Weight gain in pregnancy recommendations have changed over the years. Used to be the that doctors told patients "you are eating for two" and gave encouragement to gain lots of weight. We now know that excess weight gain can increase risks of Cesarean section, maternal obesity, diabetes, preeclampsia and possible diabetes or obesity in offspring. The recommendation now is to gain a set amount of weight based on your pre-pregnancy BMI with lower BMIs gaining more weight. If you are underweight (BMI < 18.5) then the recommendation is to gain 28 - 40 lbs total for the entire pregnancy. For normal weight (BMI 18.5 - 24.9), weight gain recommendation is 25 - 35 lbs. For overweight patients (BMI 25.0 - 29.9) then limit to 15 to 25 lbs. And for obese patients (BMI >or= 30) then the limit is 11 to 20 lbs. And the recommendation may be less for the extremely obses maternal patient. These recommendations are for singleton pregnancies so multiples would be expected to gain more. In general it is recommended 1/2 to 1 lb weight gain per week in the second and third trimester. In the first trimester, some women may not gain much weight. Weight gain should definitely be limited to 1 lb per week in the first trimester.