This HTA project will systematically review the evidence of effectiveness and potential adverse effects of various dietary interventions on pregnant women (normal weight and obese or overweight women) and their offspring collating This health technology assessment (HTA) project was undertaken to evaluate the evidence on dietary and lifestyle interventions to reduce weight or prevent weight gain in pregnancy. The objectives were to: •determine the effectiveness of various dietary and lifestyle interventions in pregnancy that prevent or treat obesity for maternal and fetal weight (primary objective) •determine the effectiveness of various dietary and lifestyle interventions that prevent or treat obesity for obstetric antenatal, intrapartum and postnatal outcomes •evaluate the benefit of the dietary and lifestyle weight management interventions in pregnancy for fetal and neonatal morbidity and mortality •study the potential short- and long-term adverse effects in mother and baby due to dietry and lifestyle in pregnancy. •assess the overall strength of evidence across outcomes for effectiveness and harm of interventions.