Weight gain during pregnancy

KEY POINTS

  • It’s best to start pregnancy at a healthy weight. Talk to your provider to find out a healthy weight for you before you get pregnant.

  • Gaining too much or too little weight during pregnancy can be harmful to you and your baby.

  • Don’t ever try to lose weight during pregnancy.

  • You only need about 300 extra calories a day during pregnancy to support your baby’s growth and development.

Is weight gain important during pregnancy?

Yes. Gaining the right amount of weight during pregnancy can help protect your health and the health of your baby. 

If you gain too little weight during pregnancy, you’re more likely than other women to have a premature baby or a baby with low birthweight. A premature baby is born too early, before 37 weeks of pregnancy. Low birthweight means your baby is born weighing less than 5 pounds, 8 ounces.

If you gain too much weight during pregnancy, you’re more likely than other women to:

  • Have a premature baby. Premature babies may have health problems at birth and later in life, including being overweight or obese. Being obese means you have an excess amount of body fat. 
  • Have a baby with fetal macrosomia. This is when your baby is born weighing more than 8 pounds, 13 ounces. Having a baby this large can cause complications, like problems during labor and heavy bleeding after birth.  
  • Need a cesarean birth (also called c-section). This is surgery in which your baby is born through a cut that your health care provider makes in your belly or uterus.
  • Have trouble losing weight after your baby’s birth. This can increase your risk for health conditions like diabetes and high blood pressure. 

How much weight should you gain during pregnancy?

This depends on your health and your body mass index (also called BMI) before you get pregnant. BMI is a measure of body fat based on your height and weight. To find out your BMI, go to www.cdc.gov/bmi.

Your health care provider uses your BMI before pregnancy to figure out how much weight you should gain during pregnancy. First, let’s look at BMI:

  • Underweight = BMI less than 18.5
  • Healthy weight = BMI 18.5 to 24.9
  • Overweight = BMI 25 to 29.9
  • Obese = BMI more than 30

If you’re pregnant with one baby:

  • If you were underweight before pregnancy, you want to gain about 28 to 40 pounds during pregnancy. 
  • If you were at a healthy weight before pregnancy, you want to gain about 25 to 35 pounds during pregnancy. 
  • If you were overweight before pregnancy, you want to gain about 15 to 25 pounds during pregnancy. 
  • If you were obese before pregnancy, you want to gain about 11 to 20 pounds during pregnancy. 

If you’re pregnant with twins:

  • If you were at a healthy weight before pregnancy, you want to gain about 37 to 54 pounds during pregnancy. 
  • If you were overweight before pregnancy, you want to gain about 31 to 50 pounds during pregnancy. 
  • If you were obese before pregnancy, you want to gain about 25 to 42 pounds during pregnancy. 

If you’re overweight or obese and are gaining less than the recommended amounts, talk to your provider. If your baby is still growing well, your weight gain may be fine.  

Gaining weight slowly and steadily is best. Don't worry too much if you don’t gain any weight in the first trimester, or if you gain a little more or a little less than you think you should in any week. You may have some growth spurts—this is when you gain several pounds in a short time and then level off. Don’t ever try to lose weight during pregnancy.  

If you’re worried about your weight gain, talk to your health care provider. 

How can you track your weight gain during pregnancy?

Your provider checks your weight at each prenatal care visit. Use our weight-gain tracking chart to track your weight yourself.

Where do you gain the weight during pregnancy?

If you’re at a healthy weight before pregnancy and gain 30 pounds during pregnancy, here’s where you carry the weight:

  • Baby = 7.5 pounds
  • Amniotic fluid = 2 pounds. Amniotic fluid surrounds the baby in the womb.
  • Blood = 4 pounds
  • Body fluids = 4 pounds
  • Breasts = 2 pounds
  • Fat, protein and other nutrients = 7 pounds
  • Placenta = 1.5 pounds. The placenta grows in your uterus (also called womb) and supplies the baby with food and oxygen through the umbilical cord.
  • Uterus = 2 pounds. The uterus is the place inside you where your baby grows

Last reviewed: November, 2016

Is weight gain important during pregnancy?

Yes. Gaining the right amount of weight during pregnancy can help protect your health and the health of your baby. 

If you gain too little weight during pregnancy, you’re more likely than other women to have a premature baby or a baby with low birthweight. A premature baby is born too early, before 37 weeks of pregnancy. Low birthweight means your baby is born weighing less than 5 pounds, 8 ounces.

If you gain too much weight during pregnancy, you’re more likely than other women to:

  • Have a premature baby. Premature babies may have health problems at birth and later in life, including being overweight or obese. Being obese means you have an excess amount of body fat. 
  • Have a baby with fetal macrosomia. This is when your baby is born weighing more than 8 pounds, 13 ounces. Having a baby this large can cause complications, like problems during labor and heavy bleeding after birth.  
  • Need a cesarean birth (also called c-section). This is surgery in which your baby is born through a cut that your health care provider makes in your belly or uterus.
  • Have trouble losing weight after your baby’s birth. This can increase your risk for health conditions like diabetes and high blood pressure. 

How much weight should you gain during pregnancy?

This depends on your health and your body mass index (also called BMI) before you get pregnant. BMI is a measure of body fat based on your height and weight. To find out your BMI, go to www.cdc.gov/bmi.

Your health care provider uses your BMI before pregnancy to figure out how much weight you should gain during pregnancy. First, let’s look at BMI:

  • Underweight = BMI less than 18.5
  • Healthy weight = BMI 18.5 to 24.9
  • Overweight = BMI 25 to 29.9
  • Obese = BMI more than 30

If you’re pregnant with one baby:

  • If you were underweight before pregnancy, you want to gain about 28 to 40 pounds during pregnancy. 
  • If you were at a healthy weight before pregnancy, you want to gain about 25 to 35 pounds during pregnancy. 
  • If you were overweight before pregnancy, you want to gain about 15 to 25 pounds during pregnancy. 
  • If you were obese before pregnancy, you want to gain about 11 to 20 pounds during pregnancy. 

If you’re pregnant with twins:

  • If you were at a healthy weight before pregnancy, you want to gain about 37 to 54 pounds during pregnancy. 
  • If you were overweight before pregnancy, you want to gain about 31 to 50 pounds during pregnancy. 
  • If you were obese before pregnancy, you want to gain about 25 to 42 pounds during pregnancy. 

If you’re overweight or obese and are gaining less than the recommended amounts, talk to your provider. If your baby is still growing well, your weight gain may be fine.  

Gaining weight slowly and steadily is best. Don't worry too much if you don’t gain any weight in the first trimester, or if you gain a little more or a little less than you think you should in any week. You may have some growth spurts—this is when you gain several pounds in a short time and then level off. Don’t ever try to lose weight during pregnancy.  

If you’re worried about your weight gain, talk to your health care provider. 

How can you track your weight gain during pregnancy?

Your provider checks your weight at each prenatal care visit. Use our weight-gain tracking chart to track your weight yourself.

Where do you gain the weight during pregnancy?

If you’re at a healthy weight before pregnancy and gain 30 pounds during pregnancy, here’s where you carry the weight:

  • Baby = 7.5 pounds
  • Amniotic fluid = 2 pounds. Amniotic fluid surrounds the baby in the womb.
  • Blood = 4 pounds
  • Body fluids = 4 pounds
  • Breasts = 2 pounds
  • Fat, protein and other nutrients = 7 pounds
  • Placenta = 1.5 pounds. The placenta grows in your uterus (also called womb) and supplies the baby with food and oxygen through the umbilical cord.
  • Uterus = 2 pounds. The uterus is the place inside you where your baby grows

Last reviewed: November, 2016