Influence of gestational and perinatal factors on body composition of full-term newborns / Influência de fatores gestacionais e perinatais na composição corporal de recém-nascidos a termo

Abstract Objective: To evaluate the influence of gestational and perinatal factors on body composition and birth weight of full-term newborns. Method: This was a cross-sectional study, within a prospective cohort, consisting of 124 postpartum women and their newborns. Data included the following: maternal age; ethnicity; pre-gestational body mass index; gestational weight gain; parity; gestational morbidities (hypertension and gestational diabetes mellitus); gestational age at birth; birth weight; and newborn's gender. Anthropometric and body composition data of the newborns were collected using air-displacement plethysmography (PeaPod® Infant Body Composition System-LMI; Concord, CA, USA). The stepwise technique was applied to a multiple linear regression model. Results: The significant variables in the model that explained 84% of the variation in neonatal fat-free mass were: birth weight; maternal age; newborn's gender and gestational age. For body fat mass: birth weight; newborn's gender; gestational arterial hypertension; gestational diabetes; and gestational weight gain. These variables explained 60% and 46% of fat mass, in grams and as a percentage, respectively. Regarding birth weight, the significant factors were gestational age, pre-gestational BMI, and gestational weight gain. Female newborns showed higher body fat mass and male newborns had higher fat-free mass. Conclusion: Gestational and perinatal factors influence neonatal body composition. Early identification of these gestational factors, which may be modifiable, is necessary to prevent obesity and chronic noncommunicable diseases in the future.

Resumo Objetivo: Avaliar a influência de fatores gestacionais e perinatais na composição corporal e no peso de nascimento de recém-nascidos a termo. Método: Estudo transversal, dentro de uma coorte prospectiva, composto por 124 puérperas e seus recém-nascidos. Os dados incluíram: idade materna; etnia; índice de massa corpórea pré-gestacional; ganho de peso gestacional; paridade; morbidades gestacionais, (hipertensão arterial e diabetes mellitus gestacional); idade gestacional do nascimento; peso de nascimento; e sexo do recém-nascido. Os dados antropométricos e de composição corporal dos recém-nascidos foram coletados com a pletismografia por deslocamento de ar (PeaPod®). Foi aplicada a técnica de stepwise no modelo de regressão linear múltipla. Resultados: As variáveis significativas do modelo que explicou 84% da variação da massa livre de gordura neonatal foram: peso de nascimento; idade materna; sexo do recém-nascido; e idade gestacional. Para a massa de gordura corporal: peso de nascimento; sexo do recém-nascido; hipertensão arterial gestacional; diabetes gestacional; e ganho de peso gestacional. Essas variáveis explicaram 60% e 46% da massa de gordura, em gramas e percentual, respectivamente. Em relação ao peso de nascimento os fatores significativos foram: idade gestacional; IMC pré-gestacional; e ganho de peso gestacional. Os recém-nascidos do sexo feminino apresentaram maior massa de gordura corporal e os do sexo masculino maior massa livre de gordura. Conclusão: Fatores gestacionais e perinatais influenciam a composição corporal neonatal. A identificação precoce desses fatores gestacionais, que podem ser modificáveis, é necessária para prevenção de obesidade e de doenças crônicas não transmissíveis no futuro.

Gestational weight gain and body composition of full-term newborns and infants: a cohort study.

BACKGROUND: The association between gestational weight gain and neonatal body composition has been inconsistent, exposing the need for further research. The aim of this study was to evaluate whether gestational weight gain influences the body composition of full-term newborns and infants up to 4 months old. METHODS: A cohort study was performed with 124 participants divided into categories of gestational weight gain according to the 2009 Institute of Medicine guidelines. The anthropometric and body composition data of newborns and infants acquired using air displacement plethysmography (PeaPod®) were collected at 96 h, 1 month, 2 months and 4 months of life. In the statistical analysis, the chi-square test was used to analyze categorical variables, and ANOVA was used to analyze numerical variables. Univariate analysis was performed, and the absolute and relative frequencies of the categorical variables, as well as mean and standard deviation of the numerical variables, were obtained. Bivariate analysis was performed for the categories of gestational weight gain and gestational and neonatal characteristics. When adjustments to gestational hypertension, gestational diabetes, and pregestational body mass index (BMI) were analyzed by linear regression, gestational weight gain remained a significant variable for newborn percent fat mass. For all analyses, a significance level of 5% was adopted. RESULTS: Gestational weight gain was adequate in 33.8% of the participants, excessive in 41.1% and insufficient in 25%. Women with excessive weight gain had higher pregestational BMIs and a higher incidence of gestational hypertension. Their newborns had a higher body mass, body fat mass in grams and percent fat mass than the infants born to mothers with adequate or insufficient gestational weight gain. No significant differences were observed in body composition at 1, 2 and 4 months of life during infant follow-up. CONCLUSION: Excessive gestational weight gain may alter the body composition of newborns at birth. Further studies are required to better evaluate infant follow-up. TRIAL REGISTRATION: Clinical Trial Registry: NCT00875251 on April 3, 2009.

Influence of gestational and perinatal factors on body composition of full-term newborns.

OBJECTIVE: To evaluate the influence of gestational and perinatal factors on body composition and birth weight of full-term newborns. METHOD: This was a cross-sectional study, within a prospective cohort, consisting of 124 postpartum women and their newborns. Data included the following: maternal age; ethnicity; pre-gestational body mass index; gestational weight gain; parity; gestational morbidities (hypertension and gestational diabetes mellitus); gestational age at birth; birth weight; and newborn's gender. Anthropometric and body composition data of the newborns were collected using air-displacement plethysmography (PeaPod® Infant Body Composition System-LMI; Concord, CA, USA). The stepwise technique was applied to a multiple linear regression model. RESULTS: The significant variables in the model that explained 84% of the variation in neonatal fat-free mass were: birth weight; maternal age; newborn's gender and gestational age. For body fat mass: birth weight; newborn's gender; gestational arterial hypertension; gestational diabetes; and gestational weight gain. These variables explained 60% and 46% of fat mass, in grams and as a percentage, respectively. Regarding birth weight, the significant factors were gestational age, pre-gestational BMI, and gestational weight gain. Female newborns showed higher body fat mass and male newborns had higher fat-free mass. CONCLUSION: Gestational and perinatal factors influence neonatal body composition. Early identification of these gestational factors, which may be modifiable, is necessary to prevent obesity and chronic noncommunicable diseases in the future.

Freezing and thawing effects on fat, protein, and lactose levels of human natural milk administered by gavage and continuous infusion / Efeito do congelamento e descongelamento nos níveis de gordura, proteína e lactose do leite humano natural administrados por gavagem e infusão contínua

OBJECTIVES: to analyze the changes in human milk macronutrients: fat, protein, and lactose in natural human milk (raw), frozen and thawed, after administration simulation by gavage and continuous infusion. METHOD: an experimental study was performed with 34 human milk samples. The infrared spectrophotometry using the infrared analysis equipment MilkoScan Minor(r) (Foss, Denmark) equipment was used to analyze the macronutrients in human milk during the study phases. The analyses were performed in natural (raw) samples and after freezing and fast thawing following two steps: gavage and continuous infusion. The non-parametric Wilcoxon test for paired samples was used for the statistical analysis. RESULTS: the fat content was significantly reduced after administration by continuous infusion (p < 0.001) during administration of both raw and thawed samples. No changes in protein and lactose content were observed between the two forms of infusion. However, the thawing process significantly increased the levels of lactose and milk protein. CONCLUSION: the route of administration by continuous infusion showed the greatest influence on fat loss among all the processes required for human milk administration. .

OBJETIVO: analisar as alterações dos macronutrientes gordura, proteína e lactose no leite humano natural, congelado e descongelado, após a simulação da administração da dieta por gavagem e infusão contínua. MÉTODO: foi conduzido um estudo experimental com 34 amostras de leite humano. Foi utilizada a técnica da espectofotometria infravermelha (Milko Scan Minor(r)) para analisar os macronutrientes do leite humano nas etapas do estudo. As amostras foram analisadas na forma natural (crua) e após congelamento e descongelamento rápido nas duas formas de infusão: gavagem e infusão contínua. Foi usado o teste não paramétrico de Wilcoxon para amostras pareadas na análise estatística. RESULTADO: a gordura apresentou redução significativa após administração por infusão contínua (p < 0,001), tanto durante administração na forma natural quanto na forma descongelada. Não houve alteração da proteína e lactose segundo forma de infusão no leite descongelado e no leite in natura. O processo de descongelamento aumentou significativamente os níveis de lactose e de proteína do leite. CONCLUSÃO: a via de administração por infusão contínua foi o procedimento que mais influenciou na perda de gordura, dentre todos os processos necessários para administração do leite humano. .

Freezing and thawing effects on fat, protein, and lactose levels of human natural milk administered by gavage and continuous infusion.

OBJECTIVES: to analyze the changes in human milk macronutrients: fat, protein, and lactose in natural human milk (raw), frozen and thawed, after administration simulation by gavage and continuous infusion. METHOD: an experimental study was performed with 34 human milk samples. The infrared spectrophotometry using the infrared analysis equipment MilkoScan Minor® (Foss, Denmark) equipment was used to analyze the macronutrients in human milk during the study phases. The analyses were performed in natural (raw) samples and after freezing and fast thawing following two steps: gavage and continuous infusion. The non-parametric Wilcoxon test for paired samples was used for the statistical analysis. RESULTS: the fat content was significantly reduced after administration by continuous infusion (p<0.001) during administration of both raw and thawed samples. No changes in protein and lactose content were observed between the two forms of infusion. However, the thawing process significantly increased the levels of lactose and milk protein. CONCLUSION: the route of administration by continuous infusion showed the greatest influence on fat loss among all the processes required for human milk administration.

Indirect calorimetry: a tool to adjust energy expenditure in very low birth weight infants.

OBJECTIVE: To determine the resting metabolic rate in very low birth weight infants through indirect calorimetry. METHODS: Cross-sectional study including 29 clinically stable very low birth weight infants receiving an enteral diet > 100 kcal/kg/day. Malnutrition was defined as weight-for-age z score < or = - 2 SD. Resting energy expenditure was measured using open circuit indirect calorimetry. RESULTS: At the time of the examination, mean weight was 1,564+/-393 g and corrected gestational age was 35+/-3 weeks. Malnutrition was diagnosed in 62.1% of the preterm infants. The mean resting metabolic rate was 57.01+/-7.76 kcal/kg/day. CONCLUSION: Since resting energy expenditure is the main caloric component of total energy expenditure, the high resting metabolic rate observed may have a strong impact on the development of malnutrition during hospitalization.