Hey Aruna. Congratulation. That is a progress. I hope you are following a routine the prenatal vitamins as prescribed by the doctor. Weight gain issue in pregnancy can be due to many reason. But to understand this better, here are a few tips which will help you to have things in control. Start pregnancy at a healthy weight if possible. Eat balanced meals and refuel often. Drink up (water, that is) Make your cravings constructive. Choose complex carbs. Start a simple walking routine. If you're already moving, don't stop. Make weight a regular discussion. Please feel free to talk to your doctor if you feel you are feeling different about this issue.