Pregnancy Weight Gain Calculator
This calculator provides a recommended weight gain schedule based on IOM (Institute of Medicine) guidelines for pregnancy weight gain.
Recommended Weight Gain During Pregnancy
| Pre-pregnancy BMI | BMI | Total Weight Gain Range | Rates of Weight Gain (2nd and 3rd trimester) |
| Underweight | < 18.5 | 28-40 lbs | 1-1.3 lbs/week |
| Normal weight | 18.5-24.9 | 25-35 lbs | 0.8-1 lbs/week |
| Overweight | 25-29.9 | 15-25 lbs | 0.5-0.7 lbs/week |
| Obese | ≥ 30 | 11-20 lbs | 0.4-0.6 lbs/week |
Healthy Weight Gain During Pregnancy
Gaining the right amount of weight during pregnancy is important for both mother and baby’s health. The Institute of Medicine provides guidelines based on pre-pregnancy BMI:
Why Weight Gain Matters
Appropriate weight gain helps ensure:
- Healthy fetal growth and development
- Proper nutrient stores for breastfeeding
- Reduced risk of pregnancy complications
- Easier return to pre-pregnancy weight
Weight Distribution
Pregnancy weight isn’t just fat – it’s distributed across:
- Baby: 7-8 lbs
- Placenta: 1-2 lbs
- Amniotic fluid: 2 lbs
- Uterus: 2 lbs
- Breast tissue: 2 lbs
- Blood volume: 4 lbs
- Fluids: 4 lbs
- Fat stores: 6-8 lbs
Tips for Healthy Gain
- Focus on nutrient-dense foods
- Eat small, frequent meals
- Stay active with doctor’s approval
- Monitor weight regularly
- Consult your healthcare provider about your individual needs