⚖️ Pregnancy Tool

Pregnancy Weight Gain Calculator

Calculate your healthy pregnancy weight gain target based on your pre-pregnancy BMI and current week of pregnancy.

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Weight Gain Calculator

Recommended Total Weight Gain
--kg by 40 weeks
Pre-Pregnancy BMI
--
Target Gain By Week
--
kg

Pre-Pregnancy BMIRecommended Gain (Single)Recommended Gain (Twins)
Underweight (<18.5)12.5 - 18 kg22.5 - 28 kg
Normal (18.5-24.9)11.5 - 16 kg17 - 24.5 kg
Overweight (25-29.9)7 - 11.5 kg14 - 22.5 kg
Obese (≥30.0)5 - 9 kg11.5 - 19 kg

About Pregnancy Weight Gain

Gaining the right amount of weight during pregnancy is crucial for your health and your baby's development. The Institute of Medicine (IOM) provides guidelines based on your pre-pregnancy Body Mass Index (BMI).

Where does the weight go? In a typical 14 kg weight gain:

  • Baby: 3 - 3.6 kg
  • Larger breasts: 0.9 - 1.4 kg
  • Larger uterus: 0.9 - 1.4 kg
  • Placenta: 0.7 kg
  • Amniotic fluid: 0.9 kg
  • Increased blood volume: 1.4 - 1.8 kg
  • Increased fluid volume: 0.9 - 1.4 kg
  • Fat stores (for delivery and breastfeeding): 2.7 - 3.6 kg