Physical activity during pregnancy and fetal outcomes: a case-control study

Abstract

OBJECTIVE:To investigate the relationship between physical activity during the second trimester pregnancy and low birth weight, preterm birth, and intrauterine growth restriction. METHODS:Case-control study including 273 low birth weight newborns and 546 controls carried out in the city of São Paulo, Southeastern Brazil, in 2005. Low birth weight cases were grouped into two subsamples: preterm birth (n=117) and intrauterine growth restriction (n=134), with their related controls. Information was collected by means of interviews with mothers shortly after birth and transcription of medical records. Data were analyzed using conditional multiple and hierarchical logistic regression. RESULTS:Light physical activity for over 7 hours per day was shown to be protective against low birth weight (adjusted OR=0.61; 95% CI 0.39-0.94) with a dose-response relationship (p-value for trend=0.026). A similar trend was found for intrauterine growth restriction (adjusted OR=0.51; 95% CI 0.26-0.97). Homemaking activities were associated as a protective factor for both low birth weight and preterm birth (p-value for trend=0.013 and 0.035, respectively). Leisure-time walking was found to be protective against preterm birth. CONCLUSIONS:Mild physical activity during the second trimester of pregnancy such as walking has an independent protective effect on low birth weight, preterm birth, and intrauterine growth restriction. Low birth weight is an important public health issue in both developed and developing countries. It is the main factor infl uencing health and nutritional conditions and child survival, and is also associated with occurrence of chronic diseases in adult life. 10Over the past two decades -in contrast to the declining trend seen for many health indicators, such as child mortality, postnatal malnutrition, and malnutrition among adult women -prevalence of low birth weight (under 2,500 grams) has remained stable, or even increased in cities of Southern and Southeastern Brazil. There are two major processes that can lead to low birth weight: preterm birth and restricted intrauterine growth. In the city of Pelotas, over the last two decades, Barros et al 2 observed a slight increase in the prevalence of low birth weight and a greater increase in preterm birth (6.3% in 1982 to 16.2% in 2004), whereas prevalence of intrauterine growth restriction (IUGR) remained unaltered. RESUMO OBJETIVO:Analisar a relação entre atividade física durante o segundo trimestre de gestação e baixo peso ao nascer, prematuridade e restrição de crescimento intra-uterino. MÉTODOS:Estudo de caso-controle realizado no município de São Paulo, em 2005. Foram estudados 273 recém-nascidos de baixo peso e 546 controles. Dentre os casos foram selecionadas duas sub-amostras: 117 nascimentos pré-termo e 132 com restrição de crescimento intra-uterino (n=132) e seus respectivos controles. As informações foram obtidas mediante entrevistas com as puérperas e transcrição de dados dos prontuários. Foram realizadas análises de regressão logística múltipla...

Non-occupational physical activity during pregnancy and the risk of preterm birth: a meta-analysis of observational and interventional studies

“…Therefore, 37 eligible studies (7 case control studies, 18 cohort studies, and 12 interventional studies) were included in the meta-analysis. All the included 25 observational studies (7 case-control studies and 18 cohort studies) were rated as either high18 or moderate91920212223242526272829303132333435363738394041 quality (see Supplemental Tables S1 and S2). …”

“…Of them, 9 studies were conducted in North America92021262734353641, 3 in Europe293033, 3 in the Asia-Pacific region253739, and 2 in South America2832. Data on domestic PA and the risk of PTB were presented by 7 cohort studies9222324253134 (11,009 participants and 747 cases), and 3 case-control studies182140 (391 cases and 651 controls). Of these studies, 3 were conducted in North America92134, 2 in Europe2223, 2 in the Asia-Pacific region2425, 2 in Africa1831, and 1 in South America40.…”

Mental health and physical inactivity during pregnancy: a cross-sectional study nested in the BRISA cohort study

“…The rate of physical inactivity during pregnancy is high, ranging from 64.5% to 91.5% 6,7,8,9,10,11 , and tends to be lower in the third trimester of pregnancy 12,13 . In addition, physical inactivity during pregnancy is associated with an increased probability of admission of infants to neonatal intensive care units, preterm delivery 14 , low birth weight, intrauterine growth restriction 15 , cesarean sections and stillbirths 11 .…”

Physical activity in pregnancy and adverse birth outcomes

“…Interrelations between variables were constructed based on Takito & Benicio's theoretical hierarchical model 22 . Models were then adjusted for maternal schooling, economic class, living with partner, and living with children.…”