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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Early prediction of preeclampsia

Akolekar, Ranjit January 2016 (has links)
Preeclampsia (PE) is a major cause of perinatal and maternal morbidity and mortality. In the United Kingdom, the National Institute for Clinical Excellence (NICE) has issued guidelines on routine antenatal care recommending that at the booking visit a woman’s level of risk for PE should be determined and the subsequent intensity of antenatal care should be based on this risk assessment. This method relies on a risk scoring system derived from maternal characteristics and medical history; the performance of screening by this method is poor with detection of less than 50% of cases of preterm-PE and term-PE. The objective of this thesis is to develop a method for the estimation of the patient-specific risk for PE by combining the a priori risk based on maternal characteristics and medical history with the results of biophysical and biochemical markers obtained at 11-13 weeks’ gestation. Such early identification of high-risk pregnancies could lead to the use of pharmacological interventions, such as low-dose aspirin, which could prevent the development of the disease. The data for the thesis were derived from two types of studies: First, prospective screening in 65,771 singleton pregnancies, which provided data for maternal factors and serum pregnancy associated plasma protein-A (PAPP-A). In an unselected sequential process we also measured uterine artery pulsatility index (PI) in 45,885 of these pregnancies, mean arterial pressure (MAP) in 35,215 cases and placental growth factor (PLGF) in 14,252 cases. Second, cases-control studies for evaluating the ten most promising biochemical markers identified from search of the literature; for these studies we used stored serum or plasma samples obtained during screening and measured PLGF, Activin-A, Inhibin-A, placental protein-13 (PP13), P-selectin, Pentraxin-3 (PTX-3), soluble Endoglin (sEng), Plasminogen activator inhibitor-2 (PAI-2), Angiopoietin-2 (Ang-2) and soluble fms-like tyrosine kinase-1 (s-Flt-1). A competing risk model was developed which is based on Bayes theorem and combines the prior risk from maternal factors with the distribution of biomarkers to derive patient-specific risk for PE at different stages in pregnancy. The prior risk was derived by multiple regression analysis of maternal factors in the screening study. The distribution of biophysical and biochemical markers was derived from both the screening study and the case-control studies. The prior risk increased with advancing maternal age, increasing weight, was higher in women of Afro-Caribbean and South-Asian racial origin, those with a previous pregnancy with PE, conception by in vitro fertilization and medical history of chronic hypertension, type 1 diabetes mellitus and systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS). The estimated detection rate (DR) of PE requiring delivery at < 34, < 37 weeks’ gestation and all PE, at false positive rate (FPR) of 10%, in screening by maternal factors were 51, 43 and 40%, respectively. The addition of biochemical markers to maternal factors, including maternal serum PLGF and PAPPA, improved the performance of screening with respective DRs of 74, 56 and 41%. Similarly, addition of biophysical markers to maternal factors, including uterine artery PI and MAP, improved the performance of screening with respective DRs of 90, 72 and 57%. The combination of maternal factors with all the above biophysical and biochemical markers improved the respective DRs to 96, 77 and 54%. The findings of these studies demonstrate that a combination of maternal factors, biophysical and biochemical markers can effectively identify women at high-risk of developing PE.
2

The role of IL-33 and ST2 in early pregnancy

Alyahyaei, Zahraa January 2014 (has links)
Regulation of the growth and differentiation of trophoblast cells is critical for successful embryo implantation and placentation. Cytokines are key players in these processes, as well as modulating the maternal immune response to prevent rejection of the conceptus. This thesis focused on the investigation of the cytokine interleukin (IL) - 33 and its receptor, ST2. ST2 has two isoforms, a functional cell surface receptor (ST2L) and a soluble decoy receptor (sST2). Previous work in this laboratory had shown that the human placenta expresses both IL-33 and sST2 at term. The aim of this thesis was to investigate IL-33 and ST2 in early pregnancy, the time when trophoblast is at its most active, with a view to better understanding their role. IL-33 and ST2 mRNA and protein were examined in 14 first trimester placentas from 6-12 weeks of gestation. IL-33 was localized to cells in the villous stroma, whereas ST2 was present in the syncytiotrophoblast, villous cytotrophoblast and the invasive extravillous cytotrophoblast of the cell columns. Secretion of sST2, but not IL-33, by the placenta was found. Investigation of pre-implantation embryos showed the presence of ST2, but not IL-33 protein. Decidualized endometrium was investigated as a potential source of IL-33 and sST2 at the maternal-fetal interface and, although mRNA for both was present, no protein could be found. The key finding was that sST2, rather than ST2L, was the predominant isoform in the placenta. This led us to reconsider the hypothesis that IL-33/ST2 interactions in the placenta are important for successful pregnancy and raised the possibility that they may have independent roles. Using trophoblast cell lines as a model, it was shown that sST2 binds to trophoblast cells, significantly inhibits their proliferation and stimulates their invasion in vitro. This is the first report of this novel role for sST2 in pregnancy. Thus these studies have shown that sST2 may play an important role in implantation and placentation through controlling trophoblast invasion.
3

Risikovurdering for kromosomavvik : En kvalitativ studie om gravide kvinners tanker og erfaringer rundt denne problemstillingen / Risk assessment for chromosomal anomalies : A qualitative study of the thoughts and experiences of pregnant women regarding reaching a decision around this issue.

Aune, Ingvald January 2008 (has links)
Hensikt: Hensikten med studien er å fordype kunnskapen om hvordan gravide kvinner opplever en tidlig ultralydundersøkelse med risikovurdering for kromosomavvik, og hvordan de resonnerer omkring resultatet. Nytteverdien blir å løfte frem denne kunnskapen, og ta den med i den videre debatten omkring dette tema. Metode: Det ble gjort en kvalitativ intervjuundersøkelse med ti gravide kvinner som skulle få utført en risikovurdering for kromosomavvik. Kvinnene ble intervjuet både før og etter undersøkelsen. Grounded theory ble benyttet som analysemetode. Resultater: I studien ble det ble generert en kjernekategori; Jeg vil ha valget, men ikke ta det, og fem hovedkategorier: Eksistensielle valg, Trygghetsfølelse, Engstelse, Skyldfølelse og Veiledning / Ivaretakelse. Kjernekategorien beskriver kvinnenes konflikt mellom å ville ha muligheten til denne undersøkelsen, og samtidig ha vanskeligheter med å ta de påfølgende valgene. Noen av faktorene som gjorde valgene så vanskelige var engstelse, tap av kontroll / mestring, tilknytning til fosteret, skyldfølelse og sosialt press. Siden kvinnene ønsket selvstendige valg uten påvirkning fra andre, følte de også en større ansvarlighet for de valg som ble tatt. Forståelsen av den kalkulerte risikoen varierte mellom kvinnene, og de benyttet ulike metoder for å lette vurderingen og valget. Gravide kvinner har et stort informasjonsbehov når det gjelder prenatal diagnostikk, og de ønsker en lett tilgjengelighet til spesialisthelsetjenesten. For å få tid til refleksjon over egne verdier og holdninger, er det viktig at informasjonen blir gitt på et så tidlig tidspunkt i svangerskapet som mulig. Konklusjon: Studien viser kompleksiteten av følelser som gravide kvinner kan oppleve i forbindelse med en tidlig ultralydundersøkelse og risikovurdering for kromosomavvik. Disse stressrelaterte følelsene kan sammen med beslutninger på komplisert risikoinformasjon, og på et sterkt ansvarlig og moralsk område vanskeliggjøre beslutningsprosessen. En bedre informasjonsformidling og kontakt med helsevesenet er nødvendig for at kvinnene skal ta informerte valg, som er i tråd med deres verdier og holdninger. / Purpose: This qualitative study aimed to increase understanding of how pregnant women experience early ultrasound examination that includes risk assessment for chromosomal anomalies. Moreover, this study examined how such women rationalize test results. Method: I conducted pre- and post-examination interviews of ten pregnant women undergoing risk assessment for chromosomal anomolies, and used grounded theory to analyze the results. Results: The study generated a core category (I want a choice, but I don’t want to decide) and five main categories (existential choices, feeling of safety, anxiety, guilt, and counselling and care). Factors contributing to choice difficulty included anxiety, loss of control or coping, emotional connection to the fetus, feelings of guilt, and social pressures. The core category describes the conflict between choice and decision. Since the women sought independent choices without external influence, they also felt greater responsibility. The women’s understanding of actual risk varied, and they used different logic and methods to evaluate risk and reach a decision. Conclusion: Pregnant women need for prenatal diagnostic information and want easy access to specialty services. This study shows the complex feelings pregnant women experience regarding early ultrasound examination that includes risk assessment for chromosomal defects. Stress, non-transparent information about actual and perceived risks, and personal moral judgments further complicate the decision-making process. Therefore, improved distribution of information and frequent contact with health professionals will help women to make informed choices in accordance with their values and beliefs. / <p>ISBN 978-91-5-85721-47-4</p>
4

Identification of a rational, physiologically based early biomarker and pathogenic pathway For preeclampsia

Santillan, Mark K. 01 May 2016 (has links)
Preeclampsia is a hypertensive disorder of pregnancy that is diagnosed after the 20th week of gestation. It is defined by the American College of Obstetrics and Gynecology as de novo hypertension of at least 140/90 in a pregnant woman. Proteinuria with the hypertension is sufficient but not required for the diagnosis, especially if a woman displays severe symptoms such as headache, blurry vision, right upper quadrant pain, and low platelet count. Despite significant research, preeclampsia continues to kill 76,000 mothers and 500,000 babies per year worldwide. It causes short and long term consequences such as future metabolic and cardiovascular events for the mother and the child born during a pregnancy affected by preeclampsia. A delay in diagnosis and delayed access to appropriate care is a core cause of the preeclampsia related morbidity and severe mortality worldwide. Despite being in the medical literature since the time of the ancient Greeks, there is currently no significant predictive, preventative, therapeutic, and curative agent for preeclampsia except for an often preterm delivery of the fetus. The complex pathogenesis of preeclampsia has challenged the ability to effectively predict preeclampsia to decrease the delay in this diagnosis. Consequently, an early intervention or triage to higher level obstetric care is hindered. The lack of an early biomarker for preeclampsia also represents a major barrier to treat preeclampsia before major clinical symptoms emerge and the cycle of future cardiovascular risk for mom and baby begins. Novel, very early pregnancy predictive tests for preeclampsia may provide significant clinical utility. Furthermore, a biomarker that is linked with an early pathogenic mechanism in the first trimester development of preeclampsia would reveal a new avenue of early, first trimester intervention to treat and prevent this devastating disease. This work details the search for such a biomarker linked to an early initiator of the molecular pathogenesis of preeclampsia. These microRNA data highlight very important dysregulated mechanisms including immunologic, cell growth, and angiogenic mechanisms. T cells and the role of indoleamine 2,3 dioxygenase (IDO) is important in the early, maternal immune tolerance to the placenta and pregnancy. As poor placentation is a core cause of preeclampsia, a decreased immune tolerance to it is hypothesized to lead to preeclampsia. Furthermore, low IDO activity has been observed in the placentas of preeclamptic pregnancies which may make it a viable biomarker. These IDO-knock out mouse data, demonstrate that chronic IDO deficiency is sufficient to cause some of the core phenotypes of preeclampsia including renal dysfunction, vascular endothelial dysfunction, fetal growth restriction, and a slight increase in systolic blood pressure. This model does not completely phenocopy human preeclampsia. An investigation of early markers that are linked to vascular, immune, and renal abnormalities highlights the vasopressin pathway as a potential biomarker and early initiator of the pathogenesis of preeclampsia. These data demonstrate that copeptin, as a stable marker of vasopressin secretion, is robustly predictive of the development of late pregnancy human preeclampsia, as early as the 6th week of gestation. Furthermore, a mouse model with chronic infusion of vasopressin throughout mouse gestation phenocopies all the essential aspects of human preeclampsia: pregnancy specific hypertension, proteinuria, pathognomonic glomerular endotheliosis, fetal growth restriction, and increased fetal death. Further research must be done to elucidate the immunologic, vascular, and fetal programming phenotypes of this model. This work posits the possibility that the vasopressin pathway may provide new predictive, preventative, therapeutic, and potentially curative modalities for preeclampsia.
5

Adverse pregnancy outcomes among HIV-positive pregnant women treated with efavirenz-containing antiretroviral drugs: a retrospective cohort study in the Cape Flats

Mohammednur, Mohammedmekin Mohammedseid January 2017 (has links)
Doctor Pharmaceuticae - Dpharm / The use of efavirenz (EFV) in the first trimester of pregnancy remains controversial. In South Africa, the use of EFV-containing antiretroviral therapy (ART) as part of a Fixed Dose Combination (FDC) during the first trimester of pregnancy started in April, 2013. Literature to date has reported conflicting outcomes following the use of EFV-containing ART during the first trimester of pregnancy. The objectives of the study were to determine the prevalence of adverse pregnancy outcomes among HIV-positive pregnant women treated with EFV-containing ART and compare these results with those of pregnant women treated with NVP-containing ART and HIV-negative pregnant women in resource-limited settings. In addition, the study also aimed to determine the effect of the time of initiation of ART on the prevalence of adverse pregnancy outcomes.
6

First Trimester Depression Scores Predict Development of Gestational Diabetes Mellitus in Pregnant Rural Appalachian Women

Morrison, Chelsea, McCook, Judy G., Bailey, Beth 20 February 2015 (has links)
No description available.
7

Quantificação dos volumes do líquido amniótico e do embrião obtidos pela ultra-sonografia bidimensional e tridimensional no primeio trimestre da gestação / Quantitation of amniotic fluid and embryo volumes by two-dimensional and three-dimensional ultrasonography in the first trimester of pregnancy.

Spara, Patricia 29 September 2005 (has links)
O objetivo desse estudo foi determinar os valores do volume do líquido amniótico e do embrião, pela ultra-sonografia bidimensional e tridimensional em gestantes normais da 8ª a 11ª semana de gestação. Realizamos estudo prospectivo longitudinal em 25 fetos normais. Os critérios de inclusão foram gestações únicas, avaliação clínica e laboratorial normal e os de exclusão, gestantes portadoras de patologias maternas e/ou próprias da gestação, como também as usuárias de fumo, álcool ou drogas. Todas as pacientes assinaram o termo de consentimento esclarecido pós-informado. Os exames foram realizados por dois observadores que utilizaram aparelho ultra-songráfico modelo SA-9900 (MEDISON), transdutor endovaginal volumétrico, banda larga, de 5- 6,5 MHz, com 120 0 de campo visual. Cada gestante foi avaliadana 8ª, 9ª, 10ª e 11ª semana de gestação. O estudo bidimensional consistiu da determinação das medidas volumétricas por cálculo matemático baseado na forma do elipsóide, averiguando-se o volume do saco amniótico total e do embrião. No estudo tridimensional o volume do líquido amniótico foi feito pela técnica VOCAL. Em ambos o volume do líquido amniótico foi obtido da subtração da medida do volume do saco amniótico pela medida volumétrica do embrião. Os dados foram analisados pela análise de variância (ANOVA), correlação e análise de regressão. Em todas as análises foi utilizado como nível de significância p< 0,05. O volume do líquido amniótico (V LA ) pela ultra-sonografia bidimensional aumentou de 5,45 cm3 para 39,52 cm 3 da 8ª para a 11ª semana (ANOVA - p< 0,05). A correlação entre a idade gestacional e o volume do líquido amniótico foi forte e positiva (p< 0,001,r 2 = 88,3%). No estudo tridimensional o volume do líquido amniótico aumentou de 5,75 cm 3 para 42,96 cm 3 da 8ª para a 11 semana (ANOVA - p< 0,05). A correlação entre a idade gestacional e o volume do líquido amniótico foi forte e positiva (p< 0,001,r 2 = 98,1%). Concluindo, o volume do líquido amniótico e do embrião aumenta progressivamente da 8ª para a 11ª semana de gestação tanto na avaliação bidimensional como natridimensional. A estimativa do volume do líquido amniótico na ultra-sonografia tridimensional é menor que a bidimensional na 9ª e 10ª semana gestacional e maior na 11ª semana de gestação. O volume do embrião é maior pela técnica tridimensional do que pela bidimensional em todas as semanas gestacionais avaliadas. / The objective of this study was to determine amniotic fluid and embryo volumes by two-dimensional and three-dimensional ultrasonography in normal pregnant women from the 8th to the 11th week of gestation. We made a prospective longitudinal study on 25 normal fetuses. Inclusion criteria were singleton fetuses and normal clinical and laboratoryevaluation, and exclusion criteria were pregnant women withmaternal diseases and/or diseases typical of pregnancy, smokers, and alcohol or drug users. All patients signed an informed consent form. The tests were performed by two observers using an ultrasonography apparatus model SA-9900 (MEDISON), a volumetric endovaginal transducer, a 5-6.5 Hz broad band and 120 o of visual field. Each pregnant woman was evaluated in the8 th ,9 th , 10 th and 11 th week of gestation. The two-dimensional study consisted of the determination of volumetric measurements by a mathematical calculation based on the ellipsoid shape, with determination of total amniotic sac volume and embryo volume. In the three-dimensional study the amniotic fluid volume was determined by the VOCAL technique. In both methods, the amniotic fluid volume was obtained by subtracting the volumetric measurement of the embryo from the measurement of the amniotic sac volume. Data were analyzed statistically by analysis of variance (ANOVA), by correlation and by regression analysis, with the level of significance set at p< 0.05 in all analyses. The amniotic fluid volume (V AF ) determined by two-dimensional ultrasonography increased from 5.45 to 39.52 cm 3 from the8 th to the 11 th week (ANOVA - p< 0.05). There was a strongpositive correlation between gestational age andVAF (p< 0.001,r 2 = 88.3%). In the three-dimensional study,VAF increased from 5.75 to 42.96 cm 3 from the8 th to the 11 th week (ANOVA - p< 0.05). The correlation between gestational age andVAF was strong and positive (p< 0.001,r 2 = 98.1%). In conclusion, the volume of the amniotic fluid and of the embryo increased progressively from the 8th to the 11th week of gestation both when evaluated by two-dimensional and three-dimensional ultrasonography. The estimate ofVAF obtained by three-dimensional ultrasonography was lower than that obtained by two-dimensional ultrasonography in the 9th and 10th week of gestation and higher in the 11th week of gestation. The embryo volume obtained by the three-dimensional technique was larger than that obtained by the two-dimensional technique in all gestational weeks evaluated.
8

Ecocardiografia fetal no primeiro trimestre da gestação / First trimester fetal echocardiography

Carvalho, Sandra Regina Marques 15 December 2006 (has links)
Os objetivos deste estudo foram determinar o índice sucesso na realização de um ecocardiograma fetal completo entre a 11ª e a 14ª semanas, estabelecer a semana mais adequada para a realização de um exame completo, mensurar os diâmetros dos anéis das valvas cardíacas e comparar os diâmetros obtidos com o comprimento crânio-nádegas (CCN) correlacionando a evolução das dimensões cardíacas com o crescimento fetal nesta fase evolutiva. Avaliamos por ecocardiografia 46 fetos que apresentavam translucência nucal e avaliação Doppler do fluxo do ducto venoso normais. O estudo ecocardiográfico fetal foi realizado por via transvaginal, entre a 11ª e a 14ª semanas, com intervalos seriados de uma semana. Em cada exame, foram obtidos os três principais planos ecocardiográficos básicos e os diâmetros das valvas aórtica, pulmonar, mitral e tricúspide. As medidas dos diâmetros valvares foram comparadas ao diâmetro do CCN. Os resultados demonstraram uma taxa de sucesso na obtenção de um ecocardiograma completo de 37% na 11ª semana, de 85% na 12ª semana e de 100% entre a 13ª e a 14ª semanas. O corte mais freqüentemente obtido, nas duas primeiras semanas, foi o eixo longo e o mais difícil de ser visibilizado foi o eixo curto. As curvas de crescimento dos diâmetros das valvas mitral, tricúspide, aórtica e pulmonar demonstraram uma correlação linear com o crescimento fetal com valores de r² de 0,74, 0,75, 0,77 e 0,73. Não houve diferença estatisticamente significativa entre os diâmetros das valvas atrioventriculares e entre os diâmetros das valvas ventriculoarteriais. A obtenção dos três planos ecocardiográficos básicos em 85% dos casos na 12ª semana e 100% dos casos, a partir da 13ª semana, demonstra que é possível a realização de um ecocardiograma fetal completo no primeiro trimeste da gestação, por via transvaginal. Houve correlação positiva entre os diâmetros valvares e o CCN demonstrando uma curva de crescimento neste período. A comparação entre diâmetros valvares mitral e tricúspide, do mesmo modo que, a comparação entre os diâmetros valvares aórtico e pulmonar não apresentaram diferenças estatisticamente significativas, sugerindo não haver dominância no tamanho destas estruturas, nesta fase do desenvolvimento em fetos normais. / The aim of this study was to assess the feasibility of performing a complete echocardiography study during the first trimester of pregnancy by transvaginal approach and to establish the best week to accomplish a complete evaluation. A correlation between the measurements of the diameters of the cardiac valves and the gestational age along this period of the fetal life was made. Forty-six fetuses with normal nuchal translucency and Doppler evaluation of the venous duct were submitted to fetal echocardiography studies by transvaginal approach between the 11 and 14 weeks of gestation with a week interval. The following measurements were obtained: mitral, tricuspid, aortic and pulmonary valves diameters and the crown-rump length (CRL). The obtained results of the cardiac dimensions were compared with the CRL in the four weeks determinations. The rates of complete echocardiography evaluation were 37%, 85% and 100% at 11, 12 and 13 – 14 weeks, respectively. The longitudinal view was the easiest to obtain (100% at 12 weeks) and the short view was the most difficult one. There was no statistically significant difference between neither the diameters of the mitral and tricuspid nor the aortic and pulmonary valves. The diameters of the valves were correlated with the CRL and a linear growing curve was obtained with values of r2 of 0.74, 0.75, 0.77 and 0.73 respectively. The study demonstrated the feasibility of a complete fetal echocardiography evaluation by transvaginal approach during the first trimester of gestation. The rate of a complete evaluation increased along the period and reached 100% at 13 weeks. The longitudinal view was the easiest to obtain with a success rate of 100% at 12 week. There was a linear correlation between de cardiac valves diameters and the cranial caudal measurement revealing a relationship between the cardiac and fetal development during this phase of fetal life. The absence of statistically significant difference between the left and right valves dimensions possibly means that there is no predominance of right or left chambers during this period of evaluation.
9

Quantificação dos volumes do líquido amniótico e do embrião obtidos pela ultra-sonografia bidimensional e tridimensional no primeio trimestre da gestação / Quantitation of amniotic fluid and embryo volumes by two-dimensional and three-dimensional ultrasonography in the first trimester of pregnancy.

Patricia Spara 29 September 2005 (has links)
O objetivo desse estudo foi determinar os valores do volume do líquido amniótico e do embrião, pela ultra-sonografia bidimensional e tridimensional em gestantes normais da 8ª a 11ª semana de gestação. Realizamos estudo prospectivo longitudinal em 25 fetos normais. Os critérios de inclusão foram gestações únicas, avaliação clínica e laboratorial normal e os de exclusão, gestantes portadoras de patologias maternas e/ou próprias da gestação, como também as usuárias de fumo, álcool ou drogas. Todas as pacientes assinaram o termo de consentimento esclarecido pós-informado. Os exames foram realizados por dois observadores que utilizaram aparelho ultra-songráfico modelo SA-9900 (MEDISON), transdutor endovaginal volumétrico, banda larga, de 5- 6,5 MHz, com 120 0 de campo visual. Cada gestante foi avaliadana 8ª, 9ª, 10ª e 11ª semana de gestação. O estudo bidimensional consistiu da determinação das medidas volumétricas por cálculo matemático baseado na forma do elipsóide, averiguando-se o volume do saco amniótico total e do embrião. No estudo tridimensional o volume do líquido amniótico foi feito pela técnica VOCAL. Em ambos o volume do líquido amniótico foi obtido da subtração da medida do volume do saco amniótico pela medida volumétrica do embrião. Os dados foram analisados pela análise de variância (ANOVA), correlação e análise de regressão. Em todas as análises foi utilizado como nível de significância p< 0,05. O volume do líquido amniótico (V LA ) pela ultra-sonografia bidimensional aumentou de 5,45 cm3 para 39,52 cm 3 da 8ª para a 11ª semana (ANOVA - p< 0,05). A correlação entre a idade gestacional e o volume do líquido amniótico foi forte e positiva (p< 0,001,r 2 = 88,3%). No estudo tridimensional o volume do líquido amniótico aumentou de 5,75 cm 3 para 42,96 cm 3 da 8ª para a 11 semana (ANOVA - p< 0,05). A correlação entre a idade gestacional e o volume do líquido amniótico foi forte e positiva (p< 0,001,r 2 = 98,1%). Concluindo, o volume do líquido amniótico e do embrião aumenta progressivamente da 8ª para a 11ª semana de gestação tanto na avaliação bidimensional como natridimensional. A estimativa do volume do líquido amniótico na ultra-sonografia tridimensional é menor que a bidimensional na 9ª e 10ª semana gestacional e maior na 11ª semana de gestação. O volume do embrião é maior pela técnica tridimensional do que pela bidimensional em todas as semanas gestacionais avaliadas. / The objective of this study was to determine amniotic fluid and embryo volumes by two-dimensional and three-dimensional ultrasonography in normal pregnant women from the 8th to the 11th week of gestation. We made a prospective longitudinal study on 25 normal fetuses. Inclusion criteria were singleton fetuses and normal clinical and laboratoryevaluation, and exclusion criteria were pregnant women withmaternal diseases and/or diseases typical of pregnancy, smokers, and alcohol or drug users. All patients signed an informed consent form. The tests were performed by two observers using an ultrasonography apparatus model SA-9900 (MEDISON), a volumetric endovaginal transducer, a 5-6.5 Hz broad band and 120 o of visual field. Each pregnant woman was evaluated in the8 th ,9 th , 10 th and 11 th week of gestation. The two-dimensional study consisted of the determination of volumetric measurements by a mathematical calculation based on the ellipsoid shape, with determination of total amniotic sac volume and embryo volume. In the three-dimensional study the amniotic fluid volume was determined by the VOCAL technique. In both methods, the amniotic fluid volume was obtained by subtracting the volumetric measurement of the embryo from the measurement of the amniotic sac volume. Data were analyzed statistically by analysis of variance (ANOVA), by correlation and by regression analysis, with the level of significance set at p< 0.05 in all analyses. The amniotic fluid volume (V AF ) determined by two-dimensional ultrasonography increased from 5.45 to 39.52 cm 3 from the8 th to the 11 th week (ANOVA - p< 0.05). There was a strongpositive correlation between gestational age andVAF (p< 0.001,r 2 = 88.3%). In the three-dimensional study,VAF increased from 5.75 to 42.96 cm 3 from the8 th to the 11 th week (ANOVA - p< 0.05). The correlation between gestational age andVAF was strong and positive (p< 0.001,r 2 = 98.1%). In conclusion, the volume of the amniotic fluid and of the embryo increased progressively from the 8th to the 11th week of gestation both when evaluated by two-dimensional and three-dimensional ultrasonography. The estimate ofVAF obtained by three-dimensional ultrasonography was lower than that obtained by two-dimensional ultrasonography in the 9th and 10th week of gestation and higher in the 11th week of gestation. The embryo volume obtained by the three-dimensional technique was larger than that obtained by the two-dimensional technique in all gestational weeks evaluated.
10

Ecocardiografia fetal no primeiro trimestre da gestação / First trimester fetal echocardiography

Sandra Regina Marques Carvalho 15 December 2006 (has links)
Os objetivos deste estudo foram determinar o índice sucesso na realização de um ecocardiograma fetal completo entre a 11ª e a 14ª semanas, estabelecer a semana mais adequada para a realização de um exame completo, mensurar os diâmetros dos anéis das valvas cardíacas e comparar os diâmetros obtidos com o comprimento crânio-nádegas (CCN) correlacionando a evolução das dimensões cardíacas com o crescimento fetal nesta fase evolutiva. Avaliamos por ecocardiografia 46 fetos que apresentavam translucência nucal e avaliação Doppler do fluxo do ducto venoso normais. O estudo ecocardiográfico fetal foi realizado por via transvaginal, entre a 11ª e a 14ª semanas, com intervalos seriados de uma semana. Em cada exame, foram obtidos os três principais planos ecocardiográficos básicos e os diâmetros das valvas aórtica, pulmonar, mitral e tricúspide. As medidas dos diâmetros valvares foram comparadas ao diâmetro do CCN. Os resultados demonstraram uma taxa de sucesso na obtenção de um ecocardiograma completo de 37% na 11ª semana, de 85% na 12ª semana e de 100% entre a 13ª e a 14ª semanas. O corte mais freqüentemente obtido, nas duas primeiras semanas, foi o eixo longo e o mais difícil de ser visibilizado foi o eixo curto. As curvas de crescimento dos diâmetros das valvas mitral, tricúspide, aórtica e pulmonar demonstraram uma correlação linear com o crescimento fetal com valores de r² de 0,74, 0,75, 0,77 e 0,73. Não houve diferença estatisticamente significativa entre os diâmetros das valvas atrioventriculares e entre os diâmetros das valvas ventriculoarteriais. A obtenção dos três planos ecocardiográficos básicos em 85% dos casos na 12ª semana e 100% dos casos, a partir da 13ª semana, demonstra que é possível a realização de um ecocardiograma fetal completo no primeiro trimeste da gestação, por via transvaginal. Houve correlação positiva entre os diâmetros valvares e o CCN demonstrando uma curva de crescimento neste período. A comparação entre diâmetros valvares mitral e tricúspide, do mesmo modo que, a comparação entre os diâmetros valvares aórtico e pulmonar não apresentaram diferenças estatisticamente significativas, sugerindo não haver dominância no tamanho destas estruturas, nesta fase do desenvolvimento em fetos normais. / The aim of this study was to assess the feasibility of performing a complete echocardiography study during the first trimester of pregnancy by transvaginal approach and to establish the best week to accomplish a complete evaluation. A correlation between the measurements of the diameters of the cardiac valves and the gestational age along this period of the fetal life was made. Forty-six fetuses with normal nuchal translucency and Doppler evaluation of the venous duct were submitted to fetal echocardiography studies by transvaginal approach between the 11 and 14 weeks of gestation with a week interval. The following measurements were obtained: mitral, tricuspid, aortic and pulmonary valves diameters and the crown-rump length (CRL). The obtained results of the cardiac dimensions were compared with the CRL in the four weeks determinations. The rates of complete echocardiography evaluation were 37%, 85% and 100% at 11, 12 and 13 – 14 weeks, respectively. The longitudinal view was the easiest to obtain (100% at 12 weeks) and the short view was the most difficult one. There was no statistically significant difference between neither the diameters of the mitral and tricuspid nor the aortic and pulmonary valves. The diameters of the valves were correlated with the CRL and a linear growing curve was obtained with values of r2 of 0.74, 0.75, 0.77 and 0.73 respectively. The study demonstrated the feasibility of a complete fetal echocardiography evaluation by transvaginal approach during the first trimester of gestation. The rate of a complete evaluation increased along the period and reached 100% at 13 weeks. The longitudinal view was the easiest to obtain with a success rate of 100% at 12 week. There was a linear correlation between de cardiac valves diameters and the cranial caudal measurement revealing a relationship between the cardiac and fetal development during this phase of fetal life. The absence of statistically significant difference between the left and right valves dimensions possibly means that there is no predominance of right or left chambers during this period of evaluation.

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