Pregnant women will not necessarily gain weight if they eat noodles at night, because the principle of diet during pregnancy is to eat less and more, so they can eat a small amount of noodles at night when they are hungry. As long as the total daily calories are not exceeded, it will not cause pregnant women to gain weight. During pregnancy, we should pay attention to control excessive weight gain, especially for pregnant women with a fat body mass index, we should make personalized recipes and calculate the daily calories and the amount of calories per meal. As long as the daily calorie allocation is balanced and not excessive, coupled with proper exercise for pregnant women, it will not lead to obesity and excessive weight gain. It is important to have a balanced and varied diet during pregnancy, not only increasing the amount of high-quality protein every day, but also eating fresh vegetables and the right amount of fruits.