Too fast weight gain in late pregnancy is usually caused by too little activity, too much calorie intake, gestational diabetes, etc. It can be controlled by moderate exercise, dietary adjustments, use of insulin and so on. 1. Too little activity: In terms of lifestyle, pregnant women can do some moderate exercise, such as yoga for pregnant women, walking after meals, etc., which will help to consume calories, and not to sit and lie down for a long time. 2. Excessive calorie intake: Pregnant women should also eat less calorie-rich food, such as fried food, high sugar food, etc., should be supplemented with high-quality proteins, more vegetables, and eat some fruits in moderation. 3. Gestational diabetes: If a pregnant woman has gestational diabetes, it may lead to abnormal blood glucose metabolism, resulting in rapid weight gain, which then requires the use of insulin for treatment. Too rapid weight gain in late pregnancy usually leads to oversized fetus, making the risk of cesarean section and difficult labor increase, so weight control should be appropriate, and it is recommended that pregnant women with rapid weight gain go to the hospital for examination to rule out some gestational diseases, such as gestational diabetes mellitus, etc., and take the appropriate way to intervene under the guidance of the doctor to prevent rapid weight gain.