Pregnancy Weight Gain Calculator
Find your recommended weight gain during pregnancy based on your pre-pregnancy BMI and IOM guidelines.
Recommended Weight Gain
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Pre-pregnancy BMI: — — —
What is Pregnancy Weight Gain Calculator?
The pregnancy weight gain calculator uses your pre-pregnancy Body Mass Index (BMI) to recommend a healthy total weight gain range based on guidelines from the Institute of Medicine (IOM). Gaining the right amount of weight during pregnancy supports your baby's development while reducing risks for both mother and child.
How to use
- 1 Enter your pre-pregnancy height and weight.
- 2 Choose metric (cm/kg) or imperial (in/lbs) units.
- 3 Your pre-pregnancy BMI and recommended total weight gain range appear instantly.
Formula
Example calculation
A woman who is 165 cm tall and weighs 60 kg has a pre-pregnancy BMI of 22.0 (normal weight). Her recommended total weight gain is 11.5–16 kg (25–35 lbs).
Frequently asked questions
Why does pre-pregnancy weight matter?
Your starting BMI determines how much reserve you have and what rate of gain best supports both maternal and fetal health throughout pregnancy.
Is it safe to diet during pregnancy?
Intentional calorie restriction during pregnancy is not recommended. Focus on nutrient-dense foods. Consult your OB or midwife for personalized guidance.
What if I gain more than recommended?
Excessive weight gain increases risks of gestational diabetes, hypertension, cesarean delivery, and postpartum weight retention. Talk to your provider if you're concerned.
What if I gain less than recommended?
Insufficient weight gain can lead to low birth weight and preterm delivery. If you're struggling to gain enough, speak with a registered dietitian.
Do these guidelines apply to twins?
No. The IOM has separate recommendations for twin pregnancies. Consult your healthcare provider for guidance specific to multiples.