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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.
151

"Estudo dopplervelocimétrico das artérias uterinas em três períodos de gestações normais" / Study of the uterine arteries Doppler ultrasound in three periods of normal pregnancies

Kathia Sakamoto 02 October 2003 (has links)
Estudo longitudinal, prospectivo, comparativo de avaliação dopplervelocimétrica das artérias uterinas direita e esquerda em 37 gestantes normais em três períodos da gestação, acompanhadas na Clínica Obstétrica do HCFMUSP. Análise da relação S/D, índice de pulsatilidade e índice de resistência, relação com o número de incisuras e com posição da placenta. Foi observada redução nos valores dos índices durante a gestação. A relação S/D AUTE com placenta a direita apresentou média superior. A incidência de incisura foi maior no período entre a 16ª e a 24ª semana de gestação. A análise da relação entre os índices dopplervelocimétricos e a presença de incisura não teve resultados significativos / Prospective, longitudinal, comparative study of Doppler evaluation of the right and left uterine arteries of 37 healthy women with singleton pregnancies, performed in three periods of pregnancy, at the Pre-Natal Care Unit HCFMUSP. S/D ratio, pulsatility index and resistance index, number of notches and placental position were analysed. A decrease in the indices was observed with advancing gestation. When placenta was on the right side, the left uterine artery S/D ratio showed increased mean values. The incidence of uterine notch was higher between the 16th and 24th week of gestation in both arteries. No correlation was found between the presence of uterine notch and the placental position
152

Valvopatia mitral em gestantes: repercusões maternas e perinatais / Maternal and perinatal events in pregnant women with mitral valve disease

Alessandra Fernandez Fernandes 05 April 2010 (has links)
Os objetivos deste estudo foram correlacionar o tipo de lesão valvar mitral com eventos maternos e neonatais. É um estudo retrospectivo, observacional, realizado na Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina de São Paulo. Foram coletados dados de 117 gestações em 111 mulheres com valvopatia mitral e 117 recém-nascidos resultantes destas gestações. No grupo estudado, foram observados 71 casos de gestantes portadoras de insuficiência mitral e 46 casos de gestantes portadoras de estenose mitral e seus 117 recém-natos. O tipo de lesão valvar, a estenose mitral, esteve significantemente relacionado piores classes funcionais (com predominância de CF III/IV), a maior necessidade de uso de medicamentos cardiovasculares, à maior freqüência de internação para compensação do quadro cardíaco, a maiores índices de parto cesárea, a menor média ponderal ao nascimento e a maior incidência de RNs pequenos para idade gestacional. Entretanto, a lesão valvar predominante não influiu com relevância estatística quanto à presença de complicações obstétricas, presença de co-morbidades clínicas, a complicações fetais, índice de Apgar < 7, e necessidade de UTI neonatal. A presença de valvopatia mitral na gravidez, principalmente a estenose mitral, acompanha-se de riscos maternos e perinatais / PURPOSE: To evaluate the maternal (clinical e obstetrical) and perinatal events related to the predominant valvar lesion in pregnant women with mitral valve disease. This is a Observational and retrospective study of 117 pregnancies in 111 patients with mitral disease, followed in a single tertiary center from January 2004 until August 2008. Clinical and obstetrical data were reviewed and analyzed according to the main type of valvar lesion (stenosis or insufficiency). The statistical analysis of the results was performed by chi-square test, Fishers exact test, and Mann-Whitney test. Among the 117 pregnancies (and neonates), there were 71 cases of predominant mitral regurgitation (MR group) and 46 with predominant mitral stenosis. The MS group presented more severe heart failure symptoms (functional class III and IV) during pregnancy, received more cardiovascular drugs and needed more hospital admissions due to cardiac reasons . Concerning perinatal events, MS presented higher rates of cesarean sections, smaller birthweight and higher incidence of SGA (small for gestational age, babies. Nevertheless, the predominant valvar lesion was not significantly related to other clinical co-morbidities, obstetrical or perinatal complications. Mitral valve disease in pregnancy is related to clinical and perinatal events, especially in patients with predominant mitral stenosis
153

Análise das repetições CA do gene IGF1, VNTR do gene da insulina e região promotora P4 do gene IGF2 em indivíduos nascidos pequenos para idade gestacional / Analysis of the CA repeats of IGF1 gene, VNTR of insulin gene polymorphism and P4 Promoter region of IGF2 gene in children born small for gestational age

Coletta, Rocio Riatto Della 22 February 2008 (has links)
Introdução: Polimorfismos na região promotora dos genes da insulina, IGF2 e IGF1 podem estar relacionados a uma diminuição da expressão desses genes na vida fetal que, por sua vez, pode causar restrição do crescimento intra-uterino e maior risco de hipospádia. Na vida pós-natal, perda completa ou parcial da expressão desses genes pode resultar em ausência de recuperação estatural e menores concentrações séricas de IGF1 na criança, além de um maior risco de diabetes melito tipo 2 e síndrome de resistência à insulina no adulto. Objetivos: Analisar em crianças nascidas pequenas para idade gestacional (PIG) com ou sem recuperação estatural (RE): 1) a freqüência alélica e genotípica dos polimorfismos VNTR-INS e das repetições CA do gene IGF1; 2) a região promotora P4 do gene IGF2; 3) a influência do VNTR INS e das repetições CA do gene IGF1 na sensibilidade à insulina e nas concentrações séricas de IGF1, respectivamente. Pacientes: Foram estudados 142 indivíduos nascidos PIG com (n= 66) e sem recuperação (n= 76) estatural selecionados de três diferentes centros (HC-FMUSP, Santa Casa de São Paulo e HC-UFPR) e um grupo controle constituído de 297 indivíduos nascidos adequados para idade gestacional (AIG). Métodos: Extração de DNA genômico; amplificação por PCR das regiões contendo os polimorfismos VNTR INS e repetições CA do IGF1 e da região promotora P4; digestão por enzima de restrição; software Genescan; seqüenciamento automático; avaliação bioquímica e hormonal da glicemia, insulina e IGF1, extração de RNA, PCR em tempo real e análise estatística com SPSS 13.0 (Statistical Package fo Social Sciences). Resultados: A média do Z-altura, Z-IMC (índice de massa corpórea), Z-altura paterno e ZEA (estatura alvo) foram maiores nas crianças PIG que tiveram recuperação estatural, com o Z-PC (perímetro cefálico) maior nas crianças sem recuperação estatural. O Z-IGF1 sérico foi significantemente mais elevado em crianças que apresentaram RE (p<0,05). A distribuição e genotipica das repetições CA do gene IGF1 e do VNTR INS foi semelhante estatisticamente entre os grupos AIG e PIG, e entre os PIG com e sem RE; não foi observada associação entre esse polimorfismo e as variáveis clínicas e laboratoriais do estudo. O estudo da região promotora P4 do gene IGF2 identificou um novo polimorfismo de 9-12 repetições C na posição -1982, antes do sítio de início de transcrição do exon 2, e este apresentou distribuição semelhante entre os grupos PIG e AIG. Foi identificada também uma troca C/T em heterozigose no nono nucleotídeo do alelo 11C em quatro crianças nascidas PIG. Contudo, a quantificação da expressão do gene IGF2 em duas dessas crianças não demonstrou perda da expressão desse gene. Conclusões: Não observamos influência dos polimorfismos acima descritos no crescimento pré e pós-natal, na presença de resistência à insulina, nem em concentrações séricas de IGF1 dos indivíduos nascidos PIG. Identificamos uma nova variante na região promotora P4 do gene IGF2, contudo estudos preliminares não demonstraram influência desse polimorfismo sobre o crescimento intra-uterino. / Introduction: Polymorphisms in the promoter region of insulin (INS), IGF2 and IGF1 genes may decrease their expression during fetal life and afterward could be related to intra-uterine fetal growth retardation and greater risk of hypospadia development. In post-natal life, decreased expression of these genes can result in lack of stature recovery and in lower IGF1 serum levels in children, as well as in higher risk for type 2 diabetes mellitus and metabolic syndrome in adults. Objectives: The aims of the present study were: (1) to analyze the allelic and the genotypic frequency of the insulin (INS) gene variable number of tandem repeats (VNTR) and the IGF1 gene CA repeats; (2) to analyze the P4 promoter region of IGF2 gene (3) to test the contribution of INS VNTR, IGF1 gene CA repeats on insulin sensitivity and IGF1 serum levels in children born SGA with and without catch up, respectively. Patients: We studied 142 individuals born SGA with catch up (n = 66) and without catch up (n = 76) selected from three different centers (HCFMUSP, Santa Casa de Sao Paulo and HC-UFPR). The control group consisted of 297 children born appropriate for gestational age (AGA). Methods: Extraction of genomic DNA, PCR-amplification of the VNTR of insulin gene, CA repeats of IGF1 and IGF2 gene P4 promoter region; restriction analysis; Genescan software; automatic sequencing. Blood measurements of serum level of glucose, insulin and IGF1. Statistical analysis (Statistical Package for Social Sciences software). Results: Regarding birth parameters, the average of Z-height, Z-BMI (body mass index) and Z-height paternal and Z- EA (target height) were higher in children born SGA who had catch up. Interestingly, we observed that the Z-PC was higher in children born SGA without catch up. In addition, the Z-IGF1 serum levels were significantly higher in children who had catch up (p <0.05). The molecular analysis of IGF1 gene CA repeats and of INS gene VNTR locus did not show a statistically significant difference in the allelic and genotypic distribution of these polymorphisms between adequate for gestational age (AGA) and SGA groups nor between SGA with and without catch up. Similarly, we have not found an association of these polymorphisms with clinical or laboratory variables of this study. A novel polymorphism in the P4 promoter region of the IGF2 gene was identified. It was characterized by cytosine repeats (9-12) at position -1982 before transcription initiation site of exon 2 of IGF2 gene. Yet, we have identified a heterozygous substitution of cytosine for thymine at the nucleotide position 9 in the allele 11C in four children born SGA. This change was also absent in the control population. Quantization of IGF2 gene expression in two of these children did show loss of expression of this gene in patients carrying the variant 9C/T. Conclusions: We have not observed an association of the above described polymorphisms with pre and post natal growth, or with the occurrence of insulin resistance in individuals born SGA. IGF-1 levels did not seem to be associated with the polymorphisms either. A new variant in the P4 promoter region of IGF2 gene was identified, however preliminary studies showed no influence on intra-uterine growth.
154

An Examination of Maternal Contributors and Potential Modifiers of Fetal Growth in Pregnancy

Ferraro, Zachary Michael 01 May 2012 (has links)
A greater understanding of critical periods of body weight regulation, including pregnancy, may aid in efforts to optimize weight management strategies for the mother and her baby. The gestational period has been implicated to play, in the child, a vital role in the developmental origins of obesity and other cardiometabolic diseases later in life. Therefore, we initially examined existing literature on the role of maternal obesity and its link to pediatric obesity and documented the known underlying physiological mechanisms responsible for this relationship while suggesting potential intervention targets that may improve maternal-fetal outcomes. In a second paper, we aimed to quantify maternal predictors of large for gestational age (LGA) neonates in the Ottawa and Kingston (OaK) birth cohort with specific hypotheses verifying the independent contribution of maternal prepregnancy body mass index (BMI) and excessive gestational weight gain (GWG) to fetal overgrowth. This paper also highlights the clinical utility of the revised 2009 Institute of Medicine GWG guidelines and discusses the potential role of physiological factors underlying the observed associations between BMI, excessive GWG and LGA neonates. As a follow-up to our population-level analysis (i.e., OAK cohort), papers three and four highlight how the insulin-like growth factor (IGF) axis, a vital regulator of growth and development, may be compromised at the molecular level in cases of maternal obesity (paper 3) and excessive GWG (paper 4). In paper 3 we show that maternal obesity is associated with attenuated expression of IGF binding protein-4 (IGFBP4) in umbilical cord blood and discuss how this may preferentially promote fetal adipogenesis. The effects of excessive GWG on IGF axis protein expression are addressed in paper four where we show that excessive weight gain during pregnancy is associated with increased expression of IGFBP3 in maternal circulation in normoglycemic term pregnancies. In this paper we discuss the potential inhibitory role of IGFBP3 on adipogenesis and how it relates to glucose intolerance during pregnancy. Recognizing that both obesity and excessive GWG can alter physiological processes in mother and her baby, appropriate evidence-based interventions are warranted to best optimize outcomes. In paper five, we discuss the results of a study which sought to assess patient information channels and knowledge of nutrition and physical activity during pregnancy with the intent that these findings be applied to best design efficacious strategies that cater to the needs of our target group of pregnant women. In our analysis we show that the majority of pregnant women studied would be willing to participate in a lifestyle intervention for their own personal health and that of their child. Of great interest was the observation that most women were not informed of the importance of pregnancy-specific energy intake, or made aware of their own healthy GWG targets. Additionally, many of the respondents reported receiving no information pertaining to appropriate physical activity recommendations; despite the fact that the vast majority of participants consider this lifestyle modality to be safe during their pregnancy. Finally in paper six, we build on the results of our previous work and evaluate the risks and benefits of physical activity during pregnancy on maternal-fetal outcomes through a review of the literature and note that engaging in non-sedentary pursuits during gestation may aid in maternal weight regulation, protect against metabolic disorders and optimize neonatal birth weight and body composition. Overall, the collective nature of the papers presented in this dissertation provides qualitative and quantitative evidence to support not only the complexity of body weight regulation in the mother and her baby, but also highlights potential avenues for intervention that may improve maternal-fetal outcomes during this critical period.
155

Asthma during Pregnancy

Firoozi, Faranak 11 1900 (has links)
L’asthme est connu comme l’une des maladies chroniques les plus fréquentes chez la femme enceinte avec une prévalence de 4 à 8%. La prévalence élevée de l’asthme fait en sorte qu’on se préoccupe de l’impact de la grossesse sur l’asthme et de l’impact de l’asthme sur les issus de la grossesse. La littérature présente des résultats conflictuels concernant l’impact de l’asthme maternel sur les issus périnatales comme les naissances prématurées, les bébés de petit poids et les bébés de petit poids pour l’âge gestationnel (PPGA). De plus, les données scientifiques sont rares concernant l’impact de la sévérité et de la maîtrise de l’asthme durant la grossesse sur les issus périnatales. Donc, nous avons mené cinq études pour réaliser les objectifs suivants: 1. Le développement et la validation de deux indexes pour mesurer la sévérité et la maîtrise de l’asthme. 2. L’évaluation de l’impact du sexe du fœtus sur le risque d’exacerbation de l’asthme maternel et l’utilisation de médicaments antiasthmatiques durant la grossesse; 3. L’évaluation de l’impact de l’asthme maternel sur les issus périnatales; 4. L’évaluation de l’impact de la sévérité de l’asthme maternel durant la grossesse sur les issus périnatales; 5. L’évaluation de l’impact de la maîtrise de l’asthme maternel durant la grossesse sur les issus périnatales. Pour réaliser ces projets de recherche, nous avons travaillé avec une large cohorte de grossesse reconstruite à partir du croisement de trois banques de données administratives du Québec recouvrant la période entre 1990 et 2002. Pour les trois dernières études, nous avons utilisé un devis de cohorte à deux phases d’échantillonnage pour obtenir, à l’aide d’un questionnaire postal, des informations complémentaires qui ne se trouvaient pas dans les banques de données, comme la consommation de cigarettes et d’alcool pendant la grossesse. Nous n’avons trouvé aucune différence significative entre les mères de fétus féminins et de fétus masculins pour les exacerbations de l’asthme pendant la grossesse (aRR=1.02; IC 95%: 0.92 to 1.14). Par contre, nous avons trouvé que le risque de bébé PPGA (OR: 1.27, IC 95%: 1.14-1.41), de bébé de petit poids (OR: 1.41, IC 95%:1.22-1.63) et de naissance prématurée (OR: 1.64, IC 95%:1.46-1.83) était significativement plus élevés chez les femmes asthmatiques que chez les femmes non asthmatiques. De plus, nous avons démontré que le risque d’un bébé PPAG était significativement plus élevé chez les femmes avec un asthme sévère (OR:1.48, IC 95%: 1.15-1.91) et modéré (OR: 1.30, IC 95%:1.10-1.55) que chez les femmes qui avaient un asthme léger. Nous avons aussi observé que les femmes qui avaient un asthme bien maîtrisé durant la grossesse étaient significativement plus à risque d’avoir un bébé PPAG (OR:1.28, IC 95%: 1.15-1.43), un bébé de petit poids (OR: 1.42, IC 95%:1.22-1.66), et un bébé prématuré (OR: 1.63, IC 95%:1.46-1.83) que les femmes non asthmatiques. D’après nos résultats, toutes les femmes asthmatiques même celles qui ont un asthme bien maîtrisé doivent être suivies de près durant la grossesse car elles courent un risque plus élevé d’avoir des issus de grossesses défavorables pour leur nouveau-né. / Asthma is known as one of the most frequent chronic diseases encountered during pregnancy with prevalence estimated between 4 and 8%. The high prevalence of asthma during pregnancy results in some concerns about the impact of pregnancy on maternal asthma and also the impact of maternal asthma on perinatal outcomes. The literature presents conflicting results concerning the impact of maternal asthma during pregnancy on perinatal outcomes, such as preterm birth, low-birth-weight (LBW) infant and small-for-gestational-age (SGA) infant. Also, scientific evidence is scarce regarding the impact of asthma severity and control during pregnancy on these perinatal outcomes. We thus conducted a research project composed of five studies to achieve the following objectives: 1. to develop and validate two database indexes, one to measure the control of asthma and the other to measure asthma severity; 2. to evaluate the effect of fetal gender on maternal asthma exacerbations and the use of asthma medications during pregnancy; 3. to evaluate the impact of maternal asthma on adverse perinatal outcomes; 4. to evaluate the impact of the severity of asthma during pregnancy on adverse perinatal outcomes; 5. to evaluate the impact of adequately controlled maternal asthma during pregnancy on adverse perinatal outcomes. A large population-based cohort was reconstructed through the linking of three of Quebec’s (Canada) administrative databases covering the period between 1990 and 2002. A two-stage sampling cohort design was used to collect additional information on the women’s life-style habits by way of a mailed questionnaire for the three last studies. We have observed no significant differences between mothers of a female and male fetus as to the occurrence of asthma exacerbations (aRR=1.02; 95% CI: 0.92 to 1.14). We have found that the risk of SGA (OR: 1.27, 95% CI: 1.14-1.41), LBW (OR: 1.41, 95% CI:1.22-1.63) and preterm delivery (OR: 1.64, 95%CI:1.46-1.83) was significantly higher among asthmatic than non-asthmatic women. Moreover, our results showed that the risk of SGA was significantly higher among severe (OR:1.48, 95%CI: 1.15-1.91) and moderate asthmatic women (OR: 1.30, 95%CI:1.10-1.55) than mild asthmatic women. Also, mothers with adequately controlled asthma during pregnancy were found to be at higher risk of adverse perinatal outcomes than non-asthmatic women (SGA (OR:1.28, 95%CI: 1.15-1.43), LBW (OR: 1.42, 95%CI:1.22-1.66), and preterm deliveries (OR: 1.63, 95%CI:1.46-1.83)). According to our results, all asthmatic women even those with adequately controlled asthma should be closely monitored during pregnancy because they are at increased risk of adverse perinatal outcomes.
156

An Examination of Maternal Contributors and Potential Modifiers of Fetal Growth in Pregnancy

Ferraro, Zachary Michael 01 May 2012 (has links)
A greater understanding of critical periods of body weight regulation, including pregnancy, may aid in efforts to optimize weight management strategies for the mother and her baby. The gestational period has been implicated to play, in the child, a vital role in the developmental origins of obesity and other cardiometabolic diseases later in life. Therefore, we initially examined existing literature on the role of maternal obesity and its link to pediatric obesity and documented the known underlying physiological mechanisms responsible for this relationship while suggesting potential intervention targets that may improve maternal-fetal outcomes. In a second paper, we aimed to quantify maternal predictors of large for gestational age (LGA) neonates in the Ottawa and Kingston (OaK) birth cohort with specific hypotheses verifying the independent contribution of maternal prepregnancy body mass index (BMI) and excessive gestational weight gain (GWG) to fetal overgrowth. This paper also highlights the clinical utility of the revised 2009 Institute of Medicine GWG guidelines and discusses the potential role of physiological factors underlying the observed associations between BMI, excessive GWG and LGA neonates. As a follow-up to our population-level analysis (i.e., OAK cohort), papers three and four highlight how the insulin-like growth factor (IGF) axis, a vital regulator of growth and development, may be compromised at the molecular level in cases of maternal obesity (paper 3) and excessive GWG (paper 4). In paper 3 we show that maternal obesity is associated with attenuated expression of IGF binding protein-4 (IGFBP4) in umbilical cord blood and discuss how this may preferentially promote fetal adipogenesis. The effects of excessive GWG on IGF axis protein expression are addressed in paper four where we show that excessive weight gain during pregnancy is associated with increased expression of IGFBP3 in maternal circulation in normoglycemic term pregnancies. In this paper we discuss the potential inhibitory role of IGFBP3 on adipogenesis and how it relates to glucose intolerance during pregnancy. Recognizing that both obesity and excessive GWG can alter physiological processes in mother and her baby, appropriate evidence-based interventions are warranted to best optimize outcomes. In paper five, we discuss the results of a study which sought to assess patient information channels and knowledge of nutrition and physical activity during pregnancy with the intent that these findings be applied to best design efficacious strategies that cater to the needs of our target group of pregnant women. In our analysis we show that the majority of pregnant women studied would be willing to participate in a lifestyle intervention for their own personal health and that of their child. Of great interest was the observation that most women were not informed of the importance of pregnancy-specific energy intake, or made aware of their own healthy GWG targets. Additionally, many of the respondents reported receiving no information pertaining to appropriate physical activity recommendations; despite the fact that the vast majority of participants consider this lifestyle modality to be safe during their pregnancy. Finally in paper six, we build on the results of our previous work and evaluate the risks and benefits of physical activity during pregnancy on maternal-fetal outcomes through a review of the literature and note that engaging in non-sedentary pursuits during gestation may aid in maternal weight regulation, protect against metabolic disorders and optimize neonatal birth weight and body composition. Overall, the collective nature of the papers presented in this dissertation provides qualitative and quantitative evidence to support not only the complexity of body weight regulation in the mother and her baby, but also highlights potential avenues for intervention that may improve maternal-fetal outcomes during this critical period.
157

Análise das repetições CA do gene IGF1, VNTR do gene da insulina e região promotora P4 do gene IGF2 em indivíduos nascidos pequenos para idade gestacional / Analysis of the CA repeats of IGF1 gene, VNTR of insulin gene polymorphism and P4 Promoter region of IGF2 gene in children born small for gestational age

Rocio Riatto Della Coletta 22 February 2008 (has links)
Introdução: Polimorfismos na região promotora dos genes da insulina, IGF2 e IGF1 podem estar relacionados a uma diminuição da expressão desses genes na vida fetal que, por sua vez, pode causar restrição do crescimento intra-uterino e maior risco de hipospádia. Na vida pós-natal, perda completa ou parcial da expressão desses genes pode resultar em ausência de recuperação estatural e menores concentrações séricas de IGF1 na criança, além de um maior risco de diabetes melito tipo 2 e síndrome de resistência à insulina no adulto. Objetivos: Analisar em crianças nascidas pequenas para idade gestacional (PIG) com ou sem recuperação estatural (RE): 1) a freqüência alélica e genotípica dos polimorfismos VNTR-INS e das repetições CA do gene IGF1; 2) a região promotora P4 do gene IGF2; 3) a influência do VNTR INS e das repetições CA do gene IGF1 na sensibilidade à insulina e nas concentrações séricas de IGF1, respectivamente. Pacientes: Foram estudados 142 indivíduos nascidos PIG com (n= 66) e sem recuperação (n= 76) estatural selecionados de três diferentes centros (HC-FMUSP, Santa Casa de São Paulo e HC-UFPR) e um grupo controle constituído de 297 indivíduos nascidos adequados para idade gestacional (AIG). Métodos: Extração de DNA genômico; amplificação por PCR das regiões contendo os polimorfismos VNTR INS e repetições CA do IGF1 e da região promotora P4; digestão por enzima de restrição; software Genescan; seqüenciamento automático; avaliação bioquímica e hormonal da glicemia, insulina e IGF1, extração de RNA, PCR em tempo real e análise estatística com SPSS 13.0 (Statistical Package fo Social Sciences). Resultados: A média do Z-altura, Z-IMC (índice de massa corpórea), Z-altura paterno e ZEA (estatura alvo) foram maiores nas crianças PIG que tiveram recuperação estatural, com o Z-PC (perímetro cefálico) maior nas crianças sem recuperação estatural. O Z-IGF1 sérico foi significantemente mais elevado em crianças que apresentaram RE (p<0,05). A distribuição e genotipica das repetições CA do gene IGF1 e do VNTR INS foi semelhante estatisticamente entre os grupos AIG e PIG, e entre os PIG com e sem RE; não foi observada associação entre esse polimorfismo e as variáveis clínicas e laboratoriais do estudo. O estudo da região promotora P4 do gene IGF2 identificou um novo polimorfismo de 9-12 repetições C na posição -1982, antes do sítio de início de transcrição do exon 2, e este apresentou distribuição semelhante entre os grupos PIG e AIG. Foi identificada também uma troca C/T em heterozigose no nono nucleotídeo do alelo 11C em quatro crianças nascidas PIG. Contudo, a quantificação da expressão do gene IGF2 em duas dessas crianças não demonstrou perda da expressão desse gene. Conclusões: Não observamos influência dos polimorfismos acima descritos no crescimento pré e pós-natal, na presença de resistência à insulina, nem em concentrações séricas de IGF1 dos indivíduos nascidos PIG. Identificamos uma nova variante na região promotora P4 do gene IGF2, contudo estudos preliminares não demonstraram influência desse polimorfismo sobre o crescimento intra-uterino. / Introduction: Polymorphisms in the promoter region of insulin (INS), IGF2 and IGF1 genes may decrease their expression during fetal life and afterward could be related to intra-uterine fetal growth retardation and greater risk of hypospadia development. In post-natal life, decreased expression of these genes can result in lack of stature recovery and in lower IGF1 serum levels in children, as well as in higher risk for type 2 diabetes mellitus and metabolic syndrome in adults. Objectives: The aims of the present study were: (1) to analyze the allelic and the genotypic frequency of the insulin (INS) gene variable number of tandem repeats (VNTR) and the IGF1 gene CA repeats; (2) to analyze the P4 promoter region of IGF2 gene (3) to test the contribution of INS VNTR, IGF1 gene CA repeats on insulin sensitivity and IGF1 serum levels in children born SGA with and without catch up, respectively. Patients: We studied 142 individuals born SGA with catch up (n = 66) and without catch up (n = 76) selected from three different centers (HCFMUSP, Santa Casa de Sao Paulo and HC-UFPR). The control group consisted of 297 children born appropriate for gestational age (AGA). Methods: Extraction of genomic DNA, PCR-amplification of the VNTR of insulin gene, CA repeats of IGF1 and IGF2 gene P4 promoter region; restriction analysis; Genescan software; automatic sequencing. Blood measurements of serum level of glucose, insulin and IGF1. Statistical analysis (Statistical Package for Social Sciences software). Results: Regarding birth parameters, the average of Z-height, Z-BMI (body mass index) and Z-height paternal and Z- EA (target height) were higher in children born SGA who had catch up. Interestingly, we observed that the Z-PC was higher in children born SGA without catch up. In addition, the Z-IGF1 serum levels were significantly higher in children who had catch up (p <0.05). The molecular analysis of IGF1 gene CA repeats and of INS gene VNTR locus did not show a statistically significant difference in the allelic and genotypic distribution of these polymorphisms between adequate for gestational age (AGA) and SGA groups nor between SGA with and without catch up. Similarly, we have not found an association of these polymorphisms with clinical or laboratory variables of this study. A novel polymorphism in the P4 promoter region of the IGF2 gene was identified. It was characterized by cytosine repeats (9-12) at position -1982 before transcription initiation site of exon 2 of IGF2 gene. Yet, we have identified a heterozygous substitution of cytosine for thymine at the nucleotide position 9 in the allele 11C in four children born SGA. This change was also absent in the control population. Quantization of IGF2 gene expression in two of these children did show loss of expression of this gene in patients carrying the variant 9C/T. Conclusions: We have not observed an association of the above described polymorphisms with pre and post natal growth, or with the occurrence of insulin resistance in individuals born SGA. IGF-1 levels did not seem to be associated with the polymorphisms either. A new variant in the P4 promoter region of IGF2 gene was identified, however preliminary studies showed no influence on intra-uterine growth.
158

An Examination of Maternal Contributors and Potential Modifiers of Fetal Growth in Pregnancy

Ferraro, Zachary Michael January 2012 (has links)
A greater understanding of critical periods of body weight regulation, including pregnancy, may aid in efforts to optimize weight management strategies for the mother and her baby. The gestational period has been implicated to play, in the child, a vital role in the developmental origins of obesity and other cardiometabolic diseases later in life. Therefore, we initially examined existing literature on the role of maternal obesity and its link to pediatric obesity and documented the known underlying physiological mechanisms responsible for this relationship while suggesting potential intervention targets that may improve maternal-fetal outcomes. In a second paper, we aimed to quantify maternal predictors of large for gestational age (LGA) neonates in the Ottawa and Kingston (OaK) birth cohort with specific hypotheses verifying the independent contribution of maternal prepregnancy body mass index (BMI) and excessive gestational weight gain (GWG) to fetal overgrowth. This paper also highlights the clinical utility of the revised 2009 Institute of Medicine GWG guidelines and discusses the potential role of physiological factors underlying the observed associations between BMI, excessive GWG and LGA neonates. As a follow-up to our population-level analysis (i.e., OAK cohort), papers three and four highlight how the insulin-like growth factor (IGF) axis, a vital regulator of growth and development, may be compromised at the molecular level in cases of maternal obesity (paper 3) and excessive GWG (paper 4). In paper 3 we show that maternal obesity is associated with attenuated expression of IGF binding protein-4 (IGFBP4) in umbilical cord blood and discuss how this may preferentially promote fetal adipogenesis. The effects of excessive GWG on IGF axis protein expression are addressed in paper four where we show that excessive weight gain during pregnancy is associated with increased expression of IGFBP3 in maternal circulation in normoglycemic term pregnancies. In this paper we discuss the potential inhibitory role of IGFBP3 on adipogenesis and how it relates to glucose intolerance during pregnancy. Recognizing that both obesity and excessive GWG can alter physiological processes in mother and her baby, appropriate evidence-based interventions are warranted to best optimize outcomes. In paper five, we discuss the results of a study which sought to assess patient information channels and knowledge of nutrition and physical activity during pregnancy with the intent that these findings be applied to best design efficacious strategies that cater to the needs of our target group of pregnant women. In our analysis we show that the majority of pregnant women studied would be willing to participate in a lifestyle intervention for their own personal health and that of their child. Of great interest was the observation that most women were not informed of the importance of pregnancy-specific energy intake, or made aware of their own healthy GWG targets. Additionally, many of the respondents reported receiving no information pertaining to appropriate physical activity recommendations; despite the fact that the vast majority of participants consider this lifestyle modality to be safe during their pregnancy. Finally in paper six, we build on the results of our previous work and evaluate the risks and benefits of physical activity during pregnancy on maternal-fetal outcomes through a review of the literature and note that engaging in non-sedentary pursuits during gestation may aid in maternal weight regulation, protect against metabolic disorders and optimize neonatal birth weight and body composition. Overall, the collective nature of the papers presented in this dissertation provides qualitative and quantitative evidence to support not only the complexity of body weight regulation in the mother and her baby, but also highlights potential avenues for intervention that may improve maternal-fetal outcomes during this critical period.
159

The association between levels of fish consumption early in pregnancy and birth outcomes of pregnant women in Johannesburg, South Africa

Alawode, Oluwatoyin Wumi 06 1900 (has links)
Background: Neonates born with low birth weight or preterm are at an increased risk of long-term adverse health outcomes. Research studies on the association of fish consumption during pregnancy and birth outcomes, have led to inconsistent conclusions. Maternal dietary intakes during pregnancy have a significant impact on foetal development and growth. The aim of this project is to determine levels of maternal fish intake at <18 weeks during pregnancy and to determine the association with birth outcomes in pregnant women from Johannesburg, South Africa. Methods: This Master‘s study is nested in a larger study with a longitudinal observational research design was conducted on 250 pregnant women in Johannesburg, South Africa. For this Master‘s study, data from the first 102 participants were used. Data for this study were collected early in pregnancy (<18 week‘s gestation) and at birth. The birth data were collected by the study mid-wife. Maternal fish consumption during early pregnancy was measured using a Quantitative Food Frequency Questionnaire (QFFQ). Correlation analysis was used to examine the association between maternal fish consumption during early pregnancy and neonatal anthropometry (birth weight, crown heel length and head circumference) and gestational age at birth. Results: Majority (88.1%) of the mothers were black South Africans between the ages of 18 and 39 with a mean age of 28 ± 5 years. At enrolment, the mean BMI of the women was 27.8±5.8kg/m2 having a mean height of 158.8±6.7cm and a mean weight of 70.4±15.2kg. Most of them were unmarried (45.4%), living in households of 2 – 5 members (86.3%), wage-earning (44.6%) and had Grade 11 or 12 schooling (58.4%). Most (76.5%) of the pregnant women consumed fish rarely (once a month) and the overall median fish intake was 4.8g/day (0; 25). In the study sample 12.5% of new-borns had a low birth weight (<2500g), the percentages of preterm births were 1.0% - extremely preterm (<28 weeks), 2.0% - very preterm (28 – <32 weeks) and 10.0% - moderate to late preterm (32 – 37 weeks). The mean birth weight was 2999.2±624.4g with boys having a mean birth weight of 3157.3±571g and girls at 2819±671g. The new-borns‘ mean gestational age at birth was 38.8±2.4weeks (271.6days). The percentage of new-born head circumference ≤ 31.49cm was 9.2% and the mean head circumference was 34.3±3.6cm with the boys having a mean head circumference of 34.5±2.4cm and the girls 34.1±4.3cm. In this study sample, 3.7% of new-borns were born with crown heel length of 31 – 40cm and the mean crown heel length mean was 49.5±4.6cm with the boys having a mean crown heel length of 49.8±4.9cm and the girls having mean crown heel length of 49.3±4.3cm. In this study, there were no statistically significant associations between fish consumption at early pregnancy and birth outcomes such as gestational age at birth (r=0.051; p=0.625), birth weight (r=-0.043; p=0.695) and crown heel length (r=0.008; p=0.943). There was a positive association between maternal fish consumption in early pregnancy and head circumference of the new-born which tended towards statistical significance (r=0.193; p=0.079). Conclusions: In this study of pregnant women living in Johannesburg, a few women consumed fish at early pregnancy compared with women who did not consume fish during pregnancy. We found no statistically significant association in this study between fish consumption at early pregnancy and birth outcomes. / Life and Consumer Sciences / MCS (Consumer Science)
160

Les méthodes de procréation médicale assistées et les risques adverses périnataux : l’impact du programme de remboursement universel du Québec.

Gorgui, Jessica 12 1900 (has links)
L'infertilité affecte 11-15 % des Canadiennes et 8-20 % des couples ont de la difficulté à concevoir spontanément. Par conséquent, le recours à la procréation médicalement assistée (PMA) ne cesse d'augmenter, cependant la controverse demeure quant à ses risques sur la santé maternelle et celle des enfants. La PMA comprend les techniques de procréation assistée (TRA) (fécondation in vitro [FIV], insémination intra-utérine [IIU]) et les stimulateurs ovariens (SO), avec plus de 5 millions d'enfants issu d’une FIV au monde. La PMA a précédemment été associée à un risque accru d’issues adverses de grossesse incluant l’hypertension gestationnelle, les saignements utérins ainsi que les issues adverses affectant la santé de l’enfant, notamment les grossesses multiples, la prématurité, et le faible poids à la naissance sur lesquelles nous allons nous concentrer dans cette thèse de doctorat. Entre 05/08/2010-15/11/2015, le Québec fut la 1ère province Canadienne à financer un programme de remboursement universel pour la PMA, visant à augmenter le taux de natalité au Québec et réduire les grossesses multiples et leurs dépenses de santé associées en implémentant le transfert d'embryon unique. Le programme a été interrompu en 2015 dû aux dépenses de santé plus élevées que prévu. Nous avons identifié plusieurs lacunes de connaissances, que nous avons cherché à combler dans ce programme doctoral. Premièrement, aucun registre n’a été mis en place pour évaluer l'impact du programme sur les mères et les enfants. Deuxièmement, les études se concentrent sur les TRA ou combinent toutes les méthodes non-FIV, ce qui a des implications cliniques limitées. Les SO sont sous-analysées mais ont des implications cliniques importantes car ils constituent un traitement de première ligne pour l'infertilité. Enfin, les grossesses singleton sont moins évaluées alors qu’il est devenu évident qu'elles comportent des risques périnataux cliniquement importants. Cette thèse de doctorat est composée d'une revue de la littérature publiée et de trois études épidémiologiques effectuées dans la Cohorte des Grossesses du Québec (CQG). L'étude 1 quantifie les variations des tendances trimestrielles des issues obstétricales et périnatales 5 ans avant et pendant le programme québécois, et quantifie le risque de multiplicité associé au programme et à la PMA dans l’ensemble et par sous-types (SO seuls, TRA seuls, SO/TRA combinés) pendant ses années actives. Nous avons aussi étudié le rôle des grossesses multiples comme modificateur d'effet dans l'association entre la PMA et la prématurité. Entre 2005-2015, nous avons observé une augmentation de la prévalence de multiplicité par un facteur de 10. Les grossesses multiples ont augmenté significativement pendant le programme (rapport de cotes ajusté [RCa] 6,09, intervalle de confiance à 95 % [IC95%] 5,23-7,09) par rapport aux 5 ans avant. La PMA a significativement augmenté le risque de multiplicité (RCa 4,65, IC95% 3,84-5,62) par rapport à la conception spontanée. Les SO seuls augmentaient le plus le risque de multiplicité (RCa 6,28, IC95 % 4,56-8,64) par rapport à la conception spontanée. L’étude 2 quantifie le risque de prématurité associé à la PMA dans l'ensemble et par sous-type parmi les grossesses singleton survenues pendant le programme et dans une cohorte restreinte de grossesses PMA pour évaluer l'impact d’un biais d'indication (l’infertilité ou la sous-fertilité) potentiel. La PMA dans l’ensemble (RCa 1,46, IC95 % 1,25-1,72) et par sous-types : OS seul (RCa 1,47, IC95% 1,04-2,07), TRA seul (RCa 1,76, IC95% 1,01-3,06) et SO/TRA combinés (RCa 1,43, IC95% 1,19-1,73) étaient associées à un risque accru de prématurité par rapport à la conception spontanée. Enfin, l’étude 3 quantifie le risque de naitre petit/très petit pour l'âge gestationnel associé à la PMA dans l’ensemble et par sous-types. Connaissant l'association PMA/prématurité, nous avons aussi évalué le rôle de la prématurité comme modificateur d'effet dans l'association entre PMA et le fait de naitre petit ou très petit pour l'âge gestationnel. Bien qu'aucune association n'ait été observée entre la PMA et le fait de naitre petit ou très petit pour l'âge gestationnel, la PMA était associée à un risque accru de naitre petit ou très petit pour l'âge gestationnel (RCa 1,69, IC95 % 1,08-2,66) chez les prématurés spécifiquement. Nos résultats démontrent une augmentation significative des grossesses multiples pendant le programme, au-delà des seuils visés. Les SO seuls augmentent particulièrement les grossesses multiples, une technique de PMA ne pouvant être contrôlée par le transfert d’embryon unique. La PMA augmente le risque de prématurité, en particulier chez les singletons. Nos résultats confirment en outre qu’elle augmente également le risque de naitre petit pour l’âge gestationnel, en particulier chez singletons prématurés. / Infertility affects 11-15% of Canadian women, while 8-20% of couples report having difficulties conceiving spontaneously. As such, the use of medically assisted reproduction (MAR) has steadily increased, however controversy remains with regards to its risks on the health of mothers and children. MAR includes assisted reproductive technology (ART) (i.e. in vitro fertilization [IVF], intrauterine insemination [IUI]) and ovarian stimulators (OS), with over 5 million children born through IVF alone worldwide. MARs have previously been associated with an increased risk of adverse pregnancy outcomes including gestational hypertension, uterine bleeding as well as adverse child health outcomes including multiplicity, prematurity, and low birth weight. Perinatal outcomes will be the focus in this doctoral thesis. Between 05/08/2010-15/11/2015, Quebec was the first Canadian province to fund a universal MAR reimbursement program, which aimed to reduce multiplicity and associated health expenditures with the practice of single embryo transfers in the context of IVF and increase Quebec’s birth rate. The program was halted in 2015 following a higher than expected healthcare expenditure. We identified several knowledge gaps, which we have aimed to fill through this doctoral program. First, no database exists to assess the impact of Quebec’s universal MAR program on mothers and children. Second, evidence focuses on ART or combine all non-IVF (e.g. OS) methods together, which has limited clinical implications. OS are under analysed but carry clinical implications as they are a first line therapy for infertility. Lastly, singleton pregnancies are not always evaluated when it has become evident that they carry clinically relevant perinatal risks. This doctoral thesis is composed of a published literature review as well as three epidemiological studies conducted within the Quebec Pregnancy Cohort (QPC). Study 1 aimed to quantify the changes in quarterly trends of obstetrical and perinatal outcomes 5 years before and during the universal program in Quebec through an interrupted time series analysis, as well as quantify the risk of multiplicity in association with the program itself and MAR conceptions specifically during the active program years. In this first study we also aimed to evaluate the role of multiplicity as an effect modifier in the association between MAR conception and prematurity. Between 2005-2015, we observed a 10-fold increase in multiplicity. Multiplicity increased by 6-fold during the program (adjusted odds ratio [aOR] 6.09, 95% confidence interval [CI] 5.23-7.09) compared to 5 years prior. MAR significantly increased the risk of multiplicity by 4.7-fold (aOR 4.65, 95%CI 3.84-5.62) compared to spontaneous conception. OS alone increased the risk of multiplicity the most (aOR 6.28, 95%CI 4.56-8.64) compared to spontaneous conception. In Study 2, we quantified the risk of prematurity associated with MAR conceptions overall and by subtype (eg. OS alone, ART alone, OS/ART combined) among singleton pregnancies occurring during the program as well as in a restricted cohort of MAR-exposed pregnancies to evaluate the impact of indication (infertility/subfertility) bias. MAR conception was associated with an increased prematurity risk (aOR 1.46, 95%CI 1.25-1.72). All MAR types were associated with increased prematurity risk when compared to spontaneous conception: OS alone (aOR 1.47, 95%CI 1.04-2.07), ART alone (aOR 1.76, 95%CI 1.01-3.06), and OS/ART combined (aOR 1.43, 95%CI 1.19-1.73). Lastly, in Study 3, we aimed to quantify the risk of being born small/very small for gestational age (SGA, VSGA) associated with MAR overall and by subtype. In this study, knowing the MAR/prematurity association, we assessed the role of prematurity as an effect modifier in the association between MAR and SGA/VSGA. While no association was observed between MAR and SGA/VSGA, MAR was associated with an increased SGA risk (aOR 1.69, 95%CI 1.08-2.66) among preterms. Our findings show a significant increase of multiplicity during the program years, well above the thresholds targeted by the program administrators. OS alone particularly increases multiplicity the most, an MAR technique that cannot be controlled through single embryo transfer. MARs increase the risk of preterm, particularly among singleton pregnancies. Our results further confirm that they also increase the risk of SGA, specifically among preterm singleton pregnancies.

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