Fetal overgrowth is associated with adverse outcomes for offspring and with maternal obesity. Results from a systematic review and meta-analysis showed that maternal obesity is associated with fetal overgrowth, defined as birthweight ≥4000g (OR 2.17, 95% CI 1.92, 2.45), birthweight ≥4500g (OR 2.77, 95% CI 2.22, 3.45) and birthweight ≥90%ile for gestational age (OR 2.42, 95% CI 2.16, 2.72). A retrospective cohort study revealed that mothers whose infants are macrosomic are more likely to require induction of labour (OR 1.42, 95% CI 1.10-1.98) and delivery by Cesarean section (OR 1.45, 95% CI 1.04-2.01), particularly for maternal indications (OR 3.7, 95% CI 1.47-9.34), if they are obese. Infants from these pregnancies are significantly more likely to require neonatal resuscitation in the form of free flow oxygen (OR 1.57, 95% CI 1.03, 2.42) than macrosomic infants of non-obese mothers. Thus, co-existing maternal obesity and macrosomia increases the risk of adverse pregnancy outcomes.

High birth weight (also known as macrosomia) is a problem that has as of yet received little attention by health researchers, in particular, health economists. High birth weight is a concern mostly due to the increased difficulties it presents during birth for both the mother and the baby but there is also concern that high birth weight may continue to present negative effects later in the baby’s life. Many factors have been attributed as risk factors for high birth weight including mother’s age, ethnicity, parity, obesity, weight gain during pregnancy, infant gender, and gestation length. However, there is a dearth of careful analysis dedicated to determining the extent of causality of these risk factors where endogeneity concerns are present. In this thesis, I examine various issues surrounding high birth weight. I describe the situation in New Zealand (Chapter 2) to see if our experience with high birth weight reflects that found in international research. I analyse the relationship between socio-economic status and high birth weight (Chapter 3) to explore whether high socio-economic status has a unique effect on high birth weight compared to other health disorders in which it generally helps alleviate the incidence. I further investigate the relationship between obesity and high birth weight (Chapter 4) in an attempt to disentangle the causal effect of obesity on high birth weight risk from the mere correlation that has been well documented. I explore the possibility of vitamin and mineral supplements taken during pregnancy being a risk factor for high birth weight (Chapter 5), then address the potential endogeneity issues to identify a causal impact. Finally, I return to the definition of high birth weight (Chapter 6) and consider the optimal way to define the “problematic” weight threshold and whether this threshold should depend on gestation length or the ethnicity of the mother. My findings suggest that in New Zealand, the incidence of macrosomia varies by the ethnicity and weight group of the mother and the gender of the infant. Socio-economic status does seem to affect high birth weight risk but the nature of the relationship is complex. Obesity only appears to have a significant causal effect on high birth weight risk for women who are morbidly obese, but even for these women conventional estimation that disregards the endogeneity of obesity greatly exaggerates the effect. There does appear to be a correlation between iron supplementation and high birth weight risk but the relationship does not withstand controlling for endogeneity. My findings indicate that the currently accepted threshold used to define macrosomia is justified as it does consistently predict adverse health outcomes. However, flexible definitions which consider different grades of macrosomia or different thresholds for different ethnicities could improve on the current definition.

Fetal overgrowth is associated with adverse outcomes for offspring and with maternal obesity. Results from a systematic review and meta-analysis showed that maternal obesity is associated with fetal overgrowth, defined as birthweight ≥4000g (OR 2.17, 95% CI 1.92, 2.45), birthweight ≥4500g (OR 2.77, 95% CI 2.22, 3.45) and birthweight ≥90%ile for gestational age (OR 2.42, 95% CI 2.16, 2.72). A retrospective cohort study revealed that mothers whose infants are macrosomic are more likely to require induction of labour (OR 1.42, 95% CI 1.10-1.98) and delivery by Cesarean section (OR 1.45, 95% CI 1.04-2.01), particularly for maternal indications (OR 3.7, 95% CI 1.47-9.34), if they are obese. Infants from these pregnancies are significantly more likely to require neonatal resuscitation in the form of free flow oxygen (OR 1.57, 95% CI 1.03, 2.42) than macrosomic infants of non-obese mothers. Thus, co-existing maternal obesity and macrosomia increases the risk of adverse pregnancy outcomes.

Fetal overgrowth is associated with adverse outcomes for offspring and with maternal obesity. Results from a systematic review and meta-analysis showed that maternal obesity is associated with fetal overgrowth, defined as birthweight ≥4000g (OR 2.17, 95% CI 1.92, 2.45), birthweight ≥4500g (OR 2.77, 95% CI 2.22, 3.45) and birthweight ≥90%ile for gestational age (OR 2.42, 95% CI 2.16, 2.72). A retrospective cohort study revealed that mothers whose infants are macrosomic are more likely to require induction of labour (OR 1.42, 95% CI 1.10-1.98) and delivery by Cesarean section (OR 1.45, 95% CI 1.04-2.01), particularly for maternal indications (OR 3.7, 95% CI 1.47-9.34), if they are obese. Infants from these pregnancies are significantly more likely to require neonatal resuscitation in the form of free flow oxygen (OR 1.57, 95% CI 1.03, 2.42) than macrosomic infants of non-obese mothers. Thus, co-existing maternal obesity and macrosomia increases the risk of adverse pregnancy outcomes.

Background and Objectives: To date, no research has examined the prevalence and management of suspected fetal macrosomia in midwifery care, which may provide an alternative approach to cesarean section and induction with improvements in maternal and infant outcomes. The objectives of this study were to 1) determine the prevalence of fetal macrosomia and adverse outcomes that may result from a macrosomic birth in the MANAstats database; 2) identify the maternal characteristics which predict macrosomia; 3) determine the adverse maternal and infant outcome differences among macrosomic and normal weight infants in the MANAstats database. Methods: We analyzed 10,011 midwifery reported pregnancy and birth records from midwives across North America from January 2007- December 2009. After excluding for certain high-risk criteria, we compared the prevalence and adverse outcomes associated with macrosomic infants (4000-4499 grams, 4500-4999 grams, and >5000 grams) to non-macrosomic infants who weighed 3000-3000 grams. Results: The prevalence of macrosomia according to >4000 grams criteria was 24.7% and >4500 grams 5.53%. Maternal risk factors for macrosomia included: Caucasian race, married, maternal age between 15-34 years, and a gestational length greater than 40 weeks. The proportion of obstetric and infant complications showed a progressive and significant increase among the macrosomic birth weight categories with the highest risk at >5000 grams. The risk of shoulder dystocia (4000-4449-g infants: odds ratio, 4.08 [95% CI, 3.27-5.09]; 4500-4999-g infants: odds ratio, 8.31 [95% CI, 6.20-11.14]; and >5000-g infants: odds ratio, 29.92 [95% CI, 17.42-51.39]) and 5-minute Apgar scores 5000-g infants: odds ratio, 10.23 [95% CI, 2.32-45.13]) posed the highest risk in comparison to previous research on this topic. The prevalence of cesarean section among all groups was less than 9% and not found to be statistically significant by birthweight group. Conclusion: It is unclear if the risks shoulder dystocia and 5-minute Apgar scores < 3 outweigh the risks of prophylactic cesarean section on perceived macrosomic infants without jeopardizing maternal and infant health. Until further research regarding the risk versus benefit of alternatives to macrosomic vaginal birth, we recommend that strategies to prevent Grades II and III macrosomia need to be incorporated into the midwifery model of care. / Epidemiology

No description available.

El recién nacido (RN) hijo de madre diabética (HMD) tiene una morbimortalidad superior a los neonatos normales. Dos de las complicaciones más frecuentes son la hipoglucemia precoz (22,4%) y la macrosomía (29,4%). Por este motivo, los objetivos de esta Tesis Doctoral han sido: conocer el funcionalismo pancreático endocrino en estos niños, establecer criterios objetivos para la predicción de la hipoglucemia y la macrosomía, y detectar el hiperinsulinismo para su posterior seguimiento. La muestra ha consistido en 100 RN a término y sin sufrimiento fetal, distribuidos en un grupo control (15), el grupo de HMD (37 HMD tipo A de White y 28 HMD tipos B,C y D de White) y macrosomas no HMD (20). Los HMD se han analizado también bajo el prisma del control metabólico materno valorado mediante la hemoglobina glucosilada (HbA 1) estableciendo el límite de normalidad en el 8,2%. El diseño experimental durante la primera hora de vida estriba en monitorizar el descenso glucémico espontáneo, determinando la glucemia capilar cada 15' y a su vez, en cordón y a los 60' en sangre venosa la insulinemia (IRI), el C-péptido (CPR) y el glucagón (IRG) por radioinmunoensayo (RIA), así como la glucemia por polarografía. Las mismas mediciones se realizaron en la madre 5' previos al expulsivo, determinando además la HbA 1 por cromatografía de intercambio iónico y la tasa de anticuerpos anti insulina. Al 2°, 4° y 7° días de vida, se ha practicado una prueba de sobrecarga oral de glucosa a 1,5 g/kg midiendo la glucemia capilar cada 15' y con determinación previa y ulterior de las mismas hormonas.Otros datos recogidos han sido extraídos de las historias clínicas u obtenidos por somatometría. El análisis estadístico se ha informatizado utilizando el paquete de programas SPSSR.La relación entre la glucemia materna y la fetal ha mostrado un mejor ajuste a una cinética «michaeliana» en todos los grupos neonatales a excepción de los macrosomas no HMD, lo cual apoya la participación en el proceso de difusión facilitada de un transportador saturable que ejercería un efecto de protección fetal frente a la hiperglucemia materna extrema. En los macrosomas no HMD, al tener la placenta mayor superficie, pueden existir un mayor número de receptores no habiéndose alcanzado dicha saturación.El descenso glucémico, que sigue una cinética de primer orden, ha sido más intenso en los HMD con mal control metabólico a lo largo de la gestación. Utilizando la regresión múltiple se ha podido comprobar que el factor de mayor importancia ha consistido en una insensibilidad de la célula A de los islotes de Langerhans ante la hipoglucemia, y en segundo lugar el hiperinsulinismo presente ya al nacer, a pesar de la existencia de una reducción significativa del mismo. Bajo un punto de vista clínico, este descenso puede predecirse de forma significativa mediante la glucemia en cordón o la materna, la edad gestacional, la paridad y la HbA 1 promedio del tercer trimestre del embarazo.La somatometría de los HMD ha mostrado en todo momento unos valores superiores a los RN normales, a excepción de la longitud y del perímetro craneal. Esta diferencia puede ser parcialmente explicable por un aumento del tejido adiposo subcutáneo como efecto final del hiperinsulinismo. La relación placenta/fetal también está significativamente aumentada en e! HMD con respecto a los RN normales, lo cual puede potenciar la ya elevada oferta de nutrientes en estos niños y facilitar aun más la macrosomía. No se han evidenciado diferencias somatométricas ni metabólicas entre los macrosomas HMD y aquellos en cuya madre no se evidenció diabetes mellitas a lo largo del embarazo. Se ha podido constatar la relación del hiperinsulinismo y el control metabólico materno sobre el peso o el pliegue adiposo subcutáneo en los HMD; sin embargo esto no ha sido posible en los otros grupos neonatales. La predicción del peso neonatal no ha sido satisfactoria, debido probablemente al hecho de tratarse de un fenómeno polifactorial. Sí se ha podido predecir con un 87% de eficacia el estado macrosómico en los hijos de aquellas embarazadas consideradas normales durante la gestación mediante análisis del discriminante. Los datos más útiles han sido la superficie corporal materna, la paridad, el antecedente de macrosomía y la edad gestacional. La edad materna o el incremento de peso en la gestación actual no han mostrado participación.En el estudio evolutivo se ha comprobado una evolución ascendente de las glucemias basales influyendo la alimentación de forma que los niños con lactancia artificial presentaban valores superiores. Al estudiar la secreción de la célula B del páncreas se ha manifestado un auténtico hiperinsulinismo en el grupo de HMD con mal control metabólico, especialmente intenso al 2º día y tendiendo a una convergencia hacia el 7º día. La lactancia artificial y la administración del suero glucosado potencian dicho hiperinsulinismo. La ausencia de diferencias en las glucemias se explica por la administración exógena de glucosa y por unas mayores tasas de glucagón. Con respecto al área de la sobrecarga glucídica, este mismo grupo se ha significado sobre los demás, al presentar unas cifras más altas y una evolución ascendente a diferencia del resto de recién nacidos. Nuevamente en este grupo, se aprecia que la elevación del glucagón tras la sobrecarga es más intensa que en el resto, lo cual contribuiría a explicar este fenómeno.El balance metabólico global medido por la ratio IRI/IRG es francamente anabólico en los HMO respecto a los RN normales, tanto en la 1ª hora de vida como en la evolución posterior. Este fenómeno es especialmente manifiesto en los HMO con mal control, los cuales presentan una pérdida porcentual de peso inferior a los demás, coincidiendo pues con dicha interpretación.Un hallazgo original ha sido la elevada ratio molar IRI/CPR en los HMO y macrosomas no HMO respecto a los RN normales. En situaciones más estables como la determinación en sangre de cordón (que equivale al estado intraparto), así como las basales del estudio evolutivo, es cuando las diferencias se han hecho ostensibles. Al producirse distorsiones en el sistema biológico, bien por descenso glucémico y freno de la célula B, bien por estímulo de la misma tras la sobrecarga, dichas diferencias han desaparecido adoptando valores dentro del rango de normalidad. Esta anomalía sugiere la secreción en «reposo» de sustancias con reacción cruzada con el RIA de insulina. Un candidato a considerar es la proinsulina. / "GLUCOSE REGULATION AND ENDOCRINE PANCREAS IN THE NORMAL NEWBORN AND INFANT OF DIABETIC MOTHER. A FUNCTIONAL AND EVOLUTIVE STUDY". TEXT: Hundred newborns have been studied during spontaneous glucose decrease in the first hour of life and after oral glucose overload (1. 5 g/kg) in the 2nd, 4th and 7th days of life. Fifteen were normal babies, 65 infants of diabetic mothers (IDM) and 20 macrosomes non IDM. Glycosylated hemoglobin (HbA 1) was recorded as a control parameter with an upper limit at 8.2%. According that, the IDMs were divided in good and bad maternal control. Glucose, insulin, C-peptide and glucagon were measured in each situation. The best fit between maternal and fetal glucose was obtained with a saturable-kinetics 'model pointing to the role of a carrier in the placental transport of glucose. The glycemic decrease was greater in IDM bad controlled. The most important factor was the lack of a cell response in front of hypoglycemia and the hyperinsulinemia at cord, in spite of a significative reduction. Hypoglycemia could be predicted in IDM with maternal of cord glycemia, gestational age, parity and averaged HbA 1 at 3rd quarter of pregnancy. IDM are heavier than controls at expenses of subcutaneous fat. Insulin and maternal control are related with it. The ratio between placental and fetal weight was greater in IDM providing a positive feed-back with macrosomia. LGA state can be predicted with an accuracy of 87% in the normal pregnant using discriminant analysis. Maternal body surface, parity, LGA infant antecedent and gestational age are related in that prediction. Evolution along the first week of life demonstrated an increase in glucose basal values in all 7 groups. MANOVA analysis pointed out the different behaviour of IDM bad controlled. These babies showed higher C-peptide values and a greater area after glucose overload. This insulin-resistance could be explained by exogenous glucose administration and greater glucagon values in both, basal and afterload situations. A difference has been found with insulin/C-peptide ratio between normal group and all the others. A spurious secretion of proinsulin could be responsible due its cross-reaction with the radioimmunoassay of insulin.

Macrossomia fetal significa feto grande ou com sobrepeso, mais recentemente chamado de recém-nascido grande para idade gestacional. Diversos fatores afetam a distribuição do peso corporal fetal tais como a idade gestacional, tamanho materno, hereditariedade, estado socioeconômico, origem étnica entre tantos outros. Conseqüentemente, observa-se uma morbidade aumentada nesta situação. A tendência temporal da macrossomia foi avaliada em estudos realizados em outros países e mostrou aumento gradativo de sua prevalência, além de uma distribuição geográfica heterogênea. Objetivos: Avaliar a tendência temporal da macrossomia fetal em todo território brasileiro considerando fatores determinantes reconhecidamente responsáveis por interferirem no peso dos recém-nascidos. Mapear e identificar conglomerados de macrossomia fetal no território brasileiro e fatores espacialmente correlacionados.Para investigação da tendência temporal foram realizados levantamentos descritivos sobre 14.509.859 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) de 26 Unidades da Federação mais o Distrito Federal. As estatísticas descritivas foram apresentas sob a forma de tabelas para freqüências absolutas e relativas, médias aritméticas e descrições geométricas através de gráficos. Dados de 2.858.627 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) do ano de 2004 foram usados para realizar a parte da pesquisa sobre análise geográfica. A estatística espacial foi a metodologia utilizada para testar a presença de conglomerados e identificar sua localização aproximada. A contextualização geográfica espacial foi feita com o modelo Conditional Auto Regressive (CAR) sobre o mapa do Brasil desagregado em microrregiões. A prevalência geral da macrossomia entre 2000 e 2004 foi de 5,4%, iniciando com 6,0 % no ano 2000 e terminando com 5,1 % em 2004. A tendênciatemporal do percentual de macrossomia diminuiu ao longo dos anos, entretanto, o percentual de cesariana mostrou crescimento gradativo entre os estratos de peso de recém-nascidos. As demais variáveis estudadas foram percentuais de pós-termo, mãe adolescente, grau de instrução inferior, situação conjugal, cor da pele e consulta de prénatal infreqüente que mostraram redução gradativa a cada ano entre os estratos de peso dos recém-nascidos. Análises espaciais de 558 microrregiões brasileiras com os dados do SINASC de 2004 mostraram que o índice global de Moran do percentual de macrossomia fetal foi de 0,40. Foram identificados conglomerados de microrregiões com altos percentuais de macrossomia relacionadas com vizinhos de altos percentuais nas regiões norte-nordeste do país, entretanto os conglomerados de baixos percentuais foram encontrados nas regiões sul-sudeste. O modelo final da regressão comprovou a presença de dependência espacial do percentual de macrossomia com as variáveis percentuais de cesariana e grau de instrução inferior mantidas no modelo. A estratégia de especificação clássica foi usada para seleção do modelo final, indicando o modelo de erro espacial para verificação da autocorrelação espacial nos termos de erros. Conclusão: A tendência temporal da macrossomia no Brasil está em declínio, acompanhando tendências favoráveis em vários indicadores de saúde materno-infantil. No entanto, houve aumento de 10% no percentual de cesariana e de 6% no percentual de microssomia no período estudado. Conglomerados geográficos de macrossomia com dependência espacial foram caracterizados nas microrregiões brasileiras com percentuais de cesarianas e grau de instrução inferior contribuindo de forma significativa para este relacionamento espacial. / Fetal macrosomia means large or overweight fetus, more recently called large for gestational age. The birth weight is affected by many conditions such as gestational age, maternal size, hereditary factors, socioeconomic status, and ethnicity among others. Consequently, an increased morbidity is observed in this situation. The macrosomia temporal trend was investigated in studies conducted in other countries and showed gradual increased prevalence with a heterogeneous geographic distribution. Objectives: To evaluate the temporal trends of fetal macrosomia in the Brazilian territory considering the well known determinants that affect birth weight. To map and identify clusters of macrosomia in the Brazilian territory and its spatial correlation factors. Methods: Descriptive data of 14.509.859 birth registries were collected in the Brazilian Live Births Information System from 26 states and the Federal District. Statistics were shown in tables for absolute and relative frequencies, arithmetic means and graphics for geometric descriptions. Data of 2.858.627 birth registries from 2004 were used for the geographic analysis. Spatial statistics methodology was used to identify the clusters and their approximate location. The geographic contextualization was performed with Conditional Auto Regressive (CAR) model over disaggregated map of Brazilian microregions. Macrosomia overall prevalence was 5.4% starting with 6.0% in 2000 and finishing with 5.1% in 2004. The temporal trends of macrossomia percentage decreased during the study period, however, the cesarean percentage increased gradually over the birth weight stratus. The reminded studied variables, post-term delivery percentage, adolescent pregnancy, less than a full elementary education, married status, skim color and infrequent pre-natal care visits shown annual reduction over the birth weightstratus. SINASC 2004 spatial analysis of 558 Brazilian micro regions displayed macrosomia Moran’s I percentage of 0.40. Clusters of high percentage macrosomia micro-regions related to high percentage neighbors were identified in the northnortheast regions of the country, although clusters with low percentage were located in the south-southeast regions. The final regression model showed spatial dependence of macrosomia percentage maintaining cesarean and education variables in the model. The spatial error model was indicated to test the spatial autocorrelation in the terms of error in the final model using the classical specification strategy.The Brazilian macrosomia temporal trend is decreasing accompanied by favorable tendencies in nearly all maternal-infant health indicators, but an increase of 10% in the cesarean percentage and of 6% in microsomia was observed during the study period. Geographic macrosomia clusters with spatial dependence were characterized in the Brazilian micro regions with percentages of cesarean and less than a full elementary education significantly affecting this spatial relationship.

Macrossomia fetal significa feto grande ou com sobrepeso, mais recentemente chamado de recém-nascido grande para idade gestacional. Diversos fatores afetam a distribuição do peso corporal fetal tais como a idade gestacional, tamanho materno, hereditariedade, estado socioeconômico, origem étnica entre tantos outros. Conseqüentemente, observa-se uma morbidade aumentada nesta situação. A tendência temporal da macrossomia foi avaliada em estudos realizados em outros países e mostrou aumento gradativo de sua prevalência, além de uma distribuição geográfica heterogênea. Objetivos: Avaliar a tendência temporal da macrossomia fetal em todo território brasileiro considerando fatores determinantes reconhecidamente responsáveis por interferirem no peso dos recém-nascidos. Mapear e identificar conglomerados de macrossomia fetal no território brasileiro e fatores espacialmente correlacionados.Para investigação da tendência temporal foram realizados levantamentos descritivos sobre 14.509.859 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) de 26 Unidades da Federação mais o Distrito Federal. As estatísticas descritivas foram apresentas sob a forma de tabelas para freqüências absolutas e relativas, médias aritméticas e descrições geométricas através de gráficos. Dados de 2.858.627 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) do ano de 2004 foram usados para realizar a parte da pesquisa sobre análise geográfica. A estatística espacial foi a metodologia utilizada para testar a presença de conglomerados e identificar sua localização aproximada. A contextualização geográfica espacial foi feita com o modelo Conditional Auto Regressive (CAR) sobre o mapa do Brasil desagregado em microrregiões. A prevalência geral da macrossomia entre 2000 e 2004 foi de 5,4%, iniciando com 6,0 % no ano 2000 e terminando com 5,1 % em 2004. A tendênciatemporal do percentual de macrossomia diminuiu ao longo dos anos, entretanto, o percentual de cesariana mostrou crescimento gradativo entre os estratos de peso de recém-nascidos. As demais variáveis estudadas foram percentuais de pós-termo, mãe adolescente, grau de instrução inferior, situação conjugal, cor da pele e consulta de prénatal infreqüente que mostraram redução gradativa a cada ano entre os estratos de peso dos recém-nascidos. Análises espaciais de 558 microrregiões brasileiras com os dados do SINASC de 2004 mostraram que o índice global de Moran do percentual de macrossomia fetal foi de 0,40. Foram identificados conglomerados de microrregiões com altos percentuais de macrossomia relacionadas com vizinhos de altos percentuais nas regiões norte-nordeste do país, entretanto os conglomerados de baixos percentuais foram encontrados nas regiões sul-sudeste. O modelo final da regressão comprovou a presença de dependência espacial do percentual de macrossomia com as variáveis percentuais de cesariana e grau de instrução inferior mantidas no modelo. A estratégia de especificação clássica foi usada para seleção do modelo final, indicando o modelo de erro espacial para verificação da autocorrelação espacial nos termos de erros. Conclusão: A tendência temporal da macrossomia no Brasil está em declínio, acompanhando tendências favoráveis em vários indicadores de saúde materno-infantil. No entanto, houve aumento de 10% no percentual de cesariana e de 6% no percentual de microssomia no período estudado. Conglomerados geográficos de macrossomia com dependência espacial foram caracterizados nas microrregiões brasileiras com percentuais de cesarianas e grau de instrução inferior contribuindo de forma significativa para este relacionamento espacial. / Fetal macrosomia means large or overweight fetus, more recently called large for gestational age. The birth weight is affected by many conditions such as gestational age, maternal size, hereditary factors, socioeconomic status, and ethnicity among others. Consequently, an increased morbidity is observed in this situation. The macrosomia temporal trend was investigated in studies conducted in other countries and showed gradual increased prevalence with a heterogeneous geographic distribution. Objectives: To evaluate the temporal trends of fetal macrosomia in the Brazilian territory considering the well known determinants that affect birth weight. To map and identify clusters of macrosomia in the Brazilian territory and its spatial correlation factors. Methods: Descriptive data of 14.509.859 birth registries were collected in the Brazilian Live Births Information System from 26 states and the Federal District. Statistics were shown in tables for absolute and relative frequencies, arithmetic means and graphics for geometric descriptions. Data of 2.858.627 birth registries from 2004 were used for the geographic analysis. Spatial statistics methodology was used to identify the clusters and their approximate location. The geographic contextualization was performed with Conditional Auto Regressive (CAR) model over disaggregated map of Brazilian microregions. Macrosomia overall prevalence was 5.4% starting with 6.0% in 2000 and finishing with 5.1% in 2004. The temporal trends of macrossomia percentage decreased during the study period, however, the cesarean percentage increased gradually over the birth weight stratus. The reminded studied variables, post-term delivery percentage, adolescent pregnancy, less than a full elementary education, married status, skim color and infrequent pre-natal care visits shown annual reduction over the birth weightstratus. SINASC 2004 spatial analysis of 558 Brazilian micro regions displayed macrosomia Moran’s I percentage of 0.40. Clusters of high percentage macrosomia micro-regions related to high percentage neighbors were identified in the northnortheast regions of the country, although clusters with low percentage were located in the south-southeast regions. The final regression model showed spatial dependence of macrosomia percentage maintaining cesarean and education variables in the model. The spatial error model was indicated to test the spatial autocorrelation in the terms of error in the final model using the classical specification strategy.The Brazilian macrosomia temporal trend is decreasing accompanied by favorable tendencies in nearly all maternal-infant health indicators, but an increase of 10% in the cesarean percentage and of 6% in microsomia was observed during the study period. Geographic macrosomia clusters with spatial dependence were characterized in the Brazilian micro regions with percentages of cesarean and less than a full elementary education significantly affecting this spatial relationship.

Macrossomia fetal significa feto grande ou com sobrepeso, mais recentemente chamado de recém-nascido grande para idade gestacional. Diversos fatores afetam a distribuição do peso corporal fetal tais como a idade gestacional, tamanho materno, hereditariedade, estado socioeconômico, origem étnica entre tantos outros. Conseqüentemente, observa-se uma morbidade aumentada nesta situação. A tendência temporal da macrossomia foi avaliada em estudos realizados em outros países e mostrou aumento gradativo de sua prevalência, além de uma distribuição geográfica heterogênea. Objetivos: Avaliar a tendência temporal da macrossomia fetal em todo território brasileiro considerando fatores determinantes reconhecidamente responsáveis por interferirem no peso dos recém-nascidos. Mapear e identificar conglomerados de macrossomia fetal no território brasileiro e fatores espacialmente correlacionados.Para investigação da tendência temporal foram realizados levantamentos descritivos sobre 14.509.859 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) de 26 Unidades da Federação mais o Distrito Federal. As estatísticas descritivas foram apresentas sob a forma de tabelas para freqüências absolutas e relativas, médias aritméticas e descrições geométricas através de gráficos. Dados de 2.858.627 declarações de nascidos vivos do Sistema Informação sobre Nascidos Vivos (SINASC) do ano de 2004 foram usados para realizar a parte da pesquisa sobre análise geográfica. A estatística espacial foi a metodologia utilizada para testar a presença de conglomerados e identificar sua localização aproximada. A contextualização geográfica espacial foi feita com o modelo Conditional Auto Regressive (CAR) sobre o mapa do Brasil desagregado em microrregiões. A prevalência geral da macrossomia entre 2000 e 2004 foi de 5,4%, iniciando com 6,0 % no ano 2000 e terminando com 5,1 % em 2004. A tendênciatemporal do percentual de macrossomia diminuiu ao longo dos anos, entretanto, o percentual de cesariana mostrou crescimento gradativo entre os estratos de peso de recém-nascidos. As demais variáveis estudadas foram percentuais de pós-termo, mãe adolescente, grau de instrução inferior, situação conjugal, cor da pele e consulta de prénatal infreqüente que mostraram redução gradativa a cada ano entre os estratos de peso dos recém-nascidos. Análises espaciais de 558 microrregiões brasileiras com os dados do SINASC de 2004 mostraram que o índice global de Moran do percentual de macrossomia fetal foi de 0,40. Foram identificados conglomerados de microrregiões com altos percentuais de macrossomia relacionadas com vizinhos de altos percentuais nas regiões norte-nordeste do país, entretanto os conglomerados de baixos percentuais foram encontrados nas regiões sul-sudeste. O modelo final da regressão comprovou a presença de dependência espacial do percentual de macrossomia com as variáveis percentuais de cesariana e grau de instrução inferior mantidas no modelo. A estratégia de especificação clássica foi usada para seleção do modelo final, indicando o modelo de erro espacial para verificação da autocorrelação espacial nos termos de erros. Conclusão: A tendência temporal da macrossomia no Brasil está em declínio, acompanhando tendências favoráveis em vários indicadores de saúde materno-infantil. No entanto, houve aumento de 10% no percentual de cesariana e de 6% no percentual de microssomia no período estudado. Conglomerados geográficos de macrossomia com dependência espacial foram caracterizados nas microrregiões brasileiras com percentuais de cesarianas e grau de instrução inferior contribuindo de forma significativa para este relacionamento espacial. / Fetal macrosomia means large or overweight fetus, more recently called large for gestational age. The birth weight is affected by many conditions such as gestational age, maternal size, hereditary factors, socioeconomic status, and ethnicity among others. Consequently, an increased morbidity is observed in this situation. The macrosomia temporal trend was investigated in studies conducted in other countries and showed gradual increased prevalence with a heterogeneous geographic distribution. Objectives: To evaluate the temporal trends of fetal macrosomia in the Brazilian territory considering the well known determinants that affect birth weight. To map and identify clusters of macrosomia in the Brazilian territory and its spatial correlation factors. Methods: Descriptive data of 14.509.859 birth registries were collected in the Brazilian Live Births Information System from 26 states and the Federal District. Statistics were shown in tables for absolute and relative frequencies, arithmetic means and graphics for geometric descriptions. Data of 2.858.627 birth registries from 2004 were used for the geographic analysis. Spatial statistics methodology was used to identify the clusters and their approximate location. The geographic contextualization was performed with Conditional Auto Regressive (CAR) model over disaggregated map of Brazilian microregions. Macrosomia overall prevalence was 5.4% starting with 6.0% in 2000 and finishing with 5.1% in 2004. The temporal trends of macrossomia percentage decreased during the study period, however, the cesarean percentage increased gradually over the birth weight stratus. The reminded studied variables, post-term delivery percentage, adolescent pregnancy, less than a full elementary education, married status, skim color and infrequent pre-natal care visits shown annual reduction over the birth weightstratus. SINASC 2004 spatial analysis of 558 Brazilian micro regions displayed macrosomia Moran’s I percentage of 0.40. Clusters of high percentage macrosomia micro-regions related to high percentage neighbors were identified in the northnortheast regions of the country, although clusters with low percentage were located in the south-southeast regions. The final regression model showed spatial dependence of macrosomia percentage maintaining cesarean and education variables in the model. The spatial error model was indicated to test the spatial autocorrelation in the terms of error in the final model using the classical specification strategy.The Brazilian macrosomia temporal trend is decreasing accompanied by favorable tendencies in nearly all maternal-infant health indicators, but an increase of 10% in the cesarean percentage and of 6% in microsomia was observed during the study period. Geographic macrosomia clusters with spatial dependence were characterized in the Brazilian micro regions with percentages of cesarean and less than a full elementary education significantly affecting this spatial relationship.