How much weight to gain in pregnancy
Recommended pregnancy weight gain depends on your weight before pregnancy, measured by your pre-pregnancy BMI. This calculator uses the Institute of Medicine (IOM) guidelines to show a healthy total range for your category. Gaining within the range supports a healthier pregnancy for both you and your baby.
Worked example
Someone 165 cm and 60 kg before pregnancy has a normal-range BMI, for which the IOM suggests gaining about 11.5 to 16 kg in total.
The IOM ranges
Underweight before pregnancy: gain more; normal: 11.5 to 16 kg; overweight: less; obese: least. These are for single pregnancies; twins have higher ranges. Your provider gives the final word.
Frequently asked questions
How much weight should I gain in pregnancy?
It depends on your pre-pregnancy BMI. For a normal BMI, the IOM suggests about 11.5 to 16 kg total. Underweight women gain more and overweight women less.
Is weight gain steady?
Usually little gain in the first trimester, then a steadier increase after. Your provider tracks it against your personal range.
Is gain steady through pregnancy?
Most gain happens in the second and third trimesters, often around 0.4 kg per week for a normal starting BMI.
What about twins?
Twin pregnancies have higher recommended ranges. This calculator covers a single baby; ask your provider about multiples.
Is this medical advice?
No. It shows general guideline ranges. Your midwife or doctor gives advice for your pregnancy.