Skip to main content

Please note: Effective March 8, the Davis Avenue Parking Garage will be closed.

See our Visitor Information Page>

Health library

Pregnancy and weight gain: Where's it all going?

Even if you're already in love with your new baby bump, your expanding figure may take some getting used to at first. So it may help to know a little more about those pregnancy pounds. Let's go over what healthy weight gain means and how your pregnant body carries it. 

Not too little, not too much

Weight gain is, of course, normal and healthy when you're having a baby. But you'll want to gain the amount that your provider recommends. Why? Gaining too much weight could put you at risk for: 

  • Premature delivery. 
  • Having a baby with a high birth weight, which can cause labor complications. 
  • A cesarean birth. 
  • Retaining too much weight after your pregnancy, which could increase your risk for health problems such as diabetes and high blood pressure. 

Gaining too little weight can also be a problem—and now is definitely not the time to lose weight. It could cause your baby to be born too early or to have a low birth weight, either of which could cause your baby to have more health problems than other children.

So how much weight should you gain?

The answer depends a lot on your body mass index (BMI) before pregnancy, which your provider calculates from your height and weight. The American College of Obstetricians and Gynecologists lists these general guidelines for how much you should gain based on your pre-pregnancy BMI weight category:

  • If you were underweight (BMI less than 18.5) = between 28 and 40 pounds.
  • If you were at a healthy weight (BMI 18.5 to 24.9) = about 25 to 35 pounds.
  • If you were overweight (BMI 25 to 29.9) = between 15 and 25 pounds.
  • If you were obese (BMI 30 and above) = between 11 and 20 pounds.

Don't sweat this stuff too much. Your provider can talk to you about how much weight you should gain and how to do that. In most cases, eating around 300 extra calories per day is about right. Your provider will also check your weight regularly during prenatal visits to make sure you're on track. 

But where does it all go?

Let's say you were at a healthy weight before pregnancy and add 30 pounds over the course of these nine months. According to the March of Dimes and the Office on Women's Health, here's where you'd carry that added weight:

  • Baby = 7.5 pounds.
  • Amniotic fluid = 2 pounds.
  • Body fluids = 4 pounds.
  • Blood = 4 pounds.
  • Breasts = 2 pounds.
  • Fat, protein and other nutrients = 7 pounds.
  • Placenta = 1.5 pounds.
  • Uterus = 2 pounds.

Breaking it down is a good reminder that you and your body are working together to create a healthy environment for your little bundle of joy.

More pregnancy news

Exercise can help with healthy weight gain (and much more) when you're pregnant. But what's okay and what's not? Check out this guide to find out more.

Reviewed 1/18/2024

Related stories