How much weight gain is healthy for you and your baby?

Weight gain is an important part of pregnancy. The recommended amount of weight gain during pregnancy depends on your body mass index (BMI) before pregnancy. Knowing the range of weight gain that’s right for you will help you gain enough weight without gaining too much.

You can find out your pre-pregnancy BMI by:

  • using our online calculator
  • using the following formula: BMI = weight(kg)/height(m)²
  • talking to your health care provider

It is important to gain within the recommended guidelines for the health of you and your baby.

How much weight gain is healthy for you and your baby?

Pre-pregnancy BMI

Weight category

Recommended total weight gain for pregnancy

Recommended weight gain rate in 2nd and 3rd trimesters*

less than 18.5 Underweight 12.5–18 kg (28–40 lbs.) 0.44–0.58 kg/week (1.0–1.3 lbs./week)
18.5–24.9 Healthy weight 11.5–16 kg (25–35 lbs.) 0.35–0.50 kg/week (0.8–1.0 lbs./week)
25.0–29.9 Overweight 7–11.5 kg (15–25 lbs.) 0.23–0.33 kg/week (0.5–0.7 lbs./week)
30 or over Obese 5–9 kg (11–20 lbs.) 0.17–0.27 kg/week (0.4–0.6 lbs./week)

* These calculations assume a 0.5–2.0 kg (1.1–4.4 lbs.) weight gain in the first trimester.

Reprinted with permission from the National Academy of Sciences, courtesy of the National Academies Press, Washington, D.C. Retrieved from 

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