The average weight gain during pregnancy varies according to multiple factors. What you should know, though, when thinking of having a baby, is that regardless of your current weight, you are expected to add a few pounds, and that's perfectly normal.
But don't go overboard: just because you are going to have a baby, you don't have to take literally the saying "eat for two". Actually, you should add, on average, around 300 calories to your current diet. More precisely, during your second trimester, you should add 340 calories, while during your last trimester, the amount should go up to a plus of 450 calories.
So what is the average weight gain during pregnancy, after all? If you have an average weight and a normal BMI of 18.5 to 24.9, then the average weight gain during pregnancy should be of 25 to 35 pounds. If you are underweight, and your BMI is below 18.5, your average weight gain during pregnancy should be of 28 to 40 pounds.
Last but not least, if you're overweight, and your BMI is higher than 25, your average weight gain during pregnancy should be between 11 and 20 pounds.
But what if you're carrying twins? In this particular case, the average weight gain during pregnancy should be of 37 to 54 pounds (if you have a healthy weight, for starters, and lower/higher if you're underweight/overweight). The calorie intake for a woman carrying twins should range between 3000 to 3500 calories a day.
Average Weight Gain during Pregnancy by Week
The rule states that you are going to gain 2 to 4 pounds during the first 3 months of pregnancy, after which you will add roughly 1 pound a week.
How to Gain the Right Amount of Weight during Pregnancy
If you're worried that you are going to either eat too much or too less and harm your future baby, here are some guidelines that will help you stick to the average weight gain during pregnancy.
The rule of thumb is to eat small, but frequent meals. Separate them into about 6 meals a day. Then remember to choose only healthy food - but don't be very hard on yourself if you suddenly feel like splurging on a Big Mac every once in a while!
Make sure your pregnancy menu includes a variety of foods such as bread, pasta, rice, cereals, fruit, veggies, meat, fish, eggs and dairy products. Just remember to go for the low-fat or nonfat varieties, especially if you are overweight. Limit the sugary food intake to your late nighttime cravings, for instance.