How much weight you should gain during pregnancy is based on your body mass index (BMI) before pregnancy. BMI is an indicator of body fat calculated from weight and height.

Weight gain recommendations for women pregnant with one baby

Weight gain recommendations for women pregnant with twins

If you’re pregnant with triplets or more, talk to your health care provider about your weight gain goals.

^*All recommendations are from the Institute of Medicine, with the exception of underweight women with twins. Source: Luke B, Hediger ML, Nugent C, Newman RB, Mauldin JG, Witter FR, et al. Body mass index-specific weight gains associated with optimal birth weights in twin pregnancies. J Reprod Med. 2003; 48:217–24.

A previous study found that only about 1 in 3 women gained the recommended amount of weight during pregnancy. About 1 in 5 women gained below pregnancy weight gain recommendations and 1 in 2 gained above recommendations.

Gaining less than the recommended amount of weight in pregnancy is associated with delivering a baby who is too small. Some babies born too small may have difficulty starting breastfeeding, may be at increased risk for illness, and may experience developmental delays (not meeting the milestones for his or her age).

Gaining more than the recommended amount of weight in pregnancy is associated with having a baby who is born too large, which can lead to delivery complications, cesarean delivery, and obesity during childhood. Gaining more than the recommended amount of weight can also increase the amount of weight you hold on to after pregnancy, which can lead to obesity.

How much weight you should gain during pregnancy depends on your body mass index (BMI) before getting pregnant.

If you have:

• Underweight (BMI of less than 18.5), you should gain 28 to 40 pounds
• Normal weight (BMI of 18.5 to 24.9), you should gain 25 to 35 pounds
• Overweight (BMI of 25 to 29.9), you should gain 15 to 25 pounds
• Obesity (BMI of 30 or greater), you should gain no more than 11 to 20 pounds

Talk to your doctor, nurse, or midwife about how much weight is safe to gain during pregnancy.

How many calories you need depends on your weight gain goals. Your provider can tell you what your goal should be, based on things like your weight before pregnancy, your age, and how fast you gain weight. The general recommendations are:

• In the first trimester of pregnancy, you probably do not need extra calories
• In the second trimester, you usually need about 340 extra calories
• In the last trimester, you may need around 450 extra calories per day
• During the final weeks of pregnancy, you may not need extra calories

Keep in mind that not all calories are equal. You should eat healthy foods that are packed with nutrients - not "empty calories" such as those found in soft drinks, candies, and desserts.

Know your caloric needs. In general, the first trimester does not require any extra calories. Typically, add about 340 additional daily calories during the second trimester and about 450 additional daily calories during the third trimester.

Work with your health care provider on your weight gain goals. Track your pregnancy weight gain at the beginning and regularly throughout pregnancy. Compare your progress to recommended healthy pregnancy weight gain ranges.

Eat a balanced diet high in whole grains, vegetables, fruits, low fat dairy, and lean protein. Use the MyPlate plan to see the daily food group targets that are right for you at your stage of pregnancy. Limit added sugars and solid fats found in soft drinks, desserts, fried foods, whole milk, and fatty meats. Most foods are safe to eat during pregnancy, but you will need to use caution with or avoid certain foods. Talk with your health care provider.

Work up to or maintain at least 150 minutes of moderate intensity aerobic activity (such as brisk walking) per week. 150 minutes may sound overwhelming, but you can break up your daily physical activity into smaller chunks of time. Physical activity is healthy and safe for most pregnant women. Talk to your health care provider about any physical activity restrictions.

Why is gaining a healthy amount of weight during pregnancy important?

Gaining an appropriate amount of weight during pregnancy helps your baby grow to a healthy size. But gaining too much or too little weight may lead to serious health problems for you and your baby.

According to experts, gaining too much weight during pregnancy raises your chances for developing gestational diabetes (diabetes during pregnancy) and high blood pressure during pregnancy. It also increases your risk for type 2 diabetes and high blood pressure later in life. If you’re overweight or have obesity when you get pregnant, your chances for health problems may be even higher. You could also be more likely to have a cesarean section (C-section).

Gaining a healthy amount of weight helps you have an easier pregnancy and delivery. It may also help make it easier for you to get back to your normal weight after delivery. Research shows that recommended amounts of weight gain during pregnancy can also lower the chances that you or your child will have obesity and weight-related problems later in life.

How much weight should I gain during my pregnancy?

How much weight you should gain depends on your body mass index (BMI) before pregnancy. BMI is a measure of your weight in relation to your height. You can use a formula to calculate your BMI online.

The general weight-gain advice below is for women having only one baby.

It’s important to gain weight very slowly. The old myth that you’re “eating for two” is not true. During the first 3 months, your baby is only the size of a walnut and doesn’t need many extra calories. The following rate of weight gain is advised

• 1 to 4 pounds total in the first 3 months
• 2 to 4 pounds each month from 4 months until delivery

Talk to your health care professional about how much weight gain is appropriate for you. Work with him or her to set goals for your weight gain. Take into account your age, weight, and health. Track your weight at home or when you visit your health care professional.

Don’t try to lose weight if you’re pregnant. Your baby needs to be exposed to healthy foods and low-calorie beverages (particularly water) to grow properly. Some women may lose a small amount of weight at the start of pregnancy. Speak to your health care professional if this happens to you.