Pregnancy tools
Pregnancy Weight Gain Calculator
How much weight gain is healthy for your pregnancy? Enter your height, pre-pregnancy weight, and current week to see the ACOG-recommended range, personalized for you.
Enter your pre-pregnancy weight above to see your recommended range.
General guidance from the Institute of Medicine (2009) and ACOG Committee Opinion 548. Please always check with your provider.
Understanding Pregnancy Weight Gain
Healthy weight gain during pregnancy supports your baby's growth, builds necessary reserves for breastfeeding, and helps your body prepare for delivery. The recommended amount depends on your pre-pregnancy BMI, which is why the guidelines differ from person to person.
| Pre-pregnancy BMI | Recommended total gain | Weekly pace, 2nd and 3rd trimester |
|---|---|---|
| Under 18.5 | 28–40 lbs | 1–1.3 lbs |
| 18.5–24.9 | 25–35 lbs | 0.8–1 lb |
| 25–29.9 | 15–25 lbs | 0.5–0.7 lb |
| 30 or higher | 11–20 lbs | 0.4–0.6 lb |
Most of the gain happens in the second and third trimesters. In the first trimester, gaining 1 to 4 pounds total is typical. After that, a steady pace of about 0.5 to 1 pound per week (depending on BMI) is a healthy target.
Your provider weighs you at each prenatal visit and looks at the overall trend, not any single number. Fluctuations are normal, and what matters most is a steady, healthy pattern over time.
Common Questions
How much weight should I gain during pregnancy?
It depends on your pre-pregnancy BMI. The ACOG and IOM guidelines recommend 28 to 40 pounds for a BMI under 18.5, 25 to 35 pounds for a BMI of 18.5 to 24.9, 15 to 25 pounds for a BMI of 25 to 29.9, and 11 to 20 pounds for a BMI of 30 or higher. These ranges support healthy outcomes for both you and your baby.
Is most of the weight gain baby?
Your baby accounts for about 7 to 8 pounds at delivery. The rest is distributed across the placenta (about 1.5 lbs), amniotic fluid (about 2 lbs), increased blood volume (about 3 to 4 lbs), breast tissue (about 1 to 3 lbs), uterine growth (about 2 lbs), and necessary fat stores (about 6 to 8 lbs).
When does most weight gain happen?
In the first trimester, most people gain only 1 to 4 pounds total. The majority of weight gain happens in the second and third trimesters at a steady pace. A slow and steady trend is healthier than rapid gains.
What if I am gaining more or less than the range?
A little above or below the range is usually fine. Your provider looks at the overall trend, not any single weigh-in. If you are consistently outside the range, your Garden OB/GYN team can help you adjust your nutrition and activity plan.
Are the guidelines different for twins?
Yes. The IOM recommends higher weight gain for twin pregnancies: 37 to 54 pounds for a BMI of 18.5 to 24.9, 31 to 50 pounds for a BMI of 25 to 29.9, and 25 to 42 pounds for a BMI of 30 or higher. Your provider will set a personalized target.
Questions about your weight gain?
Every body is different, and our providers are here to support a healthy pregnancy at your pace. Explore our due date calculator, baby size tool, and food safety checker.
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