During pregnancy, women should gain during 25-35 pounds. Women who are overweight should gain 15 to 25 pounds and those who are underweight should gain 35 to 40 pounds. These are only average figures, and there may be a little normal variation.
However, most of the weight gain in pregnancy starts from the second trimester and the maximum gain is in the third trimester. There is generally little or no weight gain in the first trimester. So excessive weight gain in the first trimester can also be a sign of some diseases like diabetes, high blood pressure, etc. which are common complications in pregnancy and so weight gain more than this should be checked up by your gynaecologist.
Her gynaecologist can check her up to see whether the weight gain is normal or due to some disease.
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