Free Pregnancy Weight Gain Calculator
Calculate recommended pregnancy weight gain based on pre-pregnancy BMI following IOM guidelines.
lbs
inches
weeks
Recommended Gain (Low)
25 lbs
Recommended Gain (High)35 lbs
Expected Gain by Now (Low)11.1 lbs
Pre-Pregnancy BMI23.3
Recommended Gain (Low) vs Pre-Pregnancy Weight
IOM Pregnancy Weight Gain Guidelines
Most weight gain occurs in the second and third trimesters, with about 1-2 lbs per week being typical for normal-weight women.
Example Calculation
A 140 lb, 65-inch tall woman at 20 weeks pregnant.
- 01Pre-pregnancy BMI = (140 x 703) / (65 x 65) = 23.3 (Normal)
- 02Recommended total gain = 25-35 lbs
- 03Expected by week 20 = 25 x 0.25 + (25 x 0.75) x 7/27 = 6.25 + 4.9 = 11.1 lbs (low end)
Frequently Asked Questions
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