PTB). Some environmental toxicants decrease the capacity for organisms to mount an immune defense against pathogens. For example, the immunosuppressive effects of the widespread environmental contaminant trichloroethylene (TCE) are documented for lung infection with Streptococcus zooepidemicus. Group B Streptococcus (GBS; Streptococcus agalactiae) is a bacterial pathogen that is frequently found in the female reproductive tract and can colonize the FM in pregnant women. Work in our laboratory has demonstrated that a bioactive TCE metabolite, S-(1, 2-dichlorovinyl)-L-cysteine (DCVC), potently inhibits innate immune responses to GBS in human FM in culture. Despite these provocative findings, little is known about how DCVC and other toxicants modify the risk for pathogenic infection of FM. Infection of the gestational tissues (FM and placenta) is a leading known cause of PTB, therefore toxicant compromise of FM ability to fight off infectious microorganisms could significantly contribute to PTB risk. This Perspective provides the current status of understanding of toxicant-pathogen interactions in FM, highlighting knowledge gaps, challenges, and opportunities for research that can advance protections for maternal and fetal health.

Neonatal outcomes following previable prelabour rupture of membranes before 23 weeks of gestation - A retrospective cohort study

OBJECTIVE

To compare outcomes of hospitalized preterm infants following previable prelabour rupture of membranes (PPROM) at≤23 weeks of gestation.

METHODS

Retrospective cohort study of preterm infants admitted for intensive care, between January 2006 and December 2016 following PPROM, was conducted. Short term clinical outcomes included severity of respiratory morbidity, length of hospital stay and mortality. Neurodevelopment in survivors was assessed using Bayley's Scales of Infant Development (3rd edition) at 24 months corrected age.

RESULTS

A total of 82 preterm infants were admitted following PPROM at < 23 weeks and were grouped as: Group 1 (n = 28) with PPROM < 20 weeks and Group 2 (n = 54) with PPROM between 20-22 + 6 weeks. Median latency following PPROM was significantly longer in Group 1 infants [69(Interquartile range (IQR): 43-74; Range (R): 25-100 vs. 29(IQR: 10-53; R: 2-72) days, p < 0.001]. Median gestation at delivery was 27.4 weeks (Group 1) vs. 25.1 weeks (Group 2). Group 1 had a significantly higher incidence of oligohydramnios [13(46.4%) vs. 8(14.8%), p = 0.002], lower Apgar scores (<7) at 5 minutes [19(67.9%) vs. 24(44.4%), p = 0.044], increased pulmonary hypoplasia [13(46.4%) vs. 5(9.3%), p < 0.001], joint contractures [3(10.7%) vs. 0, p = 0.037] and mortality [10(35.7%) vs. 7(13.0%), p = 0.016]. Neurodevelopmental outcomes at 24 months corrected age were comparable in the 36 surviving infants (9/18 vs. 27/547).

CONCLUSION

Morbidity and mortality is high in infants born after previable PPROM; specifically, in those with PPROM < 20 weeks although early childhood neurodevelopmental outcomes were comparable. Larger prospective studies focussing on long term neonatal outcomes are needed to confirm these findings.

Regulatory B Cells Are Decreased and Impaired in Their Function in Peripheral Maternal Blood in Pre-term Birth

Preterm birth (PTB) is defined as birth before 37 completed weeks of gestation. The causes of PTB are multiple and complex, the underlying pathophysiology being largely unknown. Interferences in the fine-tuned balance of the maternal immune system have been pointed to as one possible cause of PTB. Regulatory B cells (Breg) are part of the adaptive immune response, and recent data suggest that they may contribute to a healthy pregnancy by their regulatory/suppressive function. We investigated the frequency of Breg cells in peripheral blood of women undergoing PTB and control women immediately before giving birth via cesarean section. We detected an enhanced number of B cells, but a reduced number of Breg cells in women delivering preterm. In addition, the percentage of IL-10-producing B cells was decreased in PTB following stimulation with TLR agonists CpG or LPS, alone or combined with CD40L. This was associated with increased levels of pro-inflammatory cytokines in maternal serum. Moreover, isolated maternal B cells before delivering premature babies secreted higher level of the pro-inflammatory cytokine IL-6. No alterations in the frequency of regulatory T cells were found. Our data indicate that alterations in the number and function of Breg cells in peripheral maternal blood contribute to the immunological changes observed in preterm delivery and suggest these cells as important regulators of maternal immune responses.

Comparison of the accuracy and reliability of the AmniSure, AMNIOQUICK, and AL-SENSE tests for early diagnosis of premature rupture of membranes

OBJECTIVE

To compare the accuracy and reliability of the AmniSure, AMNIOQUICK, and AL-SENSE tests with conventional tests to diagnose suspected premature rupture of membranes (PROM).

METHODS

A prospective cohort study of 60 pregnant women at 25-36 weeks of pregnancy with suspected PROM was conducted between January and April 2015. AmniSure (Qiagen Sciences LLC, Germantown, MD, USA), AMNIOQUICK (BIOSYNEX, Strasbourg, France), and AL-SENSE (Common Sense Ltd, Caesarea, Israel) tests were performed after conventional tests (ultrasonography, pooling, nitrazine, and fern tests) and women were followed-up for 7 days. Sensitivity, specificity, and diagnostic accuracy, among others, were assessed and compared.

RESULTS

For women with a confirmed diagnosis of PROM, the sensitivity and specificity of conventional tests were 93.7% and 100.0%, respectively; diagnostic accuracy was 98.3%. Sensitivity, specificity, and diagnostic accuracy were all 100.0% for AmniSure. Sensitivity, specificity, and diagnostic accuracy for AMNIOQUICK were 75.0%, 97.7%, and 91.6%, respectively. Sensitivity, specificity, and diagnostic accuracy were 75.0%, 86.3%, 83.3%, respectively, for the AL-SENSE pad test.

CONCLUSION

The AmniSure test was most sensitive and specific for diagnosing PROM compared with the other tests and is reliable and usable.

Fetal Membranes, Not a Mere Appendage of the Placenta, but a Critical Part of the Fetal-Maternal Interface Controlling Parturition

Fetal membranes (FMs) play a role in pregnancy maintenance and promoting parturition at term. The FMs are not just part of the placenta, structurally or functionally. Although attached to the placenta, the amnion has a separate embryologic origin, and the chorion deviates from the placenta by the first month of pregnancy. Other than immune protection, these FM functions are not those of the placenta. FM dysfunction is associated with and may cause adverse pregnancy outcomes. Ongoing research may identify biomarkers for pending preterm premature rupture of the FMs as well as therapeutic agents, to prevent it and resulting preterm birth.

Late preterm: a new high risk group in neonatology

Late preterm infants are those infants born between 34 0/7 weeks through 36 6/7 week of gestation. These are physiologically less mature and have limited compensatory responses to the extrauterine environment compared with term infants. Despite their increased risk for morbidity and mortality, late preterm newborns are often cared in the well-baby nurseries of hospital after birth and are discharged from the hospital by 2-3 days of postnatal age. They are usually treated like developmentally mature term infants because many of them are of same birth weight and same size as term infants. There is a steady increase in the late preterm birth rate in last decade because of either maternal, fetal, or placental/uterine causes. There has been shift in the distribution of births from term and post-term toward earlier gestations. Although late preterm infants are the largest subgroup of preterm infants, there has been little research on this group until recently. This is mainly because of labeling them as "near-term". Such infants were being looked upon as "almost mature", and were thought as neonate requiring either no or minimal concern. In the obstetric and pediatric practice, late preterm infants are often considered functionally and developmentally mature and often managed by protocols developed for full-term infants. Thus, limited efforts are taken to prolong pregnancy in cases of preterm labor beyond 34 weeks, moreover after 34 weeks most centers do not administer antenatal prophylactic steroids. These practices are based on previous studies reporting neonatal mortality and morbidity in the late preterm period to be only slightly higher in comparison with term infants and whereas in the current scenario the difference is significant. Late preterm infants have 2-3-fold increased risk of morbidities such as hypothermia, hypoglycemia, delayed lung fluid clearance, respiratory distress, poor feeding, jaundice, sepsis, and readmission rates after initial hospital discharge. This leads to huge impact on the overall health care resources. In this review, we cover various aspects of these late preterm infants like etiology, immediate and long-term outcome.

Cervical human papillomavirus infection in women with preterm prelabor rupture of membranes

OBJECTIVE

To evaluate the association between cervical human papillomavirus (HPV) infection at the time of admission and the presence of microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation (IAI) in women with preterm prelabor rupture of membranes (PPROM) and to determine the association between cervical HPV infection and short-term neonatal morbidity.

METHODS

One hundred women with singleton pregnancies complicated by PPROM between the gestational ages of 24+0 and 36+6 weeks were included in the study. The presence of HPV DNA was evaluated in scraped cervical cells using polymerase chain reaction (PCR). Amniotic fluid samples were obtained by transabdominal amniocentesis.

RESULTS

The rate of cervical HPV infection in women with PPROM was 24%. The rates of MIAC and IAI were not different between women with cervical HPV infection and those without cervical HPV infection [MIAC: with HPV: 21% (5/24) vs. without HPV: 22% (17/76), p = 1.00; IAI: with HPV: 21% (5/24) vs. without HPV: 18% (14/76), p = 0.77]. There were no differences in the selected aspects of short-term neonatal morbidity between women with and without cervical HPV infection.

CONCLUSIONS

In women with PPROM, the presence of cervical HPV infection at the time of admission is not related to a higher risk of intra-amniotic infection-related and inflammatory complications or worse short-term neonatal outcomes.

A Bayesian Stepwise Discriminant Model for Predicting Risk Factors of Preterm Premature Rupture of Membranes: A Case-control Study

BACKGROUND

Preterm premature rupture of membrane (PPROM) can lead to serious consequences such as intrauterine infection, prolapse of the umbilical cord, and neonatal respiratory distress syndrome. Genital infection is a very important risk which closely related with PPROM. The preliminary study only made qualitative research on genital infection, but there was no deep and clear judgment about the effects of pathogenic bacteria. This study was to analyze the association of infections with PPROM in pregnant women in Shaanxi, China, and to establish Bayesian stepwise discriminant analysis to predict the incidence of PPROM.

METHODS

In training group, the 112 pregnant women with PPROM were enrolled in the case subgroup, and 108 normal pregnant women in the control subgroup using an unmatched case-control method. The sociodemographic characteristics of these participants were collected by face-to-face interviews. Vaginal excretions from each participant were sampled at 28-36+6 weeks of pregnancy using a sterile swab. DNA corresponding to Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU), Candida albicans, group B streptococci (GBS), herpes simplex virus-1 (HSV-1), and HSV-2 were detected in each participant by real-time polymerase chain reaction. A model of Bayesian discriminant analysis was established and then verified by a multicenter validation group that included 500 participants in the case subgroup and 500 participants in the control subgroup from five different hospitals in the Shaanxi province, respectively.

RESULTS

The sociological characteristics were not significantly different between the case and control subgroups in both training and validation groups (all P > 0.05). In training group, the infection rates of UU (11.6% vs. 3.7%), CT (17.0% vs. 5.6%), and GBS (22.3% vs. 6.5%) showed statistically different between the case and control subgroups (all P < 0.05), log-transformed quantification of UU, CT, GBS, and HSV-2 showed statistically different between the case and control subgroups (P < 0.05). All etiological agents were introduced into the Bayesian stepwise discriminant model showed that UU, CT, and GBS infections were the main contributors to PPROM, with coefficients of 0.441, 3.347, and 4.126, respectively. The accuracy rates of the Bayesian stepwise discriminant analysis between the case and control subgroup were 84.1% and 86.8% in the training and validation groups, respectively.

CONCLUSIONS

This study established a Bayesian stepwise discriminant model to predict the incidence of PPROM. The UU, CT, and GBS infections were discriminant factors for PPROM according to a Bayesian stepwise discriminant analysis. This model could provide a new method for the early predicting of PPROM in pregnant women.

Late preterm prelabor rupture of fetal membranes: fetal inflammatory response and neonatal outcome

BackgroundTo characterize the influence of microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI) on the intensity of the fetal inflammatory response and the association between the presence of the fetal inflammatory response syndrome (FIRS) and short-term neonatal morbidity in the preterm prelabor rupture of membranes (PPROM) between the gestational ages of 34 and 37 weeks.MethodsOne hundred and fifty-nine women were included in the study. The umbilical cord blood interleukin (IL)-6 concentrations were determined using enzyme-linked immunosorbent assay kits. FIRS was defined based on the umbilical cord blood IL-6 concentration and the presence of funisitis and/or chorionic plate vasculitis.ResultsWomen with both MIAC and IAI had the highest median umbilical cord blood IL-6 concentrations and highest rates of FIRS. Women with FIRS had the higher rates of early-onset sepsis and intraventricular hemorrhage grades I and II when FIRS was characterized based on the umbilical cord blood IL-6 concentrations and the histopathological findings.ConclusionThe presence of both MIAC and IAI was associated with a higher fetal inflammatory response and a higher rate of FIRS. Different aspects of short-term neonatal morbidity were related to FIRS when defined by umbilical cord blood IL-6 concentrations and the histopathology of the placenta.

Inflammatory and vascular placental lesions are associated with neonatal amplitude integrated EEG recording in early premature neonates

INTRODUCTION

Placental histologic examination can assist in revealing the mechanism leading to preterm birth. Accumulating evidence suggests an association between intrauterine pathological processes, morbidity and mortality of premature infants, and their long term outcome. Neonatal brain activity is increasingly monitored in neonatal intensive care units by amplitude integrated EEG (aEEG) and indices of background activity and sleep cycling patterns were correlated with long term outcome. We hypothesized an association between types of placental lesions and abnormal neonatal aEEG patterns.

OBJECTIVE

To determine the association between the placental lesions observed in extreme preterm deliveries, and their neonatal aEEG patterns and survival.

PATIENTS AND METHODS

This prospective cohort study included extreme premature infants, who were born ≤ 28 weeks of gestation, their placentas were available for histologic examination, and had a continues aEEG, soon after birth)n = 34). Infants and maternal clinical data were collected. aEEG data was assessed for percentage of depressed daily activity in the first 3 days of life and for sleep cycling. Associations of placental histology with clinical findings and aEEG activity were explored using parametric and non-parametric statistics.

RESULTS

Twenty two out of the 34 newborns survived to discharge. Preterm prelabor rupture of membranes (PPROM) or chorioamnionitis were associated with placental lesions consistent with fetal amniotic fluid infection (AFI) or maternal under perfusion (MUP) (P < 0.05). Lesions consistent with fetal response to AFI were associated with absence of SWC pattern during the 1st day of life. Fetal-vascular-thrombo-occlusive lesions of inflammatory type were negatively associated with depressed cerebral activity during the 1st day of life, and with aEEG cycling during the 2nd day of life (P<0.05). Placental lesions associated with MUP were associated with depressed neonatal cerebral activity during the first 3 days of life (P = 0.007).

CONCLUSIONS

Depressed neonatal aEEG patterns are associated with placental lesions consistent with maternal under perfusion, and amniotic fluid infection of fetal type, but not with fetal thrombo-oclusive vascular disease of inflammatory type. Our findings highlight the association between the intrauterine mechanisms leading to preterm parturition and subsequent depressed neonatal cerebral function early after birth, which eventually may put premature infants at risk for abnormal neurodevelopmental outcome.

Preterm infant outcomes in relation to the gestational age of onset and duration of prelabour rupture of membranes: a retrospective cohort study

OBJECTIVE

To determine the hospital outcomes of liveborn infants at 23-31 weeks following prelabour preterm rupture of membranes (PPROM).

METHOD

A regional retrospective cohort study of 4454 infants of 23-31 weeks' gestation admitted to a tertiary neonatal network between 2007 and 2011. Primary outcome was the composite chronic lung disease (CLD) or mortality at discharge.

RESULTS

225 (5%) neonates had a history of PPROM occurring prior to 24⁺⁰ weeks (Early-PPROM), 829 (19%) had a history of PPROM at or after 24⁺⁰ weeks' gestation (Late-PPROM) and 3400 (76%) had no history of PPROM (No-PPROM). In comparison to No-PPROM, Early-PPROM group had higher CLD/mortality in infants born at 23-27 weeks (OR 1.95; 95% CI 1.34 to 2.85) and 28-31 weeks (OR 4.98; 95% CI 2.99 to 8.28). Within Early-PPROM group, the latency of PPROM >14 days had lower CLD/mortality in comparison to latency ≤14 days (57.6% vs 77%, OR 0.40; 95% CI 0.21 to 0.76). Late-PPROM group had significantly lower CLD/mortality in comparison to No-PPROM group at 23-27 weeks (OR 0.50; 95% CI 0.37 to 0.69) and 28-31 weeks (OR 0.50; 95% CI 0.36 to 0.71). Within Late-PPROM group, latency >14 days was associated with an increased CLD/mortality in 28-31 weeks (14.1% vs 5.4%, OR 2.88; 95% CI 1.31 to 6.38).

CONCLUSIONS

Early-PPROM prior to 24 weeks' gestation had high incidence of CLD/mortality even after correcting for gestational age. Late-PPROM at or after 24 weeks had lower CLD/mortality compared with No-PPROM. Latency >14 days in Late-PPROM group at 28-31 week group increased the odds of CLD/mortality.

ADAMTS4 and Oxidative/Antioxidative Status in Preterm Premature Rupture of Membranes

AIM

To determine the function of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS4), total oxidant status (TOS), total antioxidant status (TAS), and aryl esterase (ARES) in preterm premature rupture of membranes (PPROM) and to investigate the association with premature rupture of membranes (PROMs).

MATERIAL AND METHODS

58 pregnant women were included in this prospective study which comprised 29 PPROM patients as the study group and 29 patients, having healthy amniotic membranes, as the control group. ADAMTS4, TAS, TOS, and ARES levels were studied in the amniotic membrane homogenates of the patients.

RESULTS

ADAMTS4, TAS TOS, and ARES levels of amniotic membrane lysates were significantly different between PPROM and control groups (p < 0.001, p < 0.001, p = 0.008 and p = 0.002, respectively). Increased amniotic membrane ADAMTS4 (OR: 1.051 95% CI 1.006-1.098, p = 0.024) and TOS (OR: 12.777 95% CI 1.595-102.323, p = 0.016) were found to be significantly associated with the increased risk of PPROM.

CONCLUSION

ADAMTS4, TOS, and ARES levels were higher and TAS level was lower in PPROM patients than the normal healthy control group which had healthy amniotic membranes at term. As a result, ADAMTS4 may have a role in the pathogenesis by causing increased oxidative and inflammatory environment in PPROM.

Repairing Fetal Membranes with a Self-adhesive Ultrathin Polymeric Film: Evaluation in Mid-gestational Rabbit Model

Preterm premature rupture of membranes causes 40% of all preterm births, affecting 150000 women each year in the United States. Prenatal diagnostic procedures and surgical interventions increase incidence of adverse events, leading to iatrogenic membrane rupture after a fetoscopic procedure in 45% of cases. We propose an ultrathin, self-adherent, poly-L-lactic acid patch ("nanofilm") as a reparative wound closure after endoscopic/fetoscopic procedures. These nanofilms are compatible with application in wet conditions and with minimally invasive instrumentation. Ex vivo studies to evaluate the nanofilm were conducted using human chorion-amnion (CA) membranes. A custom-built inflation device was used for mechanical characterization of CA membranes and for assessment of nanofilm adhesion and sealing of membrane defects up to 3 mm in size. These ex vivo tests demonstrated the ability of the nanofilm to seal human CA defects ranging in size from 1 to 3 mm in diameter. In vivo survival studies were conducted in 25 mid-gestational rabbits, defects were created by perforating the uterus and the CA membranes and subsequently using the nanofilm to seal these wounds. These in vivo studies confirmed the successful sealing of defects smaller than 3 mm observed ex vivo. Histological analysis of whole harvested uteri 7 days after surgery showed intact uterine walls in 59% of the nanofilm repaired fetuses, along with increased uterine size and intrauterine development in 63% of the cases. In summary, we have developed an ultrathin, self-adhesive nanofilm for repair of uterine membrane defects.

Ascorbic Acid concentration and preterm premature rupture of membranes

INTRODUCTION

Preterm premature rupture of membranes (PPROM) complicates 1-5 % of all pregnancies and is the major contributory factor for perinatal morbidity and mortality. Micronutrient deficiency (vitamin C) is associated with increased risk of PPROM. This study was conducted to establish the association between maternal plasma vitamin C concentration in women with PPROM and women without PPROM and to study the difference in maternal morbidity, neonatal morbidity, and mortality.

METHODS

A prospective study was conducted where 40 women (20 in each study and control group) with singleton pregnancies between 28 and 37 weeks gestation were recruited. Women with anemia, diabetes, UTI, RTI, vaginal infection, bleeding, h/o PPROM in previous pregnancy, polyhydramnios, and smoker were excluded from the study. Maternal plasma vitamin C levels were measured.

RESULTS

Ascorbic acid levels were low in women with PPROM 0.41 ± 0.08 versus 0.84 ± 0.19 mg/dl. There is a linear decline in plasma vitamin C levels as the pregnancy advances. Inverse relationship was observed between duration of rupture of membranes and vitamin C levels. There was a significant difference in maternal morbidity, neonatal morbidity, and mortality.

CONCLUSION

Ascorbic acid concentration was low in women with PPROM. Thus, vitamin C supplementation should be made mandatory along with iron and calcium to antenatal women to avoid the complications of PPROM.

Early elevations of the complement activation fragment C3a and adverse pregnancy outcomes

OBJECTIVE

To estimate whether elevations of complement C3a early in pregnancy are predictive of the subsequent development of adverse pregnancy outcomes.

METHODS

A plasma sample was obtained from each enrolled pregnant woman before 20 weeks of gestation. The cohort (n=1,002) was evaluated for the development of adverse pregnancy outcomes defined as hypertensive diseases of pregnancy (gestational hypertension or preeclampsia), preterm birth (before 37 weeks of gestation), premature rupture of the membranes, pregnancy loss (during the embryonic and fetal period), intrauterine growth restriction, and the composite outcome of any adverse outcome.

RESULTS

One or more adverse pregnancy outcomes occurred in 211 (21%) of the cohort. The mean levels (ng/mL) of C3a in early pregnancy were significantly (P=<.001) higher among women with one or more adverse outcomes (858±435) compared with women with an uncomplicated pregnancy (741±407). Adjusted for parity and prepregnancy body mass index, women with levels of C3a in the upper quartile in early pregnancy were three times more likely to have an adverse outcome later in pregnancy compared with women in the lowest quartile (95% confidence interval, 1.8-4.8; P<.001). The link between early elevated C3a levels and adverse pregnancy outcomes was driven primarily by individual significant (P<.05) associations of C3a with hypertensive diseases of pregnancy, preterm birth, and premature rupture of the membranes.

CONCLUSION

Elevated C3a as early as the first trimester of pregnancy is an independent predictive factor for adverse pregnancy outcomes, suggesting that complement-related inflammatory events in pregnancy contribute to the subsequent development of poor outcomes at later stages of pregnancy.

LEVEL OF EVIDENCE

II.

Severe neonatal complication of transverse lie after preterm premature rupture of membranes

Both transverse lie and preterm premature rupture of membranes (PPROM) are associated with neonatal morbidity and mortality. We present a neonate born at 29 weeks gestation with severe birth trauma after PPROM and transverse lie. The patient had extensive swelling and areas of desquamated and necrotic skin of the right lower limb. Neonatal compartment syndrome (NCS) was suspected. Perfusion of the limb improved after decompressing subcutaneous incisions. A fetus in transverse lie may be mechanically damaged in the case of PPROM, especially at an early gestational age. Early recognition is of great interest in the management and prognosis of NCS.

Rupture of membranes before the age of viability and birth after the age of viability: comparison of outcomes in a matched cohort study

OBJECTIVE

To compare composite adverse outcome rate of infants <32 weeks gestational age (GA) who were born after preterm premature rupture of membranes (PPROM) at previable gestation to those born without PPROM.

STUDY DESIGN

Retrospective review of prospective collected data for infants discharged between 2004 and 2007 was conducted. Cases were infants with >7 days of PPROM that occurred before 24 weeks. Matched cohort consisted of infants born without PPROM (matched for GA, sex and admission date). Composite adverse outcome was assessed considering death or any of the following three severe morbidities (severe neurological injury, severe retinopathy of prematurity or chronic lung disease).

RESULT

The 29 cases had higher mean severity of illness score compared with 74 matched infants. Mean duration of ROM was 45 vs 2 days and mean GA at the ROM was 21 vs 27 weeks, respectively. Logistic regression confirmed significantly higher risk of composite adverse outcome rates for cases (69 vs 47%; P=0.02, adjusted odds ratio 4.0, 95% CI 1.2, 13.6).

CONCLUSION

The survival rate for infants born at <32 weeks following PPROM at previable age has improved significantly; however, these infants had a higher rate of adverse composite neonatal outcome.

Diagnosis of premature rupture of membranes: inspiration from the past and insights for the future

OBJECTIVE

To review the diagnostic methods described to confirm premature rupture of membranes during pregnancy, and to assess their effectiveness in establishing the diagnosis.

DATA SOURCES AND EXTRACTION

The medical literature was searched to identify all relevant studies and reviews on methods for diagnosis of membrane rupture published in English up to January 31, 2009. Medline and the Cochrane databases were searched, and reference lists in identified articles were also examined. Articles not available through journals' online editions were retrieved by manual search.

STUDY SELECTION

We identified 71 original studies and reviews on diagnostic methods of chorioamniotic membrane rupture published in English. These articles were reviewed and results were summarized based on the diagnostic test assessed.

CONCLUSION

Recognition of the importance of and difficulties in confirmation of rupture of the chorioamniotic membranes pervades past and present obstetric publications. The subjectivity and poor sensitivity of early diagnostic techniques for confirmation of ruptured membranes sparked technical advancements using biochemical markers. None of these biochemical tests have gained popularity, although novel techniques involving placental markers such as placental alpha microglobulin-1 may provide a future solution to the problem of diagnosing chorioamniotic membrane rupture.

Selenium supplementation and premature (pre-labour) rupture of membranes: a randomised double-blind placebo-controlled trial

The aim was to determine if selenium supplementation during pregnancy reduces the occurrence of premature (pre-labour) rupture of membranes (PROM). A total of 166 primigravid pregnant women in the first trimester of pregnancy, were randomised to receive 100 microg of selenium (n = 83, drop-outs = 22) or a placebo (n = 83, drop-outs = 19) per day until delivery. The incidence of PROM, as well as serum selenium concentrations were evaluated at baseline and at the end of the study. Supplementation with selenium was associated with a significant increase in mean serum selenium concentration at term (p < 0.001). In contrast, mean serum selenium concentration remained unchanged in the control group (p > 0.05). The incidence of PROM was significantly lower in the selenium group (n = 8, 13.1%) than in the control group (n = 22, 34.4%) (p < 0.01). Our findings indicate that selenium supplementation (100 microg/day) in pregnant women effectively reduces the incidence of PROM.

Association between oxidative stress in pregnancy and preterm premature rupture of membranes

BACKGROUND

Premature rupture of membranes (PROM) is caused by collagen damage in the chorioamniotic sac leading to tearing. Reactive oxygen species (ROS) may be the cause of collagen damage. Isoprostanes (F(2)-IP) are produced by ROS attack on polyunsaturated fatty acids and are sensitive and specific biomarkers of lipid-peroxidation in vivo.

AIM

To verify whether oxidative stress occurs in pregnancies associated with preterm PROM.

METHODS

F(2)-IPs were measured in amniotic fluid of 16 pregnancies with preterm PROM (Group II) and 97 without PROM (Group I).

RESULTS

F(2)-IP concentrations (pg/mL) were significantly higher in group II than group I (p<0.0001). The ROC curve showed a sensitivity of 100% and a specificity of 84.5% at a cut-off of 124.4 pg/mL.

CONCLUSIONS

An association exists between oxidative stress in pregnancy and preterm PROM. The detection of amniotic fluid F(2)-IP concentrations seems to be a reliable predictive index of risk of preterm PROM.

Vaginal fluid urea and creatinine in diagnosis of premature rupture of membranes

OBJECTIVE

To evaluate the reliability of vaginal fluid urea and creatinine for the diagnosis of premature rupture of membranes (PROMs).

MATERIALS AND METHODS

A total of 139 pregnant women were recruited. Group I consisted of 47 patients with diagnosis of PROM confirmed by amniotic fluid pooling and nitrazine paper test. Group II consisted of 36 patients in whom diagnosis of PROM was suspected but unconfirmed by amniotic fluid pooling (+/-) and/or nitrazine paper test (+/-). Group III consisted of 56 pregnant women without any complaint or complication. All patients underwent speculum examination for amniotic fluid pooling, nitrazine paper test, vaginal washing fluid urea and creatinine sampling. One-way ANOVA test, Scheffe multiple comparison test and receiver operating characteristic curve analysis were used.

RESULTS

The mean vaginal fluid urea levels in group I, II, and III were 34.6 +/- 5.3, 2.4 +/- 5.3 and 1.3 +/- 6.2 mg/dl, respectively, where the difference was statistically significant (P < 0.001). The mean vaginal fluid creatinine concentrations of group I were, 1.5 +/- 0.3 mg/dl, found higher against the group II, 0.34 +/- 0.22 mg/dl, and group III, 0.28 +/- 0.23 mg/dl (P < 0.01). The sensitivity, specificity, positive predictivity, and negative predictivity were all 100% in detecting PROM by evaluation of vaginal fluid urea and creatinine concentration with a cut-off value of 12 and 0.6 mg/dl, respectively.

CONCLUSION

Vaginal washing fluid urea and creatinine determination for the diagnosis of PROM is a reliable, simple and rapid test.

Preterm and premature rupture of membranes in pregnancies after in vitro fertilization

Women conceiving by assisted reproduction are at higher risk for preterm and premature rupture of membranes. The aim of our study was to estimate and compare incidence of preterm premature rupture of membranes in singleton pregnancies of women who conceived by intrauterine insemination and in vitro fertilization, from 1999 to 2003. We investigated 87 women from the intrauterine insemination, and 102 from the in vitro fertilization program. There were no statistically significant differences in regard to preterm and premature rupture of membranes: p > 0.75 in two groups. The incidence of premature rupture of membranes was 2.30% (after intrauterine insemination) and 2.94% (after in vitro fertilization). There was no statistically significant differences in regard to preterm and premature rupture of membranes in women who conceived by insemination and in vitro fertilization. Estimated incidence of preterm and premature rupture of membranes was similar to the literature data and also similar to incidence after natural conception.