Observation of WWγ Production and Search for Hγ Production in Proton-Proton Collisions at sqrt[s]=13 TeV

The observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138  fb^{-1} is presented. The observed (expected) significance is 5.6 (5.1) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured fiducial cross section for WWγ is 5.9±0.8(stat)±0.8(syst)±0.7(modeling)  fb, in agreement with the next-to-leading order quantum chromodynamics prediction. The analysis is extended with a search for the associated production of the Higgs boson and a photon, which is generated by a coupling of the Higgs boson to light quarks. The result is used to constrain the Higgs boson couplings to light quarks.

New Structures in the J/ψJ/ψ Mass Spectrum in Proton-Proton Collisions at sqrt[s]=13 TeV

A search is reported for near-threshold structures in the J/ψJ/ψ invariant mass spectrum produced in proton-proton collisions at sqrt[s]=13  TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135  fb^{-1}. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638_{-38}^{+43}(stat)_{-31}^{+16}(syst)  MeV. Another structure with even higher significance is found at a mass of 6847_{-28}^{+44}(stat)_{-20}^{+48}(syst)  MeV, which is consistent with the X(6900) resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134_{-25}^{+48}(stat)_{-15}^{+41}(syst)  MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference.

Search for Scalar Leptoquarks Produced via τ-Lepton-Quark Scattering in pp Collisions at sqrt[s]=13 TeV

The first search for scalar leptoquarks produced in τ-lepton-quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138  fb^{-1}. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength.

Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138  fb^{-1} of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016-2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ(pp→A^{'}→χ_{1}χ_{2}) and the decay branching fraction B(χ_{2}→χ_{1}μ^{+}μ^{-}), where A^{'} is a dark photon and χ_{1} and χ_{2} are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter.

Luminosity determination using Z boson production at the CMS experiment

The measurement of Z boson production is presented as a method to determine the integrated luminosity of CMS data sets. The analysis uses proton-proton collision data, recorded by the CMS experiment at the CERN LHC in 2017 at a center-of-mass energy of 13Te V . Events with Z bosons decaying into a pair of muons are selected. The total number of Z bosons produced in a fiducial volume is determined, together with the identification efficiencies and correlations from the same data set, in small intervals of 20pb - 1 of integrated luminosity, thus facilitating the efficiency and rate measurement as a function of time and instantaneous luminosity. Using the ratio of the efficiency-corrected numbers of Z bosons, the precisely measured integrated luminosity of one data set is used to determine the luminosity of another. For the first time, a full quantitative uncertainty analysis of the use of Z  bosons for the integrated luminosity measurement is performed. The uncertainty in the extrapolation between two data sets, recorded in 2017 at low and high instantaneous luminosity, is less than 0.5%. We show that the Z boson rate measurement constitutes a precise method, complementary to traditional methods, with the potential to improve the measurement of the integrated luminosity.

Incidence and outcomes of uterine rupture in women with unscarred, preterm or prelabour uteri: data from the international network of obstetric survey systems

OBJECTIVE

Analysis of atypical cases of uterine rupture, namely, uterine rupture occurring in unscarred, preterm or prelabour uteri.

DESIGN

Descriptive multi-country population-based study.

SETTING

Ten high-income countries within the International Network of Obstetric Survey Systems.

POPULATION

Women with unscarred, preterm or prelabour ruptured uteri.

METHODS

We merged prospectively collected individual patient data in ten population-based studies of women with complete uterine rupture. In this analysis, we focused on women with uterine rupture of unscarred, preterm or prelabour ruptured uteri.

MAIN OUTCOME MEASURES

Incidence, women's characteristics, presentation and maternal and perinatal outcome.

RESULTS

We identified 357 atypical uterine ruptures in 3 064 923 women giving birth. Estimated incidence was 0.2 per 10 000 women (95% CI 0.2-0.3) in the unscarred uteri, 0.5 (95% CI 0.5-0.6) in the preterm uteri, 0.7 (95% CI 0.6-0.8) in the prelabour uteri, and 0.5 (95% CI 0.4-0.5) in the group with no previous caesarean. Atypical uterine rupture resulted in peripartum hysterectomy in 66 women (18.5%, 95% CI 14.3-23.5%), three maternal deaths (0.84%, 95% CI 0.17-2.5%) and perinatal death in 62 infants (19.7%, 95% CI 15.1-25.3%).

CONCLUSIONS

Uterine rupture in preterm, prelabour or unscarred uteri are extremely uncommon but were associated with severe maternal and perinatal outcome. We found a mix of risk factors in unscarred uteri, most preterm uterine ruptures occurred in caesarean-scarred uteri and most prelabour uterine ruptures in 'otherwise' scarred uteri. This study may increase awareness among clinicians and raise suspicion of the possibility of uterine rupture under these less expected conditions.

Inhibition of carbonic anhydrase using aspirin is a novel method to block schistosomiasis infection of the parasitic trematode, Schistosoma mansoni, in the intermediate snail host, Biomphalaria glabrata

Schistosomiasis is a major public health concern worldwide. Although praziquantel is currently available as the only treatment option for schistosomiasis, the absence of reliable diagnostic and prognostic tools highlights the need for the identification and characterization of new drug targets. Recently, we identified the B. glabrata homolog (accession number XP_013075832.1) of human CAXIV, showing 37% amino acid sequence identity, from a BLAST search in NCBI (National Center for Biotechnology Information). Carbonic Anhydrases (CAs) are metalloenzymes that catalyze the reversible hydration/dehydration of CO2/HCO3. These enzymes are associated with many physiological processes, and their role in tumorigenesis has been widely implicated. CAs create an acidic extracellular environment that facilitates the survival, metastasis, and growth of cancer cells. In this study, we investigated the role of CA inhibition in B. glabrata snails exposed to S. mansoni miracidia. We analyzed the expression of the B. glabrata CA encoding transcript in juvenile susceptible and resistant snails, with and without exposure to S. mansoni. Our results showed that the expression of the CA mRNA encoding transcript was upregulated during early and prolonged infection in susceptible snails (BBO2), but not in the resistant BS-90 stock. Notably, sodium salicylate, a form of aspirin, inhibited the expression of CA, post-exposure, to the parasite. Increasing research between parasites and cancer has shown that schistosomes and cancer cells share similarities in their capacity to proliferate, survive, and evade host immune mechanisms. Here, we show that this model system is a potential new avenue for understanding the role of CA in the metastasis and proliferation of cancer cells. Further studies are needed to explore the potential of CA as a biomarker for infection in other schistosomiasis-causing parasites, including S. japonicum and S. haematobium.

Observation of the Rare Decay of the η Meson to Four Muons

A search for the rare η→μ^{+}μ^{-}μ^{+}μ^{-} double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb^{-1}. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ^{+}μ^{-} decay as normalization, the branching fraction B(η→μ^{+}μ^{-}μ^{+}μ^{-})=[5.0±0.8(stat)±0.7(syst)±0.7(B_{2μ})]×10^{-9} is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions.

Mycobacterial formation of intracellular lipid inclusions is a dynamic process associated with rapid replication

Intracellular lipid inclusions (ILI) are triacylglyceride rich organelles produced by mycobacteria thought to serve as energy reservoirs. It is believed that ILI are formed as a result of a dosR mediated transition from replicative growth to non-replicating persistence (NRP). ILI rich Mycobacterium tuberculosis (Mtb) bacilli have been reported during infection and in sputum, establishing their importance in Mtb pathogenesis. Studies conducted in mycobacteria such as Mycobacterium smegmatis, Mycobacterium abscessus, or lab Mtb strains have demonstrated ILI formation in the presence of hypoxic, nitric oxide, nutrient limitation, or low nitrogen stress, conditions believed to emulate the host environment within which Mtb resides. Here, we show that M. marinum and clinical Mtb isolates make ILI during active replication in axenic culture independent of environmental stressors. By tracking ILI formation dynamics we demonstrate that ILI are quickly formed in the presence of fresh media or exogenous fatty acids but are rapidly depleted while bacteria are still actively replicating. We also show that the cell envelope is an alternate site for neutral lipid accumulation observed during stationary phase. In addition, we screen a panel of 60 clinical isolates and observe variation in ILI production during early log phase growth between and among Mtb lineages. Finally, we show that dosR expression level does not strictly correlate with ILI accumulation in fresh clinical isolates. Taken together, our data provide evidence of an active ILI formation pathway in replicating mycobacteria cultured in the absence of stressors, suggesting a decoupling of ILI formation from NRP.

A national cohort study to investigate the association between ethnicity and the provision of care in obstetric anaesthesia in England between 2011 and 2021

There is evidence that ethnic inequalities exist in maternity care in the UK, but those specifically in relation to UK obstetric anaesthetic care have not been investigated before. Using routine national maternity data for England (Hospital Episode Statistics Admitted Patient Care) collected between March 2011 and February 2021, we investigated ethnic differences in obstetric anaesthetic care. Anaesthetic care was identified using OPCS classification of interventions and procedures codes. Ethnic groups were coded according to the hospital episode statistics classifications. Multivariable negative binominal regression was used to model the relationship between ethnicity and obstetric anaesthesia (general and neuraxial anaesthesia) by calculating adjusted incidence ratios for the following: differences in maternal age; geographical residence; deprivation; admission year; number of previous deliveries; and comorbidities. Women giving birth vaginally and by caesarean section were considered separately. For women undergoing elective caesarean births, after adjustment for available confounders, general anaesthesia was 58% more common in Caribbean (black or black British) women (adjusted incidence ratio [95%CI] 1.58 [1.26-1.97]) and 35% more common in African (black or black British) women (1.35 [1.19-1.52]). For women who had emergency caesarean births, general anaesthesia was 10% more common in Caribbean (black or black British) women (1.10 [1.00-1.21]) than British (white) women. For women giving birth vaginally (excluding assisted vaginal births), Bangladeshi (Asian or Asian British), Pakistani (Asian or Asian British) and Caribbean (black or black British) women were, respectively, 24% (0.76 [0.74-0.78]), 15% (0.85 [0.84-0.87]) and 8% (0.92 [0.89-0.94]) less likely than British (white) women to receive neuraxial anaesthesia. This observational study cannot determine the causes for these disparities, which may include unaccounted confounders. Our findings merit further research to investigate potentially remediable factors such as inequality of access to appropriate obstetric anaesthetic care.

Defining vulnerability subgroups among pregnant women using pre-pregnancy information: a latent class analysis

BACKGROUND

Early detection of vulnerability during or before pregnancy can contribute to optimizing the first 1000 days, a crucial period for children's development and health. We aimed to identify classes of vulnerability among pregnant women in the Netherlands using pre-pregnancy data on a wide range of social risk and protective factors, and validate these classes against the risk of adverse outcomes.

METHODS

We conducted a latent class analysis based on 42 variables derived from nationwide observational data sources and self-reported data. Variables included individual, socioeconomic, lifestyle, psychosocial and household characteristics, self-reported health, healthcare utilization, life-events and living conditions. We compared classes in relation to adverse outcomes using logistic regression analyses.

RESULTS

In the study population of 4172 women, we identified five latent classes. The largest 'healthy and socioeconomically stable'-class [n = 2040 (48.9%)] mostly shared protective factors, such as paid work and positively perceived health. The classes 'high care utilization' [n = 485 (11.6%)], 'socioeconomic vulnerability' [n = 395 (9.5%)] and 'psychosocial vulnerability' [n = 1005 (24.0%)] were characterized by risk factors limited to one specific domain and protective factors in others. Women classified into the 'multidimensional vulnerability'-class [n = 250 (6.0%)] shared multiple risk factors in different domains (psychosocial, medical and socioeconomic risk factors). Multidimensional vulnerability was associated with adverse outcomes, such as premature birth and caesarean section.

CONCLUSIONS

Co-existence of multiple risk factors in various domains is associated with adverse outcomes for mother and child. Early detection of vulnerability and strategies to improve parental health and well-being might benefit from focussing on different domains and combining medical and social care and support.

1337 IMPROVING THE PERI-OPERATIVE MANAGEMENT OF ANTICOAGULATION IN PATIENTS WITH NECK OF FEMUR FRACTURES (NOFFS)

Introduction

Neck of femur fractures (NOFFs) are a clinically significant diagnosis, with 10% of patients dying within one month of diagnosis [1]. There is a strong association between earlier surgery and improvement in postoperative outcomes [2]. Taking anticoagulation can cause delays in patients being operated on. At Homerton University Hospital (HUH), no previous guideline existed to aid specifically in the management of patients with NOFFs on anticoagulation. We created a guideline in order to reduce delays to theatre, in keeping with national guidance (<36 hours to operation).

Methods

We audited all patients in 2020 admitted to HUH with NOFFs taking anticoagulation. A guideline was then created, reflecting new national guidance [3] on the management of anticoagulation pre-operatively for NOFF patients. Three PDSA cycles were completed, with repeat audit cycles following dissemination and teaching of guideline to relevant clinical groups.

Results

Following implementation of our guideline, 56% of patients had surgery within 36 hours of admission, compared to 25% previously. Advice being given to the admitting team regarding timing of the operation was more consistent, and the admitting team needed to ask for advice less often. There was an overall increase in consistency of management.

Conclusions

Ensuring NOFFs are operated on promptly reduces the risk of co-morbidity and mortality [2]. There are often incorrect delays to theatre following anticoagulation administration due to perceived risk of bleeding. We created and implemented a new guideline, which successfully reduced time taken for patients on anticoagulation to be taken to theatre for operation.

References

[1] NICE. ‘Hip Fracture: Management’. Clinical guideline. Published: 22 June 2011. Accessed at: nice.org.uk/guidance/cg124.

[2] Seong YJ, Shin WC, Moon NH, Suh KT. Timing of Hip-fracture Surgery in Elderly Patients. Hip Pelvis. 2020;32(1):11-16. doi: 10.5371/hp.2020.32.1.11.

[3] Griffiths R, Babu S, Dixon P et al. Ray), Guideline for the management of hip fractures. Anaesthesia 2020; 76: 225–37.

Co-production in public health research grant writing: engaging underserved migrant mothers in the UK

Background

In the UK, one in three births is to a non-UK born woman, but there is a gap in co-produced research to explore their experiences. The National Institute for Health and Care Research (NIHR) defines co-production as ‘an approach in which researchers, practitioners, and members of the public work together, sharing power and responsibility'. This project co-produced a grant proposal to improve maternity care for underserved migrant women in the UK. We reflect on transferrable learning for engaging those whose voices are less often heard in grant writing.

Methods

An expert by experience, an underserved migrant woman who gave birth in the UK, joined the research team. Four online engagement workshops were conducted; two involved only migrant women, two were multi-disciplinary. 26 underserved migrant women attended. NIHR INVOLVE public involvement guidance was consulted.

Results

Women said they were often asked about negative experiences which felt disempowering, and rarely asked about solutions. Thus, we shifted the focus of our work to co-designing solutions. Women said that having an expert by experience co-host workshops encouraged engagement, so we integrated this into our methods. Some women were uncomfortable in professional groups. Thus, our proposed steering and focus groups will have an expert by experience subgroup with elected members attending multi-disciplinary groups. We will engage mostly online as women preferred this to enable flexibility with childcare. The lead expert by experience helped form the proposal through brainstorming, co-drafting, and feedback; experts by experience commented on the draft via email and workshops. The lead expert by experience wished to gain further experience of research methods, for which we requested additional funding.

Conclusions

This project highlights the immense potential for co-production in public health research, and the value of adapting research planning to maximise the voices of the less often heard.

Key messages

• Engaging experts by experiences in public health research planning is key to ensuring our work addresses the needs of underserved communities.

• Co-Production of research requires determination to involve those whose voices are less often heard from the beginning of the research process, and to commit to joined working throughout.

A Thermodynamic Model for Interpreting Tryptophan Excitation-Energy-Dependent Fluorescence Spectra Provides Insight Into Protein Conformational Sampling and Stability

It is now over 30 years since Demchenko and Ladokhin first posited the potential of the tryptophan red edge excitation shift (REES) effect to capture information on protein molecular dynamics. While there have been many key efforts in the intervening years, a biophysical thermodynamic model to quantify the relationship between the REES effect and protein flexibility has been lacking. Without such a model the full potential of the REES effect cannot be realized. Here, we present a thermodynamic model of the tryptophan REES effect that captures information on protein conformational flexibility, even with proteins containing multiple tryptophan residues. Our study incorporates exemplars at every scale, from tryptophan in solution, single tryptophan peptides, to multitryptophan proteins, with examples including a structurally disordered peptide, de novo designed enzyme, human regulatory protein, therapeutic monoclonal antibodies in active commercial development, and a mesophilic and hyperthermophilic enzyme. Combined, our model and data suggest a route forward for the experimental measurement of the protein REES effect and point to the potential for integrating biomolecular simulation with experimental data to yield novel insights.

PIWI silencing mechanism involving the retrotransposon nimbus orchestrates resistance to infection with Schistosoma mansoni in the snail vector, Biomphalaria glabrata

Background

Schistosomiasis remains widespread in many regions despite efforts at its elimination. By examining changes in the transcriptome at the host-pathogen interface in the snail Biomphalaria glabrata and the blood fluke Schistosoma mansoni, we previously demonstrated that an early stress response in juvenile snails, manifested by induction of heat shock protein 70 (Hsp 70) and Hsp 90 and of the reverse transcriptase (RT) domain of the B. glabrata non-LTR- retrotransposon, nimbus, were critical for B. glabrata susceptibility to S. mansoni. Subsequently, juvenile B. glabrata BS-90 snails, resistant to S. mansoni at 25°C become susceptible by the F2 generation when maintained at 32°C, indicating an epigenetic response.

Methodology/Principal findings

To better understand this plasticity in susceptibility of the BS-90 snail, mRNA sequences were examined from S. mansoni exposed juvenile BS-90 snails cultured either at 25°C (non-permissive temperature) or 32°C (permissive). Comparative analysis of transcriptomes from snails cultured at the non-permissive and permissive temperatures revealed that whereas stress related transcripts dominated the transcriptome of susceptible BS-90 juvenile snails at 32°C, transcripts encoding proteins with a role in epigenetics, such as PIWI (BgPiwi), chromobox protein homolog 1 (BgCBx1), histone acetyltransferase (BgHAT), histone deacetylase (BgHDAC) and metallotransferase (BgMT) were highly expressed in those cultured at 25°C. To identify robust candidate transcripts that will underscore the anti-schistosome phenotype in B. glabrata, further validation of the differential expression of the above transcripts was performed by using the resistant BS-90 (25°C) and the BBO2 susceptible snail stock whose genome has now been sequenced and represents an invaluable resource for molecular studies in B. glabrata. A role for BgPiwi in B. glabrata susceptibility to S. mansoni, was further examined by using siRNA corresponding to the BgPiwi encoding transcript to suppress expression of BgPiwi, rendering the resistant BS-90 juvenile snail susceptible to infection at 25°C. Given transposon silencing activity of PIWI as a facet of its role as guardian of the integrity of the genome, we examined the expression of the nimbus RT encoding transcript at 120 min after infection of resistant BS90 piwi-siRNA treated snails. We observed that nimbus RT was upregulated, indicating that modulation of the transcription of the nimbus RT was associated with susceptibility to S. mansoni in BgPiwi-siRNA treated BS-90 snails. Furthermore, treatment of susceptible BBO2 snails with the RT inhibitor lamivudine, before exposure to S. mansoni, blocked S. mansoni infection concurrent with downregulation of the nimbus RT transcript and upregulation of the BgPiwi encoding transcript in the lamivudine-treated, schistosome-exposed susceptible snails.

Conclusions and significance

These findings support a role for the interplay of BgPiwi and nimbus in the epigenetic modulation of plasticity of resistance/susceptibility in the snail-schistosome relationship.

Progress is being made to eliminate schistosomiasis, a tropical disease that remains endemic in the tropics and neotropics. In 2020, WHO proposed controlling the snail population as part of a strategy toward reducing schistosomiasis, a vector borne disease, by 2025. The life cycle of the causative parasite is, however, complex and in the absence of vaccines, new drugs, and access to clean water and sanitation, reduction of schistosomiasis will remain elusive. To break the parasite’s life cycle during the snail stage of its development, a better understanding of the molecular basis of how schistosomes survive, or not, in the snail is required. By examining changes in the transcriptome at the host-pathogen interface in the snail Biomphalaria glabrata and Schistosoma mansoni, we showed that early stress response, manifested by the induction of Heat Shock Proteins (Hsps) and the RT domain of the non-LTR retrotransposon, nimbus, were critical for snail susceptibility. Subsequently, juvenile B. glabrata BS-90 snails, resistant to S. mansoni at 25°C were observed to become susceptible by the F2 generation when maintained at 32°C, indicating an epigenetic response. This study confirms these earlier results and shows an interplay between PIWI and nimbus in the anti-schistosome response in the snail host.

Anaphylaxis in pregnancy: a population-based multinational European study

Anaphylaxis in pregnancy is a rare but severe complication for both mother and infant. Population-based data on anaphylaxis in pregnancy are lacking from mainland European countries. This multinational study presents the incidence, causative agents, management and maternal and infant outcomes of anaphylaxis in pregnancy. This descriptive multinational study used a combination of retrospective (Finnish medical registries) and prospective population-based studies (UK, France, Belgium and the Netherlands) to identify cases of anaphylaxis. Sixty-five cases were identified among 4,446,120 maternities (1.5 per 100,000 maternities; 95%CI 1.1-1.9). The incidence did not vary between countries. Approximately three-quarters of reactions occurred at the time of delivery. The most common causes were antibiotics in 27 women (43%), and anaesthetic agents in 11 women (17%; including neuromuscular blocking drugs, 7), which varied between countries. Anaphylaxis had very poor outcomes for one in seven mothers and one in seven babies; the maternal case fatality rate was 3.2% (95%CI 0.4-11.0) and the neonatal encephalopathy rate was 14.3% (95%CI 4.8-30.3). Across Europe, anaphylaxis related to pregnancy is rare despite having a multitude of causative agents and different antibiotic prophylaxis protocols.

AutoMicrobic System for Biochemical Identification of Listeria Species Isolated From Foods: Collaborative Study

A collaborative study was conducted to evaluate the performance of the AutoMicrobic System Gram- Positive Identification (GPI) and Gram-Negative Identification (GNI) test kits to biochemically characterize Listeria spp. Thirteen laboratories each tested 97 food and environmental isolates, representing the 7 species of Listeria, as well as 11 additional genera of Gram-positive rods. Each collaborator inoculated both a GPI and a GNI card with a pure culture of each organism. The AutoMicrobic System identified the isolates and printed out the biochemical results. The GPI card is used to obtain a species identification and a mannitol reaction result, and the GNI card is used to obtain rhamnose and xylose reaction results. Organisms are classified into species groups and can be further distinguished on the basis of hemolysis or nitrate reduction tests. The AutoMicrobic System method correctly classified 90.8% of the Listeria spp. isolates and 100% of the non-Listeria isolates. The AutoMicrobic System method was adopted first action by AOAC International for the biochemical characterization of Listeria spp. isolated from food and environmental sources.

The identification of key indicators to drive quality improvement in obstetric anaesthesia: results of the Obstetric Anaesthetists' Association/National Perinatal Epidemiology Unit collaborative Delphi project

A three‐stage Delphi survey process was undertaken to identify the quality indicators considered the most relevant to obstetric anaesthesia. The initial quality indicators assessed were derived from national peer‐reviewed publications and were divided into service provision, service quality and clinical outcomes. A range of stakeholders were invited to participate and divided into three panels: obstetric anaesthetists; other maternity care health professionals; and women who had used maternity services. In total, 133 stakeholders registered to participate with 80% completing all three phases of the survey process. Participants ranked indicators for their relative importance using the grading of recommendations assessment, development and evaluation scale. From an initial list of 31 quality indicators, 11 indicators were rated as extremely important by > 90% of participants in at least two panels. These 11 indicators were presented to stakeholders; they were asked to vote for the five indicators they considered most relevant and useful for assessing and benchmarking the quality of obstetric anaesthesia provided. The indicators chosen were: the percentage of women who had an epidural/combined spinal‐epidural for labour analgesia with accidental dural puncture; the presence of guidelines for the referral of patients to an anaesthetist for antenatal review; whether there are dedicated elective caesarean section lists; the availability of point‐of‐care testing for estimation of haemoglobin concentration; and the percentage of epidurals for labour analgesia that provided adequate pain relief within 45 min of the start of epidural insertion. These indicators may be used for quality improvement and national benchmarking to support the implementation of quality standards in obstetric anaesthesia.

Surveillance of congenital Zika syndrome in England and Wales: methods and results of laboratory, obstetric and paediatric surveillance

The spread of the Zika virus (ZIKV) in the Americas led to large outbreaks across the region and most of the Southern hemisphere. Of greatest concern were complications following acute infection during pregnancy. At the beginning of the outbreak, the risk to unborn babies and their clinical presentation was unclear. This report describes the methods and results of the UK surveillance response to assess the risk of ZIKV to children born to returning travellers. Established surveillance systems operating within the UK - the paediatric and obstetric surveillance units for rare diseases, and national laboratory monitoring - enabled rapid assessment of this emerging public health threat. A combined total of 11 women experiencing adverse pregnancy outcomes after possible ZIKV exposure were reported by the three surveillance systems; five miscarriages, two intrauterine deaths and four children with clinical presentations potentially associated with ZIKV infection. Sixteen women were diagnosed with ZIKV during pregnancy in the UK. Amongst the offspring of these women, there was unequivocal laboratory evidence of infection in only one child. In the UK, the number and risk of congenital ZIKV infection for travellers returning from ZIKV-affected countries is very small.

Identifying avoidable switchboard delays in England's NHS hospitals: phase one of the national SWITCH project

BACKGROUND

Inter-hospital communication frequently requires mediation via a switchboard. Identifying and eliminating switchboard inefficiencies may improve patient care.

METHODS

All 175 acute hospital switchboards in England were contacted six times. Call contents and duration were recorded. No clinician calls or bleeps were connected.

RESULTS

The mean delay before contacting a switchboard operative was 55±46 seconds. 115 hospitals (66%) used automated switchboards; 34 of these (30%) had infection control messages. Robot operators introduced an additional 40 second delay versus humans (mean 70.3±28 versus 29.8±23 seconds, p<0.0001). Multivariate analysis identified robot operators (HR 5.1, p<0.0001) and infection control messages (HR 2.9, p=0.003) as predictors of delays over 60 seconds.

CONCLUSIONS

There are significant avoidable delays in contacting switchboard operatives across England. Quality improvement is underway.

The incidence, characteristics, management and outcomes of anaphylaxis in pregnancy: a population-based descriptive study

OBJECTIVE

The aim of this study was to estimate the incidence of anaphylaxis in pregnancy and describe the management and outcomes in the UK.

DESIGN

A population-based descriptive study using the UK Obstetric Surveillance System (UKOSS).

SETTING

All consultant-led maternity units in the UK.

POPULATION

All pregnant women who had anaphylaxis between 1 October 2012 and 30 September 2015. Anaphylaxis was defined as a severe, life-threatening generalised or systemic hypersensitivity reaction.

METHODS

Prospective case notification using UKOSS.

MAIN OUTCOME MEASURES

Maternal mortality, severe maternal morbidity, neonatal mortality and severe neonatal morbidity.

RESULTS

There were 37 confirmed cases of anaphylaxis in pregnancy, giving an estimated incidence of 1.6 (95% CI: 1.1-2.2) per 100 000 maternities. Four cases of anaphylaxis were in women with known penicillin allergies: two received co-amoxiclav and two cephalosporins. Twelve women had anaphylaxis following prophylactic use of antibiotics at the time of a caesarean delivery. Prophylactic use of antibiotics for Group B streptococcal infection accounted for anaphylaxis in one woman. Two women died (5%), 14 (38%) women were admitted to intensive care and seven women (19%) had one or more additional severe maternal morbidities, which included three haemorrhagic events, two cardiac arrests, one thrombotic event and one pneumonia. No infants died; however, in those infants whose mother had anaphylaxis before delivery (n = 18) there were seven (41%) neonatal intensive care unit admissions, three preterm births and one baby was cooled for neonatal encephalopathy.

CONCLUSIONS

Anaphylaxis is a rare severe complication of pregnancy and frequently the result of a reaction to antibiotic administration. This study highlights the seriousness of the outcomes of this condition for the mother. The low incidence is reassuring given the large proportion of the pregnant population that receive prophylactic antibiotics during delivery.

TWEETABLE ABSTRACT

Anaphylaxis is a rare severe complication of pregnancy and frequently the result of a reaction to antibiotic administration.

Developing a set of consensus indicators to support maternity service quality improvement: using Core Outcome Set methodology including a Delphi process

OBJECTIVE

To develop a core metric set to monitor the quality of maternity care.

DESIGN

Delphi process followed by a face-to-face consensus meeting.

SETTING

English maternity units.

POPULATION

Three representative expert panels: service designers, providers and users.

MAIN OUTCOME MEASURES

Maternity care metrics judged important by participants.

METHODS

Participants were asked to complete a two-phase Delphi process, scoring metrics from existing local maternity dashboards. A consensus meeting discussed the results and re-scored the metrics.

RESULTS

In all, 125 distinct metrics across six domains were identified from existing dashboards. Following the consensus meeting, 14 metrics met the inclusion criteria for the final core set: smoking rate at booking; rate of birth without intervention; caesarean section delivery rate in Robson group 1 women; caesarean section delivery rate in Robson group 2 women; caesarean section delivery rate in Robson group 5 women; third- and fourth-degree tear rate among women delivering vaginally; rate of postpartum haemorrhage of ≥1500 ml; rate of successful vaginal birth after a single previous caesarean section; smoking rate at delivery; proportion of babies born at term with an Apgar score <7 at 5 minutes; proportion of babies born at term admitted to the neonatal intensive care unit; proportion of babies readmitted to hospital at <30 days of age; breastfeeding initiation rate; and breastfeeding rate at 6-8 weeks.

CONCLUSIONS

Core outcome set methodology can be used to incorporate the views of key stakeholders in developing a core metric set to monitor the quality of care in maternity units, thus enabling improvement.

TWEETABLE ABSTRACT

Achieving consensus on core metrics for monitoring the quality of maternity care.

The DiPEP study: an observational study of the diagnostic accuracy of clinical assessment, D-dimer and chest x-ray for suspected pulmonary embolism in pregnancy and postpartum

Objective

To identify clinical features associated with pulmonary embolism (PE) diagnosis and determine the accuracy of decision rules and D‐dimer for diagnosing suspected PE in pregnant/postpartum women

Design

Observational cohort study augmented with additional cases.

Setting

Emergency departments and maternity units at eleven prospectively recruiting sites and maternity units in the United Kingdom Obstetric Surveillance System (UKOSS)

Population

324 pregnant/postpartum women with suspected PE and 198 pregnant/postpartum women with diagnosed PE

Methods

We recorded clinical features, elements of clinical decision rules, D‐dimer measurements, imaging results, treatments and adverse outcomes up to 30 days

Main outcome measures

Women were classified as having PE on the basis of imaging, treatment and adverse outcomes by assessors blind to clinical features and D‐dimer. Primary analysis was limited to women with conclusive imaging to avoid work‐up bias. Secondary analyses included women with clinically diagnosed or ruled out PE.

Results

The only clinical features associated with PE on multivariate analysis were age (odds ratio 1.06; 95% confidence interval 1.01–1.11), previous thrombosis (3.07; 1.05–8.99), family history of thrombosis (0.35; 0.14–0.90), temperature (2.22; 1.26–3.91), systolic blood pressure (0.96; 0.93–0.99), oxygen saturation (0.87; 0.78–0.97) and PE‐related chest x‐ray abnormality (13.4; 1.39–130.2). Clinical decision rules had areas under the receiver‐operator characteristic curve ranging from 0.577 to 0.732 and no clinically useful threshold for decision‐making. Sensitivities and specificities of D‐dimer were 88.4% and 8.8% using a standard threshold and 69.8% and 32.8% using a pregnancy‐specific threshold.

Conclusions

Clinical decision rules and D‐dimer should not be used to select pregnant or postpartum women with suspected PE for further investigation. Clinical features and chest x‐ray appearances may have counter‐intuitive associations with PE in this context.

Tweetable abstract

Clinical decision rules and D‐dimer are not helpful for diagnosing pregnant/postpartum women with suspected PE

Clinical decision rules and D‐dimer are not helpful for diagnosing pregnant/postpartum women with suspected PE.

The International Network of Obstetric Survey Systems study of uterine rupture: a descriptive multi-country population-based study

OBJECTIVE

International comparison of complete uterine rupture.

DESIGN

Descriptive multi-country population-based study.

SETTING

International.

POPULATION

International Network of Obstetric Survey Systems (INOSS).

METHODS

We merged individual data, collected prospectively in nine population-based studies, of women with complete uterine rupture, defined as complete disruption of the uterine muscle and the uterine serosa, regardless of symptoms and rupture of fetal membranes.

MAIN OUTCOME MEASURES

Prevalence of complete uterine rupture, regional variation and correlation with rates of caesarean section (CS) and trial of labour after CS (TOLAC). Severe maternal and perinatal morbidity and mortality.

RESULTS

We identified 864 complete uterine ruptures in 2 625 017 deliveries. Overall prevalence was 3.3 (95% CI 3.1-3.5) per 10 000 deliveries, 22 (95% CI 21-24) in women with and 0.6 (95% CI 0.5-0.7) in women without previous CS. Prevalence in women with previous CS was negatively correlated with previous CS rate (ρ = -0.917) and positively correlated with TOLAC rate of the background population (ρ = 0.600). Uterine rupture resulted in peripartum hysterectomy in 87 of 864 women (10%, 95% CI 8-12%) and in a perinatal death in 116 of 874 infants (13.3%, 95% CI 11.2-15.7) whose mother had uterine rupture. Overall rate of neonatal asphyxia was 28% in neonates who survived.

CONCLUSIONS

Higher prevalence of complete uterine ruptures per TOLAC was observed in countries with low previous CS and high TOLAC rates. Rates of hysterectomy and perinatal death are about 10% following complete uterine rupture, but in women undergoing TOLAC the rates are extremely low (only 2.2 and 3.2 per 10 000 TOLACs, respectively.) TWEETABLE ABSTRACT: Prevalence of complete uterine rupture is higher in countries with low previous CS and high TOLAC rates.

Caesarean scar pregnancy in the UK: a national cohort study

OBJECTIVE

To estimate the incidence of caesarean scar pregnancy (CSP) and to describe the management outcomes associated with this condition.

DESIGN

A national cohort study using the UK Early Pregnancy Surveillance Service (UKEPSS).

SETTING

86 participating Early Pregnancy Units.

POPULATION

All women diagnosed in the participating units with CSP between November 2013 and January 2015.

METHODS

Cohort study of women identified through the UKEPSS monthly mailing system.

MAIN OUTCOME MEASURES

Incidence, clinical outcomes and complications.

RESULTS

102 cases of CSP were reported, with an estimated incidence of 1.5 per 10 000 (95% CI 1.1-1.9) maternities. Full outcome data were available for 92 women. Management was expectant in 21/92 (23%), medical in 15/92 (16%) and surgical in 56/92 (61%). The success rates of expectant, medical and surgical management were 43% (9/21), 46% (7/15) and 96% (54/56), respectively. The complication rates were 15/21 (71%) with expectant, 9/15 (60%) with medical and 20/56 (36%) with surgical management. Discharge from care (median number of days) was 82 (range 37-174) with expectant, 21 (range 10-31) with medical and 11 (range 4-49) with surgical management.

CONCLUSIONS

Surgical management appears to be associated with a high success rate, low complication rate and short post-treatment follow up.

TWEETABLE ABSTRACT

Surgery for CSP appears to be successful, with low complication rates and short post-treatment follow up.

Sheep residual feed intake and feeding behaviour: are ‘nibblers’ or ‘binge eaters’ more efficient?

Efficient liveweight gain is an important component of profitable livestock systems. In cattle, studies of residual feed intake (RFI) suggest that there are behavioural differences between efficient and inefficient animals; more efficient animals have less frequent, larger feed events. There is limited understanding of the association between feeding behaviour and feed conversion efficiency (measured as RFI) in sheep. We hypothesised that more efficient sheep would have lower daily number of meals but larger meal size than would less efficient sheep and that feeding behaviour would be repeatable between measurements conducted using the same sheep at different ages. Feeding behaviour was monitored at post-weaning (average 311 days) and hogget (average 533 days) age in a single cohort of maternal composite 2014-born ewes undergoing feed-efficiency testing. Feed intake (kg/day) and daily feeding behaviour (meal number, meal size and eating rate) were recorded by using automated feeders. Feed intake was recorded daily for a minimum of 40 days (mean 41 days), following a 14-day adaptation period. Animals were fed a pelleted hay-based diet, with liveweight measured three times per week. At both ages of measurement, a positive (P < 0.01) linear relationship was established between average daily number of meals and RFI. In these cohorts, as daily number of meals increased, RFI became more positive (less efficient). Meal size (kg DM) was also related to RFI (P < 0.05) when measured at the hogget age, with meal size decreasing with an increasing RFI (less efficient animals had smaller meals). These analyses suggest that sheep feeding behaviour, and in particular daily meal number, is associated with feed efficiency.

Defining definitions: a Delphi study to develop a core outcome set for conditions of severe maternal morbidity

OBJECTIVE

Develop a core outcome set of international consensus definitions for severe maternal morbidities.

DESIGN

Electronic Delphi study.

SETTING

International.

POPULATION

Eight expert panels.

METHODS

All 13 high-income countries represented in the International Network of Obstetric Surveillance Systems (INOSS) nominated five experts per condition of morbidity, who submitted possible definitions. From these suggestions, a steering committee distilled critical components: eclampsia: 23, amniotic fluid embolism: 15, pregnancy-related hysterectomy: 11, severe primary postpartum haemorrhage: 19, uterine rupture: 20, abnormally invasive placentation: 12, spontaneous haemoperitoneum in pregnancy: 16, and cardiac arrest in pregnancy: 10. These components were assessed by the expert panel using a 5-point Likert scale, following which a framework for an encompassing definition was constructed. Possible definitions were evaluated in rounds until a rate of agreement of more than 70% was reached. Expert commentaries were used in each round to improve definitions.

MAIN OUTCOME MEASURES

Definitions with a rate of agreement of more than 70%.

RESULTS

The invitation to participate in one or more of eight Delphi processes was accepted by 103 experts from 13 high-income countries. Consensus definitions were developed for all of the conditions.

CONCLUSION

Consensus definitions for eight morbidity conditions were successfully developed using the Delphi process. These should be used in national registrations and international studies, and should be taken up by the Core Outcomes in Women's and Newborn Health initiative.

TWEETABLE ABSTRACT

Consensus definitions for eight morbidity conditions were successfully developed using the Delphi process.

Severe primary autoimmune thrombocytopenia in pregnancy: a national cohort study

OBJECTIVE

To quantify the incidence of severe autoimmune thrombocytopenia (ITP) in pregnancy in the UK, determine current treatment strategies, and establish maternal and neonatal morbidity and mortality associated with severe ITP in pregnancy.

DESIGN

A prospective national cohort study.

SETTING

UK.

POPULATION

Women with severe ITP, defined as platelets <50 × 10⁹ /L in pregnancy or antenatal treatment of isolated low platelets.

METHODS

Data collected via the UK Obstetric Surveillance System (UKOSS) between 1 June 2013 and 31 January 2015 from all UK consultant-led obstetric units.

MAIN OUTCOME MEASURE

Incidence of severe ITP in pregnancy.

RESULTS

The estimated incidence of severe ITP in pregnancy is 0.83 per 10 000 maternities (95% CI 0.68-1.00). A total of 22 pregnant women (21%) did not receive any antenatal therapy, and 85 pregnant women (79%) received therapy. There was no difference between asymptomatic treated and untreated cohorts in severity of disease or outcome. Postpartum haemorrhage (51%) and severe postpartum haemorrhage (21%) was reported more frequently than the rate reported in the general pregnant population (5-10%). No neonates required treatment for thrombocytopenia and there were no cases of neonatal intracranial bleeding.

CONCLUSIONS

Current UK management of severe ITP in pregnancy results in an exceptionally low morbidity and mortality for the neonate. Mothers with ITP remain at increased risk of severe postpartum haemorrhage, and should be delivered at units that have the capacity to manage severe PPH effectively. Whilst balancing the risks for pregnancy from prophylactic antenatal treatment in asymptomatic women against observed low disease morbidity, we may be over treating asymptomatic patients.

TWEETABLE ABSTRACT

UKOSS study of severe ITP in pregnancy shows exceptionally low neonatal morbidity with current UK management.

Hirschsprung's disease in the UK and Ireland: incidence and anomalies

OBJECTIVES

To describe clinical characteristics and preoperative management of a national cohort of infants with Hirschsprung's disease (HD).

DESIGN

Population-based cohort study of all live-born infants with HD born in the UK and Ireland from October 2010 to September 2012.

SETTING

All 28 paediatric surgical centres in the UK and Ireland.

PARTICIPANTS

305 infants presenting before 6 months of age with histologically proven HD.

MAIN OUTCOME MEASURES

Incidence, clinical characteristics including gestational age, birth weight, gender, associated anomalies; age and clinical features at presentation; and use of rectal washouts or stoma.

RESULTS

The incidence of HD in the UK and Ireland was 1.8 per 10 000 live births (95% CI 1.5 to 1.9). Male to female ratio was 3.3:1. An associated anomaly was identified in 23% (69), with 15% (47) having a recognisable syndrome. The proportion of infants who presented and were diagnosed in the neonatal period was 91.5% (279) and 83.9% (256), respectively. 23.9% (73) and 44.2% (135) passed meconium within 24 and 48 hours of birth. 81% (246) first presented to a hospital without tertiary paediatric surgical services, necessitating interhospital transfer. Initial colonic decompression was by rectal washouts in 86.2% (263) and by defunctioning stoma in 12.8% (39). Subsequently, 27.4% (72) of infants failed management with rectal washouts and required a delayed stoma, resulting in 36.4% (111) of infants having a stoma.

CONCLUSIONS

In this population-based cohort, presentation outside the neonatal period was rare. Nearly half of the infants with HD passed meconium within 48 hours of birth and over one third were managed with a stoma.

Resident consultant obstetrician presence on the labour ward versus other models of consultant cover: a systematic review of intrapartum outcomes

BACKGROUND

Several key policy documents have advocated 24-hour consultant obstetrician presence on the labour ward as a means of improving the safety of birth. However, it is unclear what published evidence exists comparing the outcomes of intrapartum care with 24-hour consultant labour ward presence and other models of consultant cover.

OBJECTIVES

To collate and critically appraise evidence of the effect of continuous resident consultant obstetrician cover on the labour ward on outcomes of intrapartum care compared with other models of consultant cover.

SEARCH STRATEGY

Studies were included which quantitatively compared intrapartum outcomes for women and babies where continuous resident consultant obstetric cover was provided with other models of consultant cover.

SELECTION CRITERIA

Quantitative studies within healthcare systems with mixed obstetric-midwifery models of care.

DATA COLLECTION AND ANALYSIS

Two researchers independently screened titles and full-text publications, extracted data and assessed the quality of included studies. Meta-analysis was performed using REVIEW MANAGER 5.3.

MAIN RESULTS

About 1508 publications were screened resulting in two papers, three conference abstracts and one letter being included. All were single-site time-period comparison studies. The quality of studies overall was poor with significant risk of bias. The only significant finding in meta-analysis related to instrumental deliveries, which occurred more frequently when there was on-call consultant cover (unadjusted risk ratio 1.14; 95% CI 1.04-1.24).

CONCLUSION

No reliable evidence of the effects of 24-hour resident consultant presence on the labour ward on intrapartum outcomes was identified.

TWEETABLE ABSTRACT

More robust research is needed to assess intrapartum outcomes with resident consultant labour ward presence.

Factors associated with maternal mortality at advanced maternal age: a population-based case-control study

OBJECTIVE

This study aimed to examine the factors associated with maternal mortality among women aged ≥35 years.

DESIGN

Unmatched population based case-control study.

SETTING

United Kingdom.

POPULATION

Between 2009 and 2012, 105 cases of maternal deaths aged ≥35 years were extracted from the surveillance database of the MBRRACE-UK confidential enquiries into maternal deaths in the UK. In addition, 766 controls aged ≥35 years were identified from the UK Obstetric Surveillance System (2005-2012).

METHODS

Risk factors known to be associated with maternal mortality and morbidity and for which data were available were examined for their association with maternal mortality among women ≥35 years using logistic regression analysis.

MAIN OUTCOME MEASURES

Odds ratios and 95% confidence intervals associated with maternal death.

RESULTS

Five factors were found to be significantly associated with increased odds of death among women aged ≥35 years: smoking during pregnancy (adjusted odds ratio (aOR) 2.06, 95% CI 1.13-3.75), inadequate use of antenatal care (aOR 23.62, 95% CI 8.79-63.45), medical co-morbidities (aOR 5.92, 95% CI 3.56-9.86) and previous pregnancy problems (aOR 2.06, 95% CI 1.23-3.45). The odds associated with death increased by 12% per year increase in age (aOR 1.12, 95% CI 1.02-1.22).

CONCLUSION

Age was associated with maternal mortality even after adjusting for other known risk factors. Importantly, this study showed an association between maternal mortality and smoking among women aged 35 years or older. It emphasises the importance of public health action to reduce smoking levels and address trends in rising maternal age.

TWEETABLE ABSTRACT

Smoking is a risk factor for maternal death for those aged over 35 years.

Maternal influenza and birth outcomes: systematic review of comparative studies

BACKGROUND

Although pregnant women are considered at high risk for severe influenza disease, comparative studies of maternal influenza and birth outcomes have not been comprehensively summarised.

OBJECTIVE

To review comparative studies evaluating maternal influenza disease and birth outcomes.

SEARCH STRATEGY

We searched bibliographic databases from inception to December 2014.

SELECTION CRITERIA

Studies of preterm birth, small-for-gestational-age (SGA) birth or fetal death, comparing women with and without clinical influenza illness or laboratory-confirmed influenza infection during pregnancy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently abstracted data and assessed study quality.

MAIN RESULTS

Heterogeneity across 16 studies reporting preterm birth precluded meta-analysis. In a subgroup of the highest-quality studies, two reported significantly increased preterm birth (risk ratios (RR) from 2.4 to 4.0) following severe 2009 pandemic H1N1 (pH1N1) influenza illness, whereas those assessing mild-to-moderate pH1N1 or seasonal influenza found no association. Five studies of SGA birth showed no discernible patterns with respect to influenza disease severity (pooled odds ratio 1.24; 95% CI 0.96-1.59). Two fetal death studies were of sufficient quality and size to permit meaningful interpretation. Both reported an increased risk of fetal death following maternal pH1N1 disease (RR 1.9 for mild-to-moderate disease and 4.2 for severe disease).

CONCLUSIONS

Comparative studies of preterm birth, SGA birth and fetal death following maternal influenza disease are limited in number and quality. An association between severe pH1N1 disease and preterm birth and fetal death was reported by several studies; however, these limited data do not permit firm conclusions on the magnitude of any association.

TWEETABLE ABSTRACT

Comparative studies are limited in quality but suggest severe pandemic H1N1 influenza increases preterm birth.

The Compatibility Between Biomphalaria glabrata Snails and Schistosoma mansoni: An Increasingly Complex Puzzle

This review reexamines the results obtained in recent decades regarding the compatibility polymorphism between the snail, Biomphalaria glabrata, and the pathogen, Schistosoma mansoni, which is one of the agents responsible for human schistosomiasis. Some results point to the snail's resistance as explaining the incompatibility, while others support a "matching hypothesis" between the snail's immune receptors and the schistosome's antigens. We propose here that the two hypotheses are not exclusive, and that the compatible/incompatible status of a particular host/parasite couple probably reflects the balance of multiple molecular determinants that support one hypothesis or the other. Because these genes are involved in a coevolutionary arms race, we also propose that the underlying mechanisms can vary. Finally, some recent results show that environmental factors could influence compatibility. Together, these results make the compatibility between B. glabrata and S. mansoni an increasingly complex puzzle. We need to develop more integrative approaches in order to find targets that could potentially be manipulated to control the transmission of schistosomiasis.

Pregnancy at very advanced maternal age: a UK population-based cohort study

Objectives

To describe the characteristics, management and outcomes of women giving birth at advanced maternal age (≥48 years).

Design

Population‐based cohort study using the UK Obstetric Surveillance System (UKOSS).

Setting

All UK hospitals with obstetrician‐led maternity units.

Population

Women delivering at advanced maternal age (≥48 years) in the UK between July 2013 and June 2014 (n = 233) and 454 comparison women.

Methods

Cohort and comparison group identification through the UKOSS monthly mailing.

Main outcome measures

Pregnancy complications.

Results

Older women were more likely than comparison women to be overweight (33% versus 23%, P = 0.0011) or obese (23% versus 19%, P = 0.0318), nulliparous (53% versus 44%, P = 0.0299), have pre‐existing medical conditions (44% versus 28%, P < 0.0001), a multiple pregnancy (18% versus 2%, P < 0.0001), and conceived following assisted conception (78% versus 4%, P < 0.0001). Older women appeared more likely than comparison women to have pregnancy complications including gestational hypertensive disorders, gestational diabetes, postpartum haemorrhage, caesarean delivery, iatrogenic and spontaneous preterm delivery on univariable analysis and after adjustment for demographic and medical factors. However, adjustment for multiple pregnancy or use of assisted conception attenuated most effects, with significant associations remaining only with gestational diabetes (adjusted odds ratio [aOR] 4.81, 95% CI 1.93–12.00), caesarean delivery (aOR 2.78, 95% CI 1.44–5.37) and admission to an intensive care unit (aOR 33.53, 95% CI 2.73–412.24).

Conclusions

Women giving birth at advanced maternal age have higher risks of a range of pregnancy complications. Many of the increased risks appear to be explained by multiple pregnancy or use of assisted conception.

Tweetable abstract

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

The pregnancy complications in women giving birth aged 48 or over are mostly explained by multiple pregnancy.

Maternal and perinatal outcomes in women planning vaginal birth after caesarean (VBAC) at home in England: secondary analysis of the Birthplace national prospective cohort study

OBJECTIVE

To compare vaginal birth rates in women planning vaginal birth after caesarean (VBAC) at home versus in an obstetric unit (OU) and explore transfer rates in women planning home VBAC.

DESIGN

Prospective cohort study.

SETTING

OUs and planned home births in England.

POPULATION

1436 women planning VBAC in the Birthplace cohort, including 209 planning home VBAC.

METHODS

We used Poisson regression to calculate relative risks adjusted for maternal characteristics.

MAIN OUTCOME MEASURES

MAIN OUTCOMES

(i) vaginal birth and (ii) transfer from planned home birth to OU during labour or immediately after birth.

SECONDARY OUTCOMES

(i) composite of maternal blood transfusion or admission to higher level care, (ii) stillbirth or Apgar score <7 at 5 minutes, (iii) neonatal unit admission.

RESULTS

Planned VBAC at home was associated with a statistically significant increase in the chances of having a vaginal birth compared with planned VBAC in an OU (adjusted relative risk 1.15, 95% confidence interval 1.06-1.24). The risk of an adverse maternal outcome was around 2-3% in both settings, with a similar risk of an adverse neonatal outcome. Transfer rates were high (37%) and varied markedly by parity (para 1, 56.7% versus para 2+, 24.6%).

CONCLUSION

Women in the cohort who planned VBAC at home had an increased chance of a vaginal birth compared with those planning VBAC in an OU, but transfer rates were high, particularly for women with only one previous birth, and the risk of an adverse maternal or perinatal outcome was around 2-3%. No change in guidance can be recommended.

TWEETABLE ABSTRACT

Higher vaginal birth rates in planned VBAC at home versus in OU but 2-3% adverse outcomes and high transfer rate.