Your target weight gain for the second trimester (as well as the third trimester) is 9-16 pounds, which is considerably more than that the recommended 2-4 pounds for the first trimester. If, due to pregnancy discomforts, such as morning sickness, you had a difficult first trimester and did not gain much weight, this is a good time to increase your calories to try to make up some of the weight gain. If you gained too much weight in the first trimester, focus on staying active, and filling your plate with lower-calorie yet nutrient-rich fruits and vegetables.
Keep your target goal weight gain in mind. The recommended total pregnancy weight gain is 25-35 pounds for women whose Body Mass Index (BMI) is in the normal range, between 20 and 25.
If you were overweight at the start of pregnancy, your recommended weight gain is 15-25 pounds. Obese women should gain at least 15 pounds. If you started underweight, the recommended weight gain is 28-40 pounds. If you're expecting twins, you should aim for a total gain of about 35-45 pounds.