We found high-quality evidence that diet or exercise interventions, or both, help to reduce excessive weight gain in pregnancy. They may also reduce caesarean deliveries, especially with combined diet and exercise interventions, and maternal hypertension. In addition, the chances of having a baby over 4 kg and the chances of the newborn having breathing difficulties after birth may be reduced, especially in overweight and obese women. Moderate-intensity exercise appears to be an important part of weight-control strategies in pregnancy; however, more research is needed on side-effects to inform safe guidelines.
High-quality evidence indicates that diet or exercise, or both, during pregnancy can reduce the risk of excessive GWG. Other benefits may include a lower risk of caesarean delivery, macrosomia, and neonatal respiratory morbidity, particularly for high-risk women receiving combined diet and exercise interventions. Maternal hypertension may also be reduced. Exercise appears to be an important part of controlling weight gain in pregnancy and more research is needed to establish safe guidelines. Most included studies were carried out in developed countries and it is not clear whether these results are widely applicable to lower income settings.