Gestational Weight Gain : Implications of an Antenatal Lifestyle Intervention

Background: Excessive gestational weight gain (GWG) is common in developed countries and is associated with an increased risk of maternal and offspring morbidity. Evidence regarding efficacy and safety of antenatal lifestyle intervention is limited in terms of both systematic reviews and original trials. This thesis is based on the need to further explore this research area. Objectives: To assess and grade current evidence and evaluate short and long-term effects of an antenatal lifestyle intervention on women and their offspring Materials: Controlled trials of intervention publishedbefore August 2009 were systematically searched and reviewed. A randomized controlled trial (RCT) including 445 healthy women aged >18 years with a body mass index (BMI) ≥19 and ≤16 weeks pregnant and their offspring was performed during 2007-2015 in Örebro Region, Sweden. Methods: The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was used for review. Our RCT (called the VIGA trial) compared standard care with a composite intervention consisting of education, application of a personalized weight graph, prescription of exercise and more frequent monitoring of weight. Standardized measures of weight and height in offspring waere analysed based on World Health Organization (WHO) Child Growth Standards. Results: Quality of evidence across the studies published pre-August 2009 was concluded to be very low. Our intervention significantly reduced mean GWG (kg) but the proportion of women with excessive GWG, according to recommendations, was not significantly reduced. Short- term postpartum weight retention (PPWR) was significantly lower after the intervention but no significant difference remained 1 year after delivery. Offspring mean BMI z-scores or proportion of obesity did not differ between study groups at either birth or age 5. Conclusions: The antenatal lifestyle intervention reduced mean GWG and short-term PPWR but no long-term effects on maternal weight retention or offspring obesity were seen. Alternative modes and timing of intervention should be considered in future research. Reducing the prevalence of pre-conception obesity must still be considered the primary means to improve maternal and fetal outcome