Exercising and weight gain during pregnancy

by Kaiser Permanente |
Black pregnant woman chopping vegetables in kitchen.

When you’re pregnant, you should expect to gain weight. Extra weight helps you support your growing baby. But gaining too much or too little weight can cause health concerns or, in rare cases, problems during your labor and birth process.

How much weight should I gain during pregnancy?

The amount of weight you gain during pregnancy depends on your body mass index (BMI) before you became pregnant. If you don’t know your BMI, you can use our BMI calculator at kp.org/bmi or ask your clinician. Find your BMI below to see how much weight gain is recommended for a healthy pregnancy:


Pre-pregnancy BMI: less than 18.5

Total weight gain: 28 to 40 lbs.

Rates of weight gain in 2nd and 3rd trimesters: about 1 lb. per week*

Normal weight

Pre-pregnancy BMI: 18.5 to 24.9

Total weight gain: 25 to 35 lbs.

Rates of weight gain in 2nd and 3rd trimesters: about 1 lb. per week*


Pre-pregnancy BMI: 25.0 to 29.9

Total weight gain: 15 to 25 lbs.

Rates of weight gain in 2nd and 3rd trimesters: about 1/2 lb. per week*


Pre-pregnancy BMI: 30.0 or more

Total weight gain: 11 to 20 lbs.

Rates of weight gain in 2nd and 3rd trimesters: about 1/2 lb. per week*

*Institute of Medicine, 2009

Your clinician will track your weight on a graph that you’ll both review throughout your pregnancy to see if you’re on track. You’ll be weighed at each prenatal appointment.

Most clinicians recommend weighing yourself first thing in the morning. After you get up, empty your bladder and weigh yourself without clothes on. This can give the most accurate measurement.

Remember, pregnancy is not the time to go on any type of weight-loss diet. But gaining more weight than recommended puts added stress on your body too, and it increases your risk of gestational diabetes, high blood pressure, and cesarean (C-section) delivery. Too much weight gain can also increase the chances your baby will develop obesity or diabetes in childhood or later in life. To help you have a healthy pregnancy, your clinician will work with you to set a weight goal that’s right for you.

What can I do to have a healthy pregnancy?

The best things you can do for you and your baby are to eat healthy foods, get regular exercise, avoid alcohol and smoking, and go to your prenatal appointments. Here are a few healthy eating and exercise tips for pregnancy.

Healthy eating tips

  • Eat 3 balanced meals per day, plus 1 to 2 healthy snacks.
  • Eat a variety of foods from all the food groups.
  • Make sure to get enough calcium and folic acid.
  • Don’t “eat for 2.” The number of calories you need during pregnancy is based on your BMI and trimester, but you usually only need an extra 200 to 300 calories per day. For reference, you take in 200 to 300 calories with half a peanut butter sandwich and a glass of low-fat milk.
  • Avoid sweetened drinks (like juice, soda, and specialty coffee drinks), fried foods, and desserts.
  • It’s not a good idea to cut out food groups or start restrictive diets during this time.

Exercise tips

Staying active during pregnancy is great for you and your baby. Exercise may help you have more energy throughout the day. It can also help prepare your body for the birthing process.

  • Aim for at least 30 minutes of physical activity per day on most days of the week unless your clinician tells you otherwise.
  • Exercise can be moderate, which means you should be able to talk in short phrases while exercising
  • It’s OK if your heart rate increases and you sweat.
  • Drink water before, during, and after exercise.
  • If you’re already physically active, you can continue moderate-intensity exercise throughout your pregnancy.
  • If you’re not already physically active, you can start with a daily 15-minute walk and gradually increase to 30 minutes of moderate-intensity exercise on most days. You can try using an elliptical machine or stationary bike, swimming, or doing modified yoga or Pilates.

As you progress in your pregnancy, you will need to avoid certain types of exercise. This includes sit-ups and some yoga poses. If you need to lie flat on your back to do an exercise, you should skip it.

After you know you’re pregnant, steer clear of all contact sports like soccer or basketball. It’s not a good idea to go horseback riding or scuba diving. Exercises at high altitudes, or at 6,000 feet or more above sea level, should be avoided unless that is where you live year-round. Always check with your clinician if you have any questions about which exercises are safe for you.

This article has been created by a national group of Kaiser Permanente ob-gyns, certified nurse-midwives, pediatricians, lactation consultants and other specialists who came together to provide you with the best pregnancy, birth, postpartum, and newborn information.

Some of the content is used and adapted with permission of The Permanente Medical Group.