Improving pregnancy outcome in obese women

AIMS AND OBJECTIVES. This programme evaluates the implementation of an individualised dietary and physical activity behavioural intervention to improve pregnancy outcome in obese women, thereby alleviating the burden of ill-health and reducing NHS costs.BACKGROUND. In the UK more than 20% of women of childbearing age are obese and the prevalence of obesity amongst pregnant women is spiralling, placing an unanticipated burden on health care resources. This programme application coincides with the Foresight obesity report (October 2007) [1] which indicates that early life intervention is the only potential policy response to the obesity epidemic which has a significant impact in all three scenario contexts explored. The programme also addresses the Health Inequalities Infant Mortality PSA target 2, identifying obesity amongst women in routine and manual occupations as a target for intervention. Obesity in pregnancy is a major cause of maternal mortality and increases the risk of maternal and neonatal morbidity. Insulin resistance plays a central role, leading to gestational diabetes, pre-eclampsia and excessive fetal growth. Large for gestational age infants are at risk of in utero death, and delivery is often complicated. Through development of pre-eclampsia obese women have increased risk of fetal growth restriction. The associated need for medical intervention and the greater duration of inpatient care leads to a substantial burden on healthcare resources. In non-pregnant obese subjects, Cognitive Behavioural Therapy (CBT) is effective in changing dietary and exercise behaviour. This programme will develop and evaluate a complex behavioural intervention to improve pregnancy outcome, focusing on physical activity, dietary advice and group support. This will be conducted in accordance with the MRC framework for development and evaluation of RCTs for complex interventions to improve health. RESEARCH PLANS. Phase 1 (0-8 months) involves development of the intervention and validation of the instruments to be used (diet and physical activity). We shall undertake rigorous qualitative assessments of acceptability of the proposed intervention for obese pregnant women. Phase 2 (9-22 months) involves a pilot trial to ascertain that the intervention changes dietary and physical activity behaviour, and to test all practical aspects of the study. Phase 3 (23-60 months) is the definitive RCT. The primary neonatal outcome (powered for) of the RCT is ‘Large for Gestational Age’ deliveries, and the primary maternal outcome (powered for) is impaired glucose tolerance, a robust index of maternal adverse endpoints. RESEARCH TEAM. A multidisciplinary team will develop and test the complex intervention. Applicants Poston, Shennan, Robson, Baker and McDonald bring expertise in obstetrics and RCTs. Briley is an experienced clinical trial manager in obstetrics. Wardle is an authority on CBT in obesity. Sandall works with the DoH in implementation of health care strategies in pregnancy. Sanders has extensive nutritional expertise. K Godfrey manages a large cohort study of nutrition and body composition in pregnancy (Southampton Womens’ Survey). Bell brings experience in Public Health Medicine. C Godfrey brings expertise in health economics.RESEARCH ENVIRONMENT. All centres have Clinical Research Facilities (CRF) for patient recruitment and study. The trial will be coordinated from the KCL/GSTT team which has studied >10,000 pregnant women in the past 10 years, The Unit is embedded in the KCL/Guys and St Thomas’ Trust NIHR Biomedical Research Centre (BRC). The GSTT/KCL CRF will open in March 2008 and this will be one of the first studies to use the facility. Infrastructural and management support has been provided for 5 years by NIHR BRC funds. ANTICIPATED OUTPUTS. The main output is a complex behavioural intervention of dietary advice, physical activity and individual support to improve pregnancy outcome in obese women, rapidly translatable to NHS prac