1. Physical changes at 31 weeks of pregnancy At 31 weeks of pregnancy, the baby has grown into the size of a small watermelon and weighs about 1.5 kilograms. At this time, the pregnant mother\’s belly is getting bigger and bigger because it has expanded to below the sternum. In addition, pregnant mothers may feel edema in their legs and feet, which is caused by compression of the veins and blood vessels. 2. How to relieve leg edema 1. Get more rest: Maintaining an appropriate rest period can reduce leg edema. 2. Proper exercise: Proper exercise can promote blood circulation. 3. Wear comfortable shoes