Monitoring weight gain during pregnancy

Learn healthy, doctor-recommended ways to monitor and manage pregnancy weight

Monitoring weight gain during pregnancy

The amount of weight you gain — or don’t gain — in pregnancy can have short- and long-term health effects on you and your baby.

Dangers of too much or too little

Excessive weight gain is associated with larger birth weight, which can lead to:

  • Cesarean delivery
  • Operative vaginal delivery needing forceps or a vacuum
  • Shoulder dystocia
  • Low blood sugar after your baby is born
  • Higher incidence of childhood obesity and metabolic syndrome, or increased risk of diabetes

Too much weight gain isn’t healthy, but less isn’t always more. Babies need nutrients to grow. Insufficient weight gain can be associated with smaller birth weight, which can lead to preterm delivery, low blood sugar after the baby is born and an increased risk of perinatal mortality.

Weight gain during pregnancy

Where does that extra weight go? You may think it’s all going to your belly, but it’s actually distributed to other areas as well.

If you gain about 30 pounds, here’s the average breakdown of where that extra weight goes:

  • Baby: 7.5 pounds
  • Placenta: 1.5 pounds
  • Amniotic fluid: 2 pounds
  • Uterine enlargement: 2 pounds
  • Maternal breast tissue: 2 pounds
  • Maternal blood volume: 4 pounds
  • Fluids in maternal tissue: 4 pounds
  • Maternal fat stores: 7 pounds

So how much weight should you gain? That depends on what your body mass index (BMI) is before pregnancy. You can also talk with your provider to determine BMI or use our online calculator. This will help you know how much weight gain is appropriate for you and your baby.

Here are the recommendations:

  • Underweight: Gain 28 to 40 pounds
  • Healthy weight: Gain 25 to 35 pounds
  • Overweight: Gain 15 to 25 pounds
  • Obese: Gain 11 to 20 pounds

Losing weight during pregnancy

If you were overweight or obese before your pregnancy, should you try to lose weight?

The American Congress of Obstetricians and Gynecologists encourages women to begin a nutritious weight reduction program if they are overweight and considering pregnancy. But once you’re pregnant, it isn’t recommended that you try to lose weight. Wait until after delivery to actively try to lose weight.

If you’re gaining more weight than you think you should while pregnant, track your diet for a week and talk to your OB/GYN. Your doctor can make some suggestions to help you eat better without excessive caloric consumption.

How to maintain a healthy weight

To help you stay at a healthy weight while pregnant, follow these tips:

  • Try not to eat more than 350 to 450 extra calories a day. While healthy eating is always important, it’s more important when you’re pregnant because of its direct impact on your baby’s health. Focus on filling your plate with healthy foods, including lots of fruits and vegetables and low-fat dairies. Choose foods that are high in nutrients instead of calories. Learn more about pregnancy-friendly foods.
  • Stay active. Aim for at least 30 minutes of moderate activity every day unless instructed otherwise by your provider. Brisk walking and swimming are good options.
  • Check your weight often. This will help you keep track of your weight gain. You can then make changes in your diet and activity level if needed.
  • Don’t skip the doctor’s office. See your health care provider for all prenatal visits.
  • Get a personalized plan. Your OB/GYN can give you a tailored goal for weight gain during pregnancy based on your pre-pregnancy weight.

Remember, your provider is available to answer any questions you may have about your weight while pregnant. They can also offer advice and support to make sure you and your baby stay healthy during pregnancy and after.

Find a pregnancy care provider.

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Posted In Health Information, Pregnancy, Women's