Health
Pregnancy Weight Gain Calculator
IOM-recommended weight gain during pregnancy based on pre-pregnancy BMI.
Inputs
Pregnancy Weight Gain Calculator
Result
Recommended total gain
11.3–15.9 kg
- Pre-pregnancy BMI
- 23.9 (Normal)
- Expected gain by week 20
- 3.6–6 kg
- Weekly rate (T2–T3)
- 0.39–0.5 kg/wk
How it's calculated
Range from IOM 2009 guidelines by pre-pregnancy BMI; first-trimester ~0.5–2 kg, remainder linear over weeks 13–40.
Common questions
Are these targets absolute?
No — they are population guidelines. Your provider may recommend a different range based on your health.
What if I gain outside the range?
Talk to your provider. Consistent tracking matters more than any single week.
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