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1.
Acta Obstet Gynecol Scand ; 99(7): 865-874, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31943128

RESUMO

INTRODUCTION: Late-gestation adverse pregnancy outcome is associated with reduced placental villous vascularity but rarely with a frankly abnormal umbilical artery Doppler waveform. The clinical utility of umbilical artery Doppler velocimetry in late gestation is limited by poor understanding of what aspect(s) of placental structure and function the impedance reflects. We hypothesized that placental arterial circulation impedance reflects placental vascularity and arterial function. MATERIAL AND METHODS: This was a secondary analysis of data from the FEMINA2 study, a study of pregnancy outcome after reduced fetal movement. Forty-three pregnancies that delivered within 7 days of ultrasound assessment were examined. Impedance was quantified by pulsatility index (PI) from umbilical, chorionic plate arteries, and intra-placental arteries. Site-specific PI was compared with villous vascularity (CD31 immunostaining) and placental arterial function (wire myography) by regression analysis (P < .01) where factor analysis suggested potential co-variance (Eigen value > 2). RESULTS: Pulsatility index decreased with proximity to the placental microvasculature (P < .0001). Intra-placental artery PI correlated significantly with vessel number (R2  = 0.40, P = .0007). No significant relations between umbilical or chorionic plate artery PI and villous vascularity were found (P ≥ .11 and P ≥ .042). No significant co-variance was suggested between PI at any Doppler sampling site and ex vivo placental arterial function indices. Measurement reliability (intraclass correlation coefficient) was highest in the umbilical artery (PI 0.75 and 0.50 for intra- and interoperator reliability, respectively) and lowest in the intra-placental arteries (PI 0.55 and 0.41, respectively). Systematic bias in umbilical artery PI was observed between observers, but not at other Doppler sampling sites. CONCLUSIONS: More vascular placentas ex vivo are associated with reduced intra-placental artery Doppler impedance in utero. Although umbilical (but not intra-placental) artery Doppler PI is associated with adverse outcome after reduced fetal movement, this predictive ability does not appear to be through assessment of placental vascularity or chorionic plate arterial function. The inferior reliability of intra-placental artery Doppler, although similar to previously published reliability of umbilical artery Doppler, impairs its ability to detect subtle differences in placental vascularity, and must be significantly improved before it could be considered a clinically useful test.

2.
Acta Obstet Gynecol Scand ; 99(3): 364-373, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31596942

RESUMO

INTRODUCTION: Birthweight is a critical predictor of survival in extremely early-onset fetal growth restriction (diagnosed pre-28 weeks' gestation, with abnormal umbilical/uterine artery Doppler waveforms), therefore accurate fetal weight estimation is a crucial component of antenatal management. Currently available sonographic fetal weight estimation models were predominantly developed in populations of mixed gestational age and varying fetal weights, but not specifically tested within the context of extremely early-onset fetal growth restriction. This study aimed to determine the accuracy and precision of fetal weight estimation in this population and investigate whether model performance is affected by other factors. MATERIAL AND METHODS: Cases where a growth scan was performed within 48 hours of delivery (n = 65) were identified from a cohort of extremely early-onset fetal growth-restricted pregnancies at a single tertiary maternity center (n = 159). Fetal biometry measurements were used to calculate estimated fetal weight using 21 previously published models. Systematic and random errors were calculated for each model and used to identify the best performing model, which in turn was used to explore the relationship between error and gestation, estimated fetal weight, fetal presentation, fetal asymmetry and amniotic fluid volume. RESULTS: Both systematic (median 8.2%; range -44.1 to 49.5%) and random error (median 11.6%; range 9.7-23.8%) varied widely across models. The best performing model was Hadlock head circumference-abdominal circumference-femur length (HC-AC-FL), regardless of gestational age, fetal size, fetal presentation or asymmetry, with an overall systematic error of 1.5% and random error of 9.7%. Despite this, it only calculated the estimated fetal weight within 10% of birthweight in 64.6% of cases. There was a weak negative relation between mean percentage error with Hadlock HC-AC-FL and amniotic fluid volume, suggesting fetal weight is overestimated at lower liquor volumes and underestimated at higher liquor volumes (P = 0.002, adjusted R2  = 0.08). CONCLUSIONS: Hadlock HC-AC-FL is the most accurate model currently available to estimate fetal weight in extremely early-onset fetal growth restriction independent of gestation or fetal size, asymmetry or presentation. However, for 35.4% of cases in this study, estimated fetal weight calculated using this model deviates by more than 10% from birthweight, highlighting a need for an improved model.

3.
Prenat Diagn ; 40(1): 38-48, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31306507

RESUMO

OBJECTIVE: Magnetic resonance imaging (MRI) of placental invasion has been part of clinical practice for many years. The possibility of being better able to assess placental vascularization and function using MRI has multiple potential applications. This review summarises up-to-date research on placental function using different MRI modalities. METHOD: We discuss how combinations of these MRI techniques have much to contribute to fetal conditions amenable for therapy such as singletons at high risk for fetal growth restriction (FGR) and monochorionic twin pregnancies for planning surgery and counselling for selective growth restriction and transfusion conditions. RESULTS: The whole placenta can easily be visualized on MRI, with a clear boundary against the amniotic fluid, and a less clear placental-uterine boundary. Contrasts such as diffusion weighted imaging, relaxometry, blood oxygenation level dependent MRI and flow and metabolite measurement by dynamic contrast enhanced MRI, arterial spin labeling, or spectroscopic techniques are contributing to our wider understanding of placental function. CONCLUSION: The future of placental MRI is exciting, with the increasing availability of multiple contrasts and new models that will boost the capability of MRI to measure oxygen saturation and placental exchange, enabling examination of placental function in complicated pregnancies.

4.
Eur J Obstet Gynecol Reprod Biol ; 241: 109-118, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31499415

RESUMO

BACKGROUND: Severe early-onset fetal growth restriction (FGR) predisposes to fetal death, neonatal death, neonatal morbidity and neurodisability. The use of placental biomarkers has been proposed for risk stratification in pre-eclampsia, but they could be equally useful in fetal growth restriction in aiding management. OBJECTIVE: To determine the efficacy of angiogenic biomarkers at predicting adverse pregnancy outcome in severe early-onset fetal growth restriction. STUDY DESIGN: This is a secondary analysis of the multicentre, placebo-controlled STRIDER UK randomised controlled trial of singleton pregnancies with severe early-onset fetal growth restriction. Women with FGR pregnancies between 22+0 and 29+6 weeks of gestation were randomly assigned to receive either sildenafil 25 mg three times daily or placebo until 32+0 weeks' gestation or delivery. We developed prediction models based upon maternal demographics (age, parity, blood pressure, preeclampsia, gestational hypertension), fetal biometric (estimated fetal weight) and Doppler measurements (Middle Cerebral Artery (MCA), Umbilical Artery (UA)) and maternal angiogenic biomarkers [placental growth factor (PlGF), soluble endoglin (sEng), soluble fms-like tyrosine kinase 1 (sFlt-1) and sFlt-1:PlGF ratio) using both univariate and multivariate analysis. RESULTS: A complete data set was available for 105 of 135 randomised women. Multivariate regression analysis identified estimated fetal weight (EFW) and sFlt-1:PlGF as independent predictors of livebirth (EFW OR: 1.01 (1.008, 1.021); p < 0.001 and lower sFlt-1:PlGF ratio OR: 0.53 (0.284, 0.994); p = 0.048) and overall survival (EFW OR: 1.01 (1.006, 1.015); p < 0.001 and lower sFlt-1/PlGF ratio OR: 0.51 (0.286, 0.904); p = 0.021). EFW was a consistent predictor for all outcomes other than gestation at delivery. sFlt-1:PlGF ratio was a consistent predictor for all outcomes other than neonatal morbidity. CONCLUSIONS: In severe early-onset FGR pregnancies livebirth and overall survival can be predicted using a model involving EFW and sFlt-1:PlGF ratio. This model require validation in a larger cohort but may allow informed decision making about pregnancy management, especially in previable cases.


Assuntos
Peso ao Nascer , Retardo do Crescimento Fetal , Modelos Estatísticos , Resultado da Gravidez/epidemiologia , Adulto , Biomarcadores/sangue , Feminino , Humanos , Recém-Nascido , Gravidez , Ultrassonografia Pré-Natal
5.
BMC Med Ethics ; 20(1): 56, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395047

RESUMO

BACKGROUND: Information on the factors influencing parents' decision-making process following a lethal, life-limiting or severely debilitating prenatal diagnosis remains deficient. A comprehensive systematic review and meta-synthesis was conducted to explore the influencing factors for parents considering termination or continuation of pregnancy following identification of lethal, life-limiting or severely debilitating fetal abnormalities. METHODS: Electronic searches of 13 databases were conducted. These searches were supplemented by hand-searching Google Scholar and bibliographies and citation tracing. Thomas and Harden's (2008) thematic synthesis method was used to synthesise data from identified studies. RESULTS: Twenty-four papers were identified and reviewed, but two papers were removed following quality assessment. Three main themes were identified through systematic synthesis. Theme 1, entitled 'all life is precious', described parents' perception of the importance of the fetus' life, a fatalistic view of their situation alongside moral implications as well as the implications decisions would have on their own life, in consideration of previous life experiences. Theme 2 ('hope for a positive outcome') contained two sub-themes which considered the parent's own imagined future and the influence of other people's experiences. Finally, Theme 3 ('a life worth living') presented three sub-themes which may influence their parental decision-making: These described parental consideration of the quality of life for their unborn child, the possibility of waiting to try for another pregnancy, and their own responsibilities and commitments. CONCLUSION: The first review to fully explore parental decision-making process following lethal, life-limiting, or severely debilitating prenatal diagnosis provided novel findings and insight into which factors influenced parents' decision-making process. This comprehensive and systematic review provides greater understanding of the factors influential on decision-making, such as hope, morality and potential implications on their own and other's quality of life, will enable professionals to facilitate supported decision-making, including greater knowledge of the variables likely to influence parental choices.


Assuntos
Tomada de Decisões/ética , Pais/psicologia , Diagnóstico Pré-Natal/ética , Aborto Induzido/ética , Família , Feminino , Previsões , Humanos , Gravidez
6.
Midwifery ; 76: 110-117, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31195219

RESUMO

OBJECTIVES: The research team aimed to understand women's lived experiences during pregnancies with poor prognosis following prenatal detection of Fetal Growth Restriction at the limits of viability (FGRLV). METHODS: Qualitative interviews with six women who had attended a specialist service following a prenatal diagnosis of FGRLV were conducted. The interview data were analysed using interpretative phenomenological analysis. FINDINGS: Three superordinate themes alongside thirteen subthemes were identified. Theme 1 described 'a fine line between supportive and unhelpful' care experiences. A second theme of 'understanding the situation and decisions to be made' described how women faced many uncertainties. The final theme of 'parental responsibility' reflected how women imagined their futures to have been, exploring their embodied parental role and connection to their unborn or young child. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Women highlighted the importance of maternal healthcare teams providing clear information and reassurance to them. They also reported that prior experiences were important to them in influencing their perception of that pregnancy. Furthermore, women reflected on their desperation for a positive outcome. Understanding these factors can enable maternal healthcare teams to facilitate informed decision-making and provide individualised emotional support for women. Our findings will enable maternal care teams to better support women in similar clinical situations.


Assuntos
Retardo do Crescimento Fetal/psicologia , Viabilidade Fetal , Gestantes/psicologia , Adulto , Feminino , Humanos , Entrevistas como Assunto/métodos , Acontecimentos que Mudam a Vida , Gravidez , Pesquisa Qualitativa , Medicina Estatal , Reino Unido
7.
Hum Reprod ; 34(5): 920-931, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30868153

RESUMO

STUDY QUESTION: Has birthweight (BW) changed over time among IVF-conceived singletons? SUMMARY ANSWER: Singleton BW has increased markedly over the past 25 years. WHAT IS KNOWN ALREADY: IVF conceived singletons have had a higher incidence of low BW compared to spontaneously conceived singletons, and this has raised concerns over long-term increased risks of cardio-metabolic disease. However, few causal links between IVF procedures and BW have been robustly established, and few studies have examined whether BW has changed over time as IVF techniques have developed. STUDY DESIGN, SIZE, DURATION: A total of 2780 live born singletons conceived via IVF or ICSI treated in the reproductive medicine department of a single publicly funded tertiary care centre between 1991 and 2015 were included in this retrospective study. The primary outcome measure was singleton BW adjusted for gestational age, maternal parity and child gender. Multivariable linear regression models were used to estimate the associations between patient prognostic factors and IVF treatment procedures with adjusted BW. PARTICIPANTS/MATERIALS, SETTING, METHODS: All singletons conceived at the centre following IVF/ICSI using the mother's own oocytes, and non-donated fresh or frozen/thawed embryos with complete electronic data records, were investigated. Available electronic records were retrieved from the Human Fertilization and Embryology Authority for dataset collation. Multiple linear regression analysis was used to evaluate associations between IVF treatment parameters and BW, after adjusting for the year of treatment and patient characteristics and pregnancy factors. MAIN RESULTS AND THE ROLE OF CHANCE: In the primary multivariable model, singleton BW increased by 7.4 g per year (95% CI: 3.2-11.6 g, P = 0.001), an increase of close to 180 g throughout the 25-year period after accounting for gestational age, maternal parity, child gender, IVF treatment parameters, patient prognostic characteristics and pregnancy factors. Fresh and frozen embryo transfer-conceived singletons showed a similar increase in BW. Frozen/thawed embryo transfer conceived singletons were on average 53 g heavier than their fresh embryo conceived counterparts (95% CI: 3.7-103.3 g, P = 0.035). LIMITATIONS, REASONS FOR CAUTION: The independent variables included in the study were limited to those that have been consistently recorded and stored electronically over the past two decades. WIDER IMPLICATIONS OF THE FINDINGS: There has been a progressive BW increase in IVF singletons over time in one large centre with consistent treatment eligibility criteria. Such a change is not seen in the general population of live born singletons in the UK or other developed countries, and seems to be specific to this IVF population. This may be a reflection of changes in practice such as undisturbed extended embryo culture to the blastocyst stage, optimized commercial culture media composition, single embryo transfer and ICSI. Moreover, singletons conceived from frozen/thawed embryos had higher birth weights when compared to their fresh embryo transfer counterparts. The causal pathway is unknown; however, it could be due to the impact on embryos of the freeze/thaw process, self-selection of embryos from couples who produce a surplus of embryos, and/or embryo replacement into a more receptive maternal environment. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the EU FP7 project grant, EpiHealthNet (FP7-PEOPLE-2012-ITN-317146). The authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.

9.
Placenta ; 79: 78-82, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30396518

RESUMO

The Centre for Medical Image Computing (CMIC) at University College London (UCL) hosted a two-day workshop on placenta imaging on April 12th and 13th 2018. The workshop consisted of 10 invited talks, 3 contributed talks, a poster session, a public interaction session and a panel discussion about the future direction of placental imaging. With approximately 50 placental researchers in attendance, the workshop was a platform for engineers, clinicians and medical experts in the field to network and exchange ideas. Attendees had the chance to explore over 20 posters with subjects ranging from the movement of blood within the placenta to the efficient segmentation of fetal MRI using deep learning tools. UCL public engagement specialists also presented a poster, encouraging attendees to learn more about how to engage patients and the public with their research, creating spaces for mutual learning and dialogue.


Assuntos
Placenta/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Imagem por Ressonância Magnética , Gravidez , Ultrassonografia , Microtomografia por Raio-X
10.
PLoS One ; 13(11): e0206533, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30395584

RESUMO

OBJECTIVE: To assess the value of in utero placental assessment in predicting adverse pregnancy outcome after reported reduced fetal movements (RFM). METHOD: A non-interventional prospective cohort study of women (N = 300) with subjective RFM at ≥28 weeks' gestation in singleton non-anomalous pregnancies at a UK tertiary maternity hospital. Clinical, sonographic (fetal weight, placental size and maternal, fetal and placental arterial Doppler) and biochemical (maternal serum hCG, hPL, progesterone, PlGF and sFlt-1) assessment was conducted. Multiple logistic regression identified combinations of measurements (models) most predictive of adverse pregnancy outcome (perinatal mortality, birth weight <10th centile, five minute Apgar score <7, umbilical arterial pH <7.1 or base excess <-10, neonatal intensive care admission). Models were compared by test performance characteristics (ROC curve, sensitivity, specificity, positive/negative predictive value, positive/negative likelihood ratios) against baseline care (estimated fetal weight centile, amniotic fluid index and gestation at presentation). RESULTS: 61 (20.6%) pregnancies ended in adverse outcome. Models incorporating PlGF/sFlt-1 ratio and umbilical artery free loop Doppler impedance demonstrated modest improvement in ROC area for adverse outcome (baseline care 0.69 vs. proposed models 0.73-0.76, p<0.05). However, there was little improvement in other test characteristics (baseline vs. best proposed model: sensitivity 21.7% [95% confidence interval 13.1-33.6] vs. 35.8%% [24.4-49.3], specificity 96.6% [93.4-98.3] vs. 94.7% [90.7-97.0], PPV 61.9% [40.9-79.3] vs. 63.3% [45.5-78.1], NPV 82.8% [77.9-86.8] vs. 85.2% [80.0-89.2], positive LR 6.3 [2.8-14.6] vs. 6.7 [3.4-3.3], negative LR 0.81 [0.71-0.93] vs. 0.68 [0.55-0.83]) and wide confidence intervals. Negative post-test probability remained high (16.7% vs. 14.0%). CONCLUSION: Antenatal placental assessment may improve identification of RFM pregnancies at highest risk of adverse pregnancy outcome but further work is required to understand and refine currently available outcome definitions and diagnostic techniques to improve clinical utility.


Assuntos
Movimento Fetal/fisiologia , Placenta/diagnóstico por imagem , Resultado da Gravidez , Adulto , Índice de Apgar , Estudos de Coortes , Cordocentese , Feminino , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido de Baixo Peso , Recém-Nascido , Terapia Intensiva Neonatal , Modelos Logísticos , Estudos Longitudinais , Modelos Biológicos , Morte Perinatal , Placenta/irrigação sanguínea , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Natimorto , Ultrassonografia Pré-Natal
11.
Lancet Child Adolesc Health ; 2(2): 93-102, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-30169244

RESUMO

BACKGROUND: Severe early-onset fetal growth restriction can lead to a range of adverse outcomes including fetal or neonatal death, neurodisability, and lifelong risks to the health of the affected child. Sildenafil, a phosphodiesterase type 5 inhibitor, potentiates the actions of nitric oxide, which leads to vasodilatation of the uterine vessels and might improve fetal growth in utero. METHODS: We did this superiority, placebo-controlled randomised trial in 19 fetal medicine units in the UK. We used random computer allocation (1:1) to assign women with singleton pregnancies between 22 weeks and 0 days' gestation and 29 weeks and 6 days' gestation and severe early-onset fetal growth restriction to receive either sildenafil 25 mg three times daily or placebo until 32 weeks and 0 days' gestation or delivery. We stratified women by site and by their gestational age at randomisation (before week 26 and 0 days or at week 26 and 0 days or later). We defined fetal growth restriction as a combination of estimated fetal weight or abdominal circumference below tenth percentile and absent or reversed end-diastolic blood flow in the umbilical artery on Doppler velocimetry. The primary outcome was the time from randomisation to delivery, measured in days. This study is registered with BioMed Central, number ISRCTN 39133303. FINDINGS: Between Nov 21, 2014, and July 6, 2016, we recruited 135 women and randomly assigned 70 women to sildenafil and 65 women to placebo. We found no difference in the median randomisation to delivery interval between women assigned to sildenafil (17 days [IQR 7-24]) and women assigned to placebo (18 days [8-28]; p=0·23). Livebirths (relative risk [RR] 1·06, 95% CI 0·84 to 1·33; p=0·62), fetal deaths (0·89, 0·54 to 1·45; p=0·64), neonatal deaths (1·33, 0·54 to 3·28; p=0·53), and birthweight (-14 g,-100 to 126; p=0·81) did not differ between groups. No differences were found for any other secondary outcomes. Eight serious adverse events were reported during the course of the study (six in the placebo group and two in the sildenafil group); none of these were attributed to sildenafil. INTERPRETATION: Sildenafil did not prolong pregnancy or improve pregnancy outcomes in severe early-onset fetal growth restriction and therefore it should not be prescribed for this indication outside of research studies with explicit participants' consent. FUNDING: National Institute for Health Research and Medical Research Council.


Assuntos
Retardo do Crescimento Fetal , Inibidores da Fosfodiesterase 5 , Citrato de Sildenafila , Peso ao Nascer , Método Duplo-Cego , Feminino , Retardo do Crescimento Fetal/tratamento farmacológico , Idade Gestacional , Humanos , Inibidores da Fosfodiesterase 5/uso terapêutico , Gravidez , Resultado da Gravidez , Citrato de Sildenafila/uso terapêutico , Artérias Umbilicais
12.
Nitric Oxide ; 80: 37-44, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30099096

RESUMO

Chronic hypertension in pregnancy is associated with significant adverse pregnancy outcomes, increasing the risk of pre-eclampsia, fetal growth restriction and preterm birth. Dietary nitrate, abundant in green leafy vegetables and beetroot, is reduced in vivo to nitrite and subsequently nitric oxide, and has been demonstrated to lower blood pressure, improve vascular compliance and enhance blood flow in non-pregnant humans and animals. The primary aims of this study were to determine the acceptability and efficacy of dietary nitrate supplementation, in the form of beetroot juice, to lower blood pressure in hypertensive pregnant women. In this double-blind, placebo-controlled feasibility trial, 40 pregnant women received either daily nitrate supplementation (70 mL beetroot juice, n = 20) or placebo (70 mL nitrate-depleted beetroot juice, n = 20) for 8 days. Blood pressure, cardiovascular function and uteroplacental blood flow was assessed at baseline and following acute (3 h) and prolonged (8 days) supplementation. Plasma and salivary samples were collected for analysis of nitrate and nitrite concentrations and acceptability of this dietary intervention was assessed based on questionnaire feedback. Dietary nitrate significantly increased plasma and salivary nitrate/nitrite concentrations compared with placebo juice (p < 0.001), with marked variation between women. Compared with placebo, there was no overall reduction in blood pressure in the nitrate-treated group; however there was a highly significant correlation between changes in plasma nitrite concentrations and changes in diastolic blood pressure in the nitrate-treated arm only (r = -0.6481; p = 0.0042). Beetroot juice supplementation was an acceptable dietary intervention to 97% of women. This trial confirms acceptability and potential efficacy of dietary nitrate supplementation in pregnant women. Conversion of nitrate to nitrite critically involves oral bacterial nitrate reductase activities. We speculate that differences in efficacy of nitrate supplementation relate to differences in the oral microbiome, which will be investigated in future studies.


Assuntos
Beta vulgaris , Pressão Sanguínea/efeitos dos fármacos , Sucos de Frutas e Vegetais , Hipertensão Induzida pela Gravidez/dietoterapia , Nitratos/administração & dosagem , Adulto , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Nitratos/sangue , Placebos , Gravidez , Resultado do Tratamento
13.
Acta Obstet Gynecol Scand ; 97(12): 1515-1523, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30132798

RESUMO

INTRODUCTION: Continuous fetal monitoring is used to objectively record the fetal heart rate and fetal activity over an extended period of time; however, its feasibility and acceptability to women is currently unknown. The study addressed the hypothesis that continuous fetal monitoring is feasible and acceptable to pregnant women. MATERIAL AND METHODS: Pregnant participants (n = 22) were monitored using a continuous fetal electrocardiography device, the Monica AN24. Signal quality, duration of recording and cardiotocography findings were correlated with maternal and fetal factors. Participants' change in anxiety before and after monitoring was assessed using validated questionnaires. Participants' experiences were explored through a questionnaire (n = 20) and semi-structured interview (n = 13). RESULTS: Recordings were successfully obtained in 19 of the 22 participants (86.3%). The mean recording quality of fetal heart rate was 69.0% (range 17.4%-99.4%) and maternal heart rate was 99.0% (90.9%-100.0%). Recording quality was positively correlated with gestational age (P = 0.05) and negatively correlated with uterine activity and maternal movement (P < 0.001). Overall, participants were satisfied with their experience of continuous fetal monitoring; 30% considered it preferable to intermittent monitoring. Continuous fetal monitoring did not significantly increase maternal anxiety, with a trend towards a reduction in Pregnancy Specific Anxiety score (P = 0.07). Qualitative analysis grouped women's responses into three themes: (a) reassurance and anxiety, (b) the physical device and (c) future developments in continuous fetal monitoring. CONCLUSIONS: Continuous fetal monitoring is a feasible and acceptable form of monitoring to pregnant women although further practical improvements could be incorporated. Further research is required to assess the ability of continuous fetal monitoring to detect fetal compromise.


Assuntos
Cardiotocografia/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Ansiedade/etiologia , Cardiotocografia/psicologia , Estudos de Viabilidade , Feminino , Frequência Cardíaca Fetal , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Gravidez , Pesquisa Qualitativa , Fatores de Tempo , Adulto Jovem
15.
J Physiol ; 596(23): 5523-5534, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29377190

RESUMO

The placenta is crucial for life. It is an ephemeral but complex organ acting as the barrier interface between maternal and fetal circulations, providing exchange of gases, nutrients, hormones, waste products and immunoglobulins. Many gaps exist in our understanding of the detailed placental structure and function, particularly in relation to oxygen handling and transfer in healthy and pathological states in utero. Measurements to understand oxygen transfer in vivo in the human are limited, with no general agreement on the most appropriate methods. An invasive method for measuring partial pressure of oxygen in the intervillous space through needle electrode insertion at the time of Caesarean sections has been reported. This allows for direct measurements in vivo whilst maintaining near normal placental conditions; however, there are practical and ethical implications in using this method for determination of placental oxygenation. Furthermore, oxygen levels are likely to be highly heterogeneous within the placenta. Emerging non-invasive techniques, such as MRI, and ex vivo research are capable of enhancing and improving current imaging methodology for placental villous structure and increase the precision of oxygen measurement within placental compartments. These techniques, in combination with mathematical modelling, have stimulated novel cross-disciplinary approaches that could advance our understanding of placental oxygenation and its metabolism in normal and pathological pregnancies, improving clinical treatment options and ultimately outcomes for the patient.


Assuntos
Oxigênio/metabolismo , Placenta/metabolismo , Animais , Feminino , Idade Gestacional , Humanos , Gravidez
16.
Placenta ; 64 Suppl 1: S4-S8, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29273272

RESUMO

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2017 there were four themed workshops, all of which are summarized in this report. These workshops discussed new knowledge and technological innovations in the following areas of research: 1) placental bed; 2) 3D structural modeling; 3) clinical placentology; 4) treatment of placental dysfunction.


Assuntos
Modelos Anatômicos , Doenças Placentárias/fisiopatologia , Placenta/fisiologia , Placentação/fisiologia , Feminino , Humanos , Placenta/anatomia & histologia , Doenças Placentárias/patologia , Gravidez
17.
Placenta ; 60: 1-8, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29208234

RESUMO

INTRODUCTION: Failure of trophoblast invasion and remodelling of maternal blood vessels leads to the pregnancy complication pre-eclampsia (PE). In other systems, the sphingolipid, sphingosine-1-phosphate (S1P), controls cell migration therefore this study determined its effect on extravillous trophoblast (EVT) function. METHODS: A transwell migration system was used to assess the behaviour of three trophoblast cell lines, Swan-71, SGHPL-4, and JEG3, and primary human trophoblasts in the presence or absence of S1P, S1P pathway inhibitors and 1,25(OH)2D3. QPCR and immunolocalisation were used to demonstrate EVT S1P receptor expression. RESULTS: EVTs express S1P receptors 1, 2 and 3. S1P inhibited EVT migration. This effect was abolished in the presence of the specific S1PR2 inhibitor, JTE-013 (p < 0.05 versus S1P alone) whereas treatment with the S1R1/3 inhibitor, FTY720, had no effect. In other cell types S1PR2 is regulated by vitamin D; here we found that treatment with 1,25(OH)2D3 for 48 or 72 h reduces S1PR2 (4-fold; <0.05), but not R1 and R3, expression. Moreover, S1P did not inhibit the migration of cells exposed to 1,25(OH)2D3 (p < 0.05). DISCUSSION: This study demonstrates that although EVT express three S1P receptor isoforms, S1P predominantly signals through S1PR2/Gα12/13 to activate Rho and thereby acts as potent inhibitor of EVT migration. Importantly, expression of S1PR2, and therefore S1P function, can be down-regulated by vitamin D. Our data suggest that vitamin D deficiency, which is known to be associated with PE, may contribute to the impaired trophoblast migration that underlies this condition.


Assuntos
Movimento Celular , Placentação , Receptores de Lisoesfingolipídeo/metabolismo , Trofoblastos/fisiologia , Vitamina D/fisiologia , Linhagem Celular , Feminino , Humanos , Lisofosfolipídeos/metabolismo , Gravidez , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato
18.
Acta Obstet Gynecol Scand ; 96(12): 1404-1413, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28902389

RESUMO

INTRODUCTION: Antepartum stillbirth is often preceded by detectable signs of fetal compromise, including changes in fetal heart rate and movement. It is hypothesized that continuous fetal monitoring could detect these signs more accurately and objectively than current forms of fetal monitoring and allow for timely intervention. This systematic review aimed to explore available evidence on women's experiences of continuous fetal monitoring to investigate its acceptability before clinical implementation and to inform clinical studies. MATERIAL AND METHODS: Systematic searching of four electronic databases (Embase, PsycINFO, MEDLINE and CINAHL), using key terms defined by initial scoping searches, identified a total of 35 studies. Following title and abstract screening by two independent researchers, five studies met the inclusion criteria. Studies were not excluded based on language, methodology or quality assessment. An integrative methodology was used to synthesize qualitative and quantitative data together. RESULTS: Forms of continuous fetal monitoring used included Monica AN24 monitors (n = 4) and phonocardiography (n = 1). Four main themes were identified: practical limitations of the device, negative emotions, positive perceptions, and device implementation. Continuous fetal monitoring was reported to have high levels of participant satisfaction and was preferred by women to intermittent cardiotocography. CONCLUSION: This review suggests that continuous fetal monitoring is accepted by women. However, it has also highlighted both the paucity and heterogeneity of current studies and suggests that further research should be conducted into women's experiences of continuous fetal monitoring before such devices can be used clinically.


Assuntos
Monitorização Fetal/métodos , Aceitação pelo Paciente de Cuidados de Saúde , Feminino , Humanos , Gravidez
19.
Sci Rep ; 7(1): 4144, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646147

RESUMO

Experimental methods that allow examination of the intact vascular network of large organs, such as the human placenta are limited, preventing adequate comparison of normal and abnormal vascular development in pregnancy disease. Our aims were (i) to devise an effective technique for three-dimensional analyses of human placental vessels; (ii) demonstrate the utility of the technique in the comparison of placental vessel networks in normal and fetal growth restriction (FGR) complicated pregnancies. Radiopaque plastic vessel networks of normal and FGR placentas (n = 12/group) were created by filling the vessels with resin and corroding the surrounding tissues. Subsequently, each model was scanned in a microCT scanner, reconstructed into three-dimensional virtual objects and analysed in visualisation programmes. MicroCT imaging of the models defined vessel anatomy to our analyses threshold of 100 µm diameter. Median vessel length density was significantly shorter in arterial but longer in venous FGR networks compared to normals. No significant differences were demonstrable in arterial or venous tortuosity, diameter or branch density. This study demonstrates the potential effectiveness of microCT for ex-vivo examination of human placental vessel morphology. Our findings show significant discrepancies in vessel length density in FGR placentas. The effects on fetoplacental blood flow, and hence nutrient transfer to the fetus, are unknown.


Assuntos
Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Microtomografia por Raio-X , Adulto , Biometria , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Placenta/anatomia & histologia , Placenta/patologia , Gravidez , Complicações na Gravidez/diagnóstico por imagem , Complicações na Gravidez/patologia , Microtomografia por Raio-X/métodos , Adulto Jovem
20.
Am J Obstet Gynecol ; 217(4): 453.e1-453.e12, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28651860

RESUMO

BACKGROUND: Currently, 2-dimensional ultrasound estimation of fetal size rather than fetal growth is used to define fetal growth restriction, but single estimates in late pregnancy lack sensitivity and may identify small for gestational age rather than growth restriction. Single or longitudinal measures of 3-dimensional fractional thigh volume may address this problem. OBJECTIVE: We sought to derive normal values for 3-dimensional fractional thigh volume in the third trimester, determine if fractional thigh volume is superior to 2-dimensional ultrasound biometry alone for detecting fetal growth restriction, and determine whether individualized growth assessment parameters have the potential to identify fetal growth restriction remote from term delivery. STUDY DESIGN: This was a longitudinal prospective cohort study of 115 unselected pregnancies in a tertiary referral unit (St Mary's Hospital, Manchester, United Kingdom). Standard 2-dimensional ultrasound biometry measurements were obtained, along with fractional thigh volume measurements (based on 50% of the femoral diaphysis length). Measurements were used to calculate estimated fetal weight (Hadlock). Individualized growth assessment parameters and percentage deviations in longitudinally measured biometrics were determined using a Web-based system (iGAP; http://iGAP. RESEARCH: bcm.edu). Small for gestational age was defined <10th and fetal growth restriction <3rd customized birthweight centile. Logistic regression was used to compare estimated fetal weight (Hadlock), estimated fetal weight (biparietal diameter-abdominal circumference-fractional thigh volume), fractional thigh volume, and abdominal circumference for the prediction of small for gestational age or fetal growth restriction at birth. Screening performance was assessed using area under the receiver operating characteristic curve. RESULTS: There was a better correlation between fractional thigh volume and estimated fetal weight ((biparietal diameter-abdominal circumference-fractional thigh volume) obtained at 34-36 weeks with birthweight than between 2-dimensional biometry measures such as abdominal circumference and estimated fetal weight (Hadlock). There was also a modest improvement in the detection of both small for gestational age and fetal growth restriction using fractional thigh volume-derived measures compared to standard 2-dimensional measurements (area under receiver operating characteristic curve, 0.86; 95% confidence interval, 0.79-0.94, and area under receiver operating characteristic curve, 0.92; 95% confidence interval, 0.85-0.99, respectively). CONCLUSION: Fractional thigh volume measurements offer some improvement over 2-dimensional biometry for the detection of late-onset fetal growth restriction at 34-36 weeks.


Assuntos
Diáfises/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Retardo do Crescimento Fetal/diagnóstico , Imageamento Tridimensional , Ultrassonografia Pré-Natal , Estudos de Coortes , Diáfises/crescimento & desenvolvimento , Feminino , Fêmur/crescimento & desenvolvimento , Peso Fetal , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Modelos Logísticos , Estudos Longitudinais , Gravidez , Terceiro Trimestre da Gravidez , Circunferência da Cintura
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