Pregnancy Weight Gain Calculator
Enter your height and pre-pregnancy weight for the recommended total gain and weekly rate. Based on the IOM/CDC guidelines.
More in the pregnancy guides, including prenatal vitamins and what happens at each prenatal visit.
Pregnancy weight gain questions
- How much weight should I gain during pregnancy?
- It depends on your pre-pregnancy BMI. The Institute of Medicine ranges, published by the CDC, are 28 to 40 lb if you were underweight, 25 to 35 lb at a healthy weight, 15 to 25 lb if overweight, and 11 to 20 lb if obese, for a single baby. Your provider may adjust this for your situation.
- How is the recommended gain calculated?
- It comes from your pre-pregnancy BMI, which is your weight and height before pregnancy. That BMI maps to one of four ranges. Most of the gain happens after the first trimester, which is usually only 1 to 4.5 lb, then settles into a fairly steady weekly rate through the second and third trimesters.
- What if I gain more or less than recommended?
- Being a little outside the range is common and not a problem on its own. The ranges are a guide, not a target to police. Do not restrict eating to hit a number. If your gain is well outside the range or changes suddenly, mention it to your OB or midwife, who can look at the whole picture.
- What about twins?
- Twin pregnancies have higher ranges: about 37 to 54 lb at a healthy weight, 31 to 50 lb if overweight, and 25 to 42 lb if obese. The IOM does not publish a specific range for underweight twin pregnancies, so your provider sets a target with you. Tick the twins box in the calculator for these figures.