431 research outputs found

    Is there still a role for nuchal translucency measurement in the changing paradigm of first trimester screening?

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    Objectives To give an overview of the genetic and structural abnormalities occurring in fetuses with nuchal translucency (NT) measurement exceeding the 95th percentile at first-trimester screening and to investigate which of these abnormalities would be missed if cell-free fetal DNA (cfDNA) were used as a first-tier screening test for chromosomal abnormalities. Methods This is a national study including 1901 pregnancies with NT &gt;= 95th percentile referred to seven university hospitals in the Netherlands between 1 January 2010 and 1 January 2016. All cases with unknown pregnancy outcome were excluded. Results of detailed ultrasound examinations, karyotyping, genotyping, pregnancy and neonatal outcomes, investigation by a clinical geneticist and post-mortem investigations were collected. Results In total, 821 (43%) pregnancies had at least one abnormality. The rate of abnormalities was 21% for fetuses with NT between 95(th) and 99(th) percentile and 62% for fetuses with NT &gt;= 99(th) percentile. Prevalence of single-gene disorders, submicroscopic, chromosomal and structural abnormalities was 2%, 2%, 30% and 9%, respectively. Conclusion Although cfDNA is superior to the combined test, especially for the detection of trisomy 21, 34% of the congenital abnormalities occurring in fetuses with increased NT may remain undetected in the first trimester of pregnancy, unless cfDNA is used in combination with fetal sonographic assessment, including NT measurement.</p

    Consequences of cervical pessary for subsequent pregnancy : follow-up of randomized clinical trial (ProTWIN)

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    Funding Information: B.W.M. is supported by a NHMRC Investigator grant (GNT1176437). B.W.M. reports consultancy for ObsEva and has received research funding from Guerbet, Ferring and Merck. The original ProTWIN trial was funded by ZonMW grant 200310004. We did not receive any funding for this followā€up research.Peer reviewedPublisher PD

    Birth weight ratio as an alternative to birth weight percentile to express infant weight in research and clinical practice: a nationwide cohort study

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    Research articleObjective. To compare birth weight ratio and birth weight percentile to express infant weight when assessing pregnancy outcome. Study Design. We performed a national cohort study. Birth weight ratio was calculated as the observed birth weight divided by the median birth weight for gestational age. The discriminative ability of birth weight ratio and birth weight percentile to identify infants at risk of perinatal death (fetal death and neonatal death) or adverse pregnancy outcome (perinatal death + severe neonatal morbidity) was compared using the area under the curve. Outcomes were expressed stratified by gestational age at delivery separate for birth weight ratio and birth weight percentile. Results. We studied 1,299,244 pregnant women, with an overall perinatal death rate of 0.62%. Birth weight ratio and birth weight percentile have equivalent overall discriminative performance for perinatal death and adverse perinatal outcome. In late preterm infants (33(+0)-36(+6) weeks), birth weight ratio has better discriminative ability than birth weight percentile for perinatal death (0.68 versus 0.63, Pā€‰ā€‰0.01) or adverse pregnancy outcome (0.67 versus 0.60, P < 0.001). Conclusion. Birth weight ratio is a potentially valuable instrument to identify infants at risk of perinatal death and adverse pregnancy outcome and provides several advantages for use in research and clinical practice. Moreover, it allows comparison of groups with different average birth weights.Bart Jan Voskamp, Brenda M. Kazemier, Ewoud Schuit, Ben Willem J. Mol, Maarten Buimer, Eva Pajkrt and Wessel Ganzevoor

    Ultrasound markers for prediction of complex gastroschisis and adverse outcome:longitudinal prospective nationwide cohort study

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    Contains fulltext : 220734.pdf (Publisherā€™s version ) (Open Access)OBJECTIVES: To identify antenatal ultrasound markers that can differentiate between simple and complex gastroschisis and assess their predictive value. METHODS: This was a prospective nationwide study of pregnancies with isolated fetal gastroschisis that underwent serial longitudinal ultrasound examination at regular specified intervals between 20 and 37 weeks' gestation. The primary outcome was simple or complex (i.e. involving bowel atresia, volvulus, perforation or necrosis) gastroschisis at birth. Fetal biometry (abdominal circumference and estimated fetal weight), the occurrence of polyhydramnios, intra- and extra-abdominal bowel diameters and the pulsatility index (PI) of the superior mesenteric artery (SMA) were assessed. Linear mixed modeling was used to compare the individual trajectories of cases with simple and those with complex gastroschisis, and logistic regression analysis was used to estimate the strength of association between the ultrasound parameters and outcome. RESULTS: Of 104 pregnancies with isolated fetal gastroschisis included, four ended in intrauterine death. Eighty-one (81%) liveborn infants with simple and 19 (19%) with complex gastroschisis were included in the analysis. We found no relationship between fetal biometric variables and complex gastroschisis. The SMA-PI was significantly lower in fetuses with gastroschisis than in healthy controls, but did not differentiate between simple and complex gastroschisis. Both intra- and extra-abdominal bowel diameters were larger in cases with complex, compared to those with simple, gastroschisis (P /= 97.7(th) percentile on at least three occasions, not necessarily on successive examinations, was associated with an increased risk of the fetus having complex gastroschisis (relative risk, 1.56 (95% CI, 1.02-2.10); P = 0.006; positive predictive value, 50.0%; negative predictive value, 81.4%). CONCLUSIONS: This large prospective longitudinal study found that intra-abdominal bowel dilatation when present repeatedly during fetal development can differentiate between simple and complex gastroschisis; however, the positive predictive value is low, and therefore the clinical usefulness of this marker is limited. (c) 2019 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology

    Enforcing Security and Safety with Proof-Carrying Code

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    AbstractIn an environment where more and more code cannot be trusted to behave safety it is becoming necessary to employ mechanisms for detecting and preventing unsafe program behavior. This paper first reviews various such mechanisms and then focuses on static mechanisms with an emphasis on Proof-Carrying Code and its expressiveness.Proof-Carrying Code is a technique that allows a code receiver to verify statically that the code has certain required properties, which are stated in the form of a safety policy. To make this possible the code is accompanied by a representation of an easily checkable formal proof of compliance with the safety policy. This paper discusses first the general properties of the Proof-Carrying Code technique and then explores a particular implementation of the idea using verification condition generators. As a surprising result we prove that by adopting such an implementation choice we limit ourselves to safety properties, which constitute but a subset (albeit a very important one) of all the interesting program properties. We further speculate on what it takes to extend Proof-Carrying Code to handle more that safety properties

    The predictive capacity of uterine artery Doppler for preterm birth - a cohort study

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    Introduction: Midā€trimester uterine artery resistance measured with Doppler sonography is predictive for iatrogenic preterm birth. In view of the emerging association between hypertensive disease in pregnancy and spontaneous preterm birth, we hypothesized that uterine artery resistance could also predict spontaneous preterm birth. Material and methods: We performed a cohort study of women with singleton pregnancies. Uterine artery resistance was routinely measured at the 18ā€22 weeks anomaly scan. Pregnancies complicated by congenital anomalies or intrauterine fetal death were excluded. We analyzed if the waveform of the uterine artery (no notch, unilateral notch or bilateral notch) was predictive for spontaneous and iatrogenic preterm birth, defined as delivery before 37 weeks of gestation. Furthermore, we assessed whether the uterine artery pulsatility index was associated with the risk of preterm birth. Results: Between January 2009 and December 2016 we collected uterine Doppler indices and relevant outcome data in 4521 women. Mean gestational age at measurement was 19+6 weeks. There were 137 (3.0%) women with a bilateral and 213 (4.7%) with a unilateral notch. Mean gestational age at birth was 38+6 weeks. Spontaneous and iatrogenic preterm birth rates were 5.7% and 4.9%, respectively. Mean uterine artery resistance was 1.12 in the spontaneous preterm birth group compared with 1.04 in the term group (P = 0.004). The risk of preterm birth was increased with high uterine artery resistance (OR 2.9 per unit; 95% CI 2.4ā€3.9). Prevalence of spontaneous preterm birth increased from 5.5% in women without a notch in the uterine arteries to 8.0% in women with a unilateral notch and 8.0% in women with a bilateral notch. For iatrogenic preterm birth, these rates were 3.9%, 13.6% and 23.4%, respectively. Likelihood ratios for the prediction of spontaneous preterm birth were 1.6 (95% CI 1.0ā€2.6) and 1.9 (95% CI 1.0ā€3.5) for unilateral and bilateral notches, respectively, and for iatrogenic preterm birth they were 3.6 (95% CI 2.5ā€5.2) and 6.8 (95% CI 4.7ā€9.9) for unilateral and bilateral notches, respectively. Of all women with bilateral notching, 31.4% delivered preterm. Conclusions: Midā€trimester uterine artery resistance measured at 18ā€22 weeks of gestation is a weak predictor of spontaneous preterm birth.Maud D. van Zijl, Bouchra Koullali, Ben W.J. Mol, Rosalinde J. Snijders, Brenda M. Kazemier, Eva Pajkr

    Change in cervical length after arrested preterm labor and the risk of preterm birth

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    ACKNOWLEDGMENTS B.W.J.M. is supported by a NHMRC Investigator grant (GNT1176437). B.W.J.M. reports consultancy for Guerbet, has been a member of the ObsEva advisory board and holds stock options for ObsEva. B.W.J.M. has received research funding from Guerbet and Merck.Peer reviewedPublisher PD

    Seeing blue: negotiating the politics of Avatar media activism

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    This thesis examines how the Hollywood blockbuster Avatar (2009) has been taken-up in media activism directed towards Indigenous struggles against imperialism. It assumes the importance of locating this phenomenon within the discursive and material regimes that mediate, enable, and constrain it. I therefore offer a contextualised analysis of the film and media relating to its appropriation, which focuses on the representational practices and structural mechanisms that inform the production, circulation, and reception of the texts. This approach emphasises the tensions and contradictions that underpin activistsā€™ relationship to the media they mobilise. Such contradictions are particularly apparent in relation to the politics of race that shape Avatar, the Indigenous activism that references it, and the media regimes that make this possible. The very forces that marginalise Indigenous voices empower auteur James Cameron to speak on their behalf and to be heard. Activists must also negotiate the tension between co-opting media spectacle and being commercialised as spectacle. However, refusing a simple critique of the representations activists deploy as media spectacles, I argue for a model that foregrounds the alliances that they seek to engender. Drawing on the work of feminist scholars Oliver (2001) and Deslandes (2010), I signal a theoretical approach that focuses on how the mediated spectator relates to such representations and insists on the spectatorā€™s responsibility to respond. Acknowledging that the tensions that animate Avatar media activism can be both constrictive and creative, this project seeks a model that maximises the potential for the latter. It thus resists the paralysis of activism that can come with critiquing how we fight for the world we imagine

    Comparison of perinatal outcome of preterm births starting in primary care versus secondary care in Netherlands: a retrospective analysis of nationwide collected data

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    Published 30 December 2014Introduction. In Netherlands, the obstetric care system is divided into primary and secondary care by risk level of the pregnancy. We assessed the incidence of preterm birth according to level of care and the association between level of care at time of labor onset and delivery and adverse perinatal outcome. Methods. Singleton pregnancies recorded in Netherlands Perinatal Registry between 1999 and 2007, with spontaneous birth between 25(+0) and 36(+6) weeks, were included. Three groups were compared: (1) labor onset and delivery in primary care; (2) labor onset in primary care and delivery in secondary care; (3) labor onset and delivery in secondary care. Multivariable logistic regression analyses were performed to calculate the risk of perinatal mortality and Apgar score ā‰¤4. Results. Of all preterm deliveries, 42% had labor onset and 7.9% had also delivery in primary care. Women with labor onset between 34(+0) and 36(+6) weeks who were referred before delivery to secondary care had the lowest risk of perinatal mortality (aOR 0.49 (0.30-0.79)). Risk of perinatal mortality (aOR 1.65; 95% CI 1.20-2.27) and low Apgar score (aOR 1.95; 95% CI 1.53-2.48) were significantly increased in preterm home delivery. Conclusion. Referral before delivery is associated with improved perinatal outcome in the occurrence of preterm labor onset in primary care.A. J. van der Ven, J. M. Schaaf, M. A. van Os, C. J. M. de Groot, M. C. Haak, E. Pajkrt, and B. W. J. Mo

    Quality assessment of ultrasonic foetal biometry during the IUGR Risk Selection (IRIS) trial: a cross sectional study

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    Objective: Intrauterine growth restriction is a major risk factor for perinatal morbidity and mortality. Ultrasonic foetal biometry is an important tool to monitor foetal growth. Therefore, the quality of these biometry scans is vital to achieve good diagnostic accuracy. We assessed the quality of foetal biometry during a nationwide trial and explored its association with sonographer's characteristics.Methods: Four scans from every sonographer (n = 154), performed at 29 and 35 weeks gestational age were collected. Two assessors scored these scans according to a national audit system. A quality score >= 65% was considered 'adequate'.We compared the quality scores per scoring criterion (i.e. foetal head measurements, abdominal circum-ference and femur length with regard to magnification, correctness of the plane and calliper placement) and gestational age. We analysed the associations between characteristics of the sonographers and their scores. In a subsample of scans of 30 sonographers we determined the interrater agreement on the quality scores given by the two assessors independently.Findings: The mean score was 81.3%. Thirteen sonographers (8.4%) failed to achieve 'adequate quality'. Scores for femur length (83.8%) were significantly higher than those for head (77.9%) and abdominal circumference (78.6%) (both P < 0.05). Scores for correctness of the plane (73.4%) were lower than those for magnification (81.2%) and calliper placement (85.7%) (both P < 0.05). Gestational age did not affect the quality scores. Only the number of scans performed in the previous year was positively associated with the scores (beta = 0.01; P < 0.05). The mean interrater difference in quality scoring was 11.1%, with 77.6% agreement on scans of 'adequate quality', but with no agreement on scans with 'insufficient quality'.Key conclusions and implications for practice: Most sonographers achieved an 'adequate quality' score. Highest quality scores were attained for femur length, lowest quality scores for the correct plane. The number of scans one performs is associated with the quality scores, yet the minimum number of scans to perform for guaranteed quality still needs to be determined. Further research is needed to develop a standardized method to assess and maintain good ultrasonic foetal biometry quality. (C) 2020 Elsevier Ltd. All rights reserved
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