Let’s be honest — most of us cringe at the thought of stepping on the scale. In fact, many of us grew up during a time when constant messaging tried to tell us that our weight is tied to our worth.

pregnant woman on scale - How Much Weight Should I Gain in Pregnancy?


While a burgeoning body positivity movement has helped decrease our culture’s obsession with the number on the scale, weight is still an important clinical measurement during pregnancy. This means that at every prenatal appointment, your provider will weigh you and make note of the reading.

Unfortunately, weight gain during pregnancy can cause anxiety, especially if weight and body image have been an issue in the past. This is often compounded by already high anxiety and fear when pregnant after loss.

Why is weight significant when pregnant? How much weight should you gain in pregnancy? How are the extra pounds distributed throughout the pregnant body? Read on for answers to these questions and more!

Why Does Weight Matter During Pregnancy?

Too little or too much gained can cause problems for the parent or the baby. Research shows that a gestational parent who gains too little weight could give birth to a baby with low birth weight, low blood sugar, or feeding problems. These conditions can lead to an extended hospital stay as well as respiratory, cardiovascular, or digestive issues.

Meanwhile, gaining too much weight during pregnancy comes with an elevated risk of gestational diabetes and preeclampsia for the expectant parent. Both of these conditions increase the chances of preterm delivery and C-section, meaning a longer recovery time for the birthing parent and additional medical care for the baby[1]“Weight Gain During Pregnancy,”  Centers for Disease Control and Prevention, https://www.cdc.gov/reproductivehealth/maternalinfanthealth/pregnancy-weight-gain.htm.

What’s the Right Amount of Weight to Gain When Pregnant?

The appropriate amount of weight you should gain during pregnancy is linked to your pre-pregnancy body mass index, or BMI[2]“Healthy Weight Gain During Pregnancy,” Institute of Medicine and National Research Council of the National Academies, https://webassets.nationalacademies.org/whattogain/. The formula for calculating BMI is: Your pre-pregnancy weight (in kilograms) divided by the square of your height (in meters)[3]“Calculate Your Body Mass Index,” National Institute of Health: National Heart, Lung, and Blood Institute, https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm.

If your pre-pregnancy BMI falls within the normal range, a weight gain of 25-35 pounds is ideal. In that case, experts recommend gaining about 1-4 pounds during the first trimester of pregnancy. However, some women lose a few pounds in the first three months because of nausea and loss of appetite. During the second and third trimesters, gradual weight gain is best, so aim for an increase of one pound per week. That’s about 12-14 pounds during the second trimester and around 8-10 pounds in the last trimester when the baby’s growth tapers off as there’s less room in the uterus.

For those who begin pregnancy with a BMI that puts them in the underweight category, the overall weight gain should be slightly higher — approximately 28-40 pounds. Conversely, people with a higher BMI should try to gain less weight while pregnant: 15-25 pounds if overweight and 11-20 if obese[4]“Weight Gain During Pregnancy,” The American College of Obstetricians and Gynecologists, Committee Opinion, Number 548, January 2013, … Continue reading. In addition, the recommended weight gain for those who are carrying twins is higher than with a single baby.

It’s important to remember that these numbers are broad recommendations, and weight gain in pregnancy can vary widely. Try not to worry if your appetite and, therefore, weight gain, fluctuate some. As long as your overall weight gain is on target, you’re on the right track. And if you have questions or concerns, ask your prenatal care provider.

How Can I Make Sure My Pregnancy Weight Gain is on Track?

If you’re nervous about keeping your pregnancy weight gain on target, here are a few tips to ease your mind.

  • Know your pre-pregnancy weight. If you haven’t been on the scale in a while, weigh yourself at home. Do this as before your first prenatal appointment, which often doesn’t happen until a few weeks into pregnancy. This number is important for calculating your BMI.
  • Eat a healthy, balanced diet. Choose fresh fruits and vegetables in a variety of colors, lean meats and fish, complex carbohydrates, and good fats, like olive or avocado oil.
  • Limit added sugar and unhealthy fats. While an occasional treat is OK, it’s important not to go overboard with sweets or processed carbs.
  • Take in the right number of calories. You don’t need any additional calories during the first trimester, but aim for an extra 300-350 calories per day during the second trimester. In the third trimester, shoot for about 450-500 additional calories.
  • Stay moderately active. If you’re already active, continue exercising throughout pregnancy. If exercise isn’t already a part of your routine, start with safe, low-impact activities like walking, yoga, or swimming during pregnancy.

Where Does the Extra Weight Go During Pregnancy?

You might be wondering, if the average baby weighs about seven and a half pounds, how is the weight gained during pregnancy distributed? There’s more to the pregnant body than a baby. And while every pregnant body is different, here is a breakdown of the averages[5]Pregnancy Weight Gain,” American Pregnancy Association, https://americanpregnancy.org/healthy-pregnancy/pregnancy-health-wellness/pregnancy-weight-gain-968/.

  • Baby: 7.5 pounds
  • Placenta: 1.5 pounds
  • Amniotic fluid: 2 pounds
  • Uterine enlargement: 2 pounds
  • Breast tissue: 2 pounds
  • Blood volume: 4 pounds
  • Fluids in tissue: 4 pounds
  • Fat stores: 7 pounds

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