All About Pregnancy Weight Gain

Weight gain during pregnancy is essential for the health of both you and your baby. According to leading health authorities like the CDC, Mayo Clinic, and ACOG, how much weight you should gain during pregnancy depends on your pre-pregnancy Body Mass Index (BMI), your body type, whether you’re having multiples, and your general health status—there’s no one-size-fits-all when it comes to pregnancy weight gain. 

Here’s a quick guide to the recommended weight gain:

Key tips:

• No extra calories are needed in the first trimester

• Add ~340 calories/day in the second trimester and ~450 in the third

• Regular exercise (150 minutes/week) and balanced nutrition are encouraged.

Tracking your weight with your healthcare provider helps ensure a healthy pregnancy. In the next sections, we’ll explore the average pregnancy weight gain by week and provide tips on how to manage weight gain effectively, adjust your diet, and stay active safely.

How Much Weight Should You Gain During Pregnancy?

Healthy weight gain during pregnancy is essential for supporting your baby’s growth and development, as well as changes in your own body. But how much weight you “should” gain while pregnant depends on your pre-pregnancy weight and overall health.

Healthcare providers use a measurement known as body mass index (BMI) to determine a healthy and appropriate weight gain range for each individual, keeping pre-pregnancy weight in mind. BMI is a ratio derived by calculating your weight (in kilograms) by your height (in meters), squared. Although not perfect for every individual body, it estimates a measurement of body fat in most cases.

The general rule is that those with a lower "starting" BMI will have a greater recommended pregnancy weight gain than those with a higher starting BMI. Regardless of your pre-pregnancy BMI, the goal is to gain weight gradually, week by week.

This typical weight gain during pregnancy includes not just the baby, but also the placenta, amniotic fluid, increased blood volume, breast tissue, and other necessary physical changes. The average weight gain in pregnancy supports your body’s ability to nourish your baby and prepare for birth and breastfeeding.

Not Gaining Enough Weight During Pregnancy

If you're not gaining weight during pregnancy, especially in the second or third trimester, it's important to speak with your healthcare provider. While some weight fluctuation can be normal, no weight gain during pregnancy can increase the risk of premature birth and low birth weight.

Your provider may recommend nutritional changes, such as increasing your intake of protein, healthy fats, and complex carbohydrates. Adding calorie-dense but nutritious foods like nuts, avocado, eggs, and full-fat dairy can help with healthy pregnancy weight gain.

In some cases, not putting on weight in pregnancy may signal underlying health issues like hyperemesis gravidarum or thyroid disorders. Regular checkups and prenatal care can help monitor your weight gain and ensure both you and your baby stay healthy.

Gaining Too Much Weight During Pregnancy

On the other hand, gaining too much weight during pregnancy can increase the risk of complications such as gestational diabetes, preeclampsia, high blood pressure, and a greater chance of needing a cesarean delivery. It can also lead to long-term weight retention and increase the likelihood of childhood obesity in your baby.

If you're concerned about too much weight gain during pregnancy, your provider might suggest changes like eating smaller, more balanced meals, watching portion sizes, and incorporating regular physical activity, such as walking, swimming, or prenatal yoga—if it's safe for you.

Wondering how to not gain too much weight during pregnancy? Focus on nutrient-rich foods, stay hydrated, and follow your healthcare provider’s guidance. Remember, the goal is not to diet during pregnancy but to gain weight gradually and healthfully, supporting your baby’s development and your own well-being.

Pregnancy Weight Gain Chart

To help you visualize the general recommendations above, we’ve created a pregnancy weight gain chart to show the recommended weight gain each week in pounds (lb) for both single babies and twins. Talk to your healthcare provider about using the chart to help guide and manage your pregnancy weight gain.

Your healthcare provider will check your weight at your first prenatal care visit. You’ll also discuss your BMI and what it means for your pregnancy. At each visit after that, you’ll track your pregnancy weight gain together, and you can use the above chart as a general guideline.

You can also use the visual below to track your pregnancy weight gain:

Most likely, you’ll gain weight gradually, but your provider will help you along if you gain too little or too much, which could cause issues for you and/or your newborn, as we mentioned earlier in our guide. 

Actively gaining or losing weight while pregnant may not be necessary, even if you start your pregnancy underweight or overweight. It’s best to consult your healthcare provider, who can offer ways to adjust your diet and daily routine.

Pregnancy Weight Gain Graph

Our graph below is another handy way to help you stay on track with your weight gain during pregnancy and see what is recommended based on your pre-pregnancy BMI.

Pregnancy Weight Gain: Week by Week

Gradual weight gain during pregnancy is ideal, and tracking your weight week by week within each trimester can help you understand your overall weight gain. 

This article offers guidelines for weight gain during an average pregnancy with a single baby for individuals who start with a normal BMI. If you are expecting multiples or have a lower or higher pre-pregnancy BMI, consult your healthcare provider to discuss your ideal weight gain through pregnancy. You can use this guide for general information.

Pregnancy Weight Gain: First Trimester

Your first trimester typically includes weeks 1 to 13. Remember that during these early weeks of pregnancy, you probably won’t see steady weight gain. So, how much weight should you gain in the first trimester? Everyone is different, but the average weight gained in the first trimester (during the first three months) for a normal pregnancy is generally up to five pounds—although it’s also possible to lose weight during this initial period.

• Weeks 1 to 4. During the first month of pregnancy, you may not realize you are pregnant. You might not feel any symptoms or notice any weight gain. This has to do with the way many healthcare providers track your pregnancy, using the Last Menstrual Period (LMP) method. 

  • If your pregnancy starts at the beginning of your last menstrual period, then you wouldn’t have ovulated (and, therefore, conceived) until after 14 days (assuming you have a 28-day cycle). 

  • Because you wouldn’t be technically pregnant until week 3, it’s rare to gain any weight during your first month of pregnancy. 

• Weeks 5 to 8. Although your body will be going through quite a bit of change during these weeks, you still might not gain much weight. In fact, if you’re experiencing morning sickness, it’s possible to lose weight during this time. 

  • Hormonal changes might cause digestive issues, prompting nausea, vomiting, or specific food aversions.

    • However, these same hormones might cause your breasts to get bigger as milk-producing glands enlarge, which could contribute to some minor weight gain. 

• Weeks 9 to 13. If you do gain any weight in your first trimester, it’s likely to occur during these weeks as your morning sickness and other digestive issues may start to subside. 

  • Your breasts continue to get bigger due to growing milk-producing glands, so they may feel fuller or heavier. 

  • It’s possible to have gained up to five pounds, thanks to your growing breasts, placenta, and uterus, plus an increased volume of amniotic fluid and blood.

Pregnancy Weight Gain: Second Trimester

Your second trimester, which typically includes weeks 14 to 27, is when you might begin to see that gradual weight gain. So, how much weight is normal to gain in the second trimester? During this period, you could be adding half a pound and then a pound of weight a week. As mentioned above, talk to your healthcare provider about whether you should start increasing your daily calorie intake. 

• Weeks 14 to 17. You may start to gain half a pound a week, up to two or three pounds in total. It’s not unusual to see more weight gain one week compared to another.  

• Weeks 18 to 22. During these weeks, it’s possible to see up to one pound of pregnancy weight gain per week (or up to four pounds in total). In particular, you might notice your breasts have grown one or two cup sizes. A common question from pregnant people is, “How much weight should you gain by 20 weeks?” By the end of week 20 of your pregnancy, you might see up to 10 extra pounds on the scale, or more!

• Weeks 23 to 27. Your baby’s development is starting to impact your weight gain, as your little one will probably hit the one-pound mark by 24 weeks! Though you may gain about four pounds in total during this period, what you put on each week may vary. You may continue to add about one pound on average.

Pregnancy Weight Gain: Third Trimester

The third trimester typically consists of weeks 28 to 40 and beyond. At this point in your pregnancy, your weight gain may start to look fairly consistent at about one pound per week. So, how much weight do you gain in the last trimester of pregnancy? It’s possible to gain an extra 12 pounds or so, but keep in mind that healthy weight gain is different for each person. 

• Weeks 28 to 31. As you settle into your third trimester, you might start gaining weight more consistently—at a rate of about one pound each week. 

  • This weight probably won’t include fat, though. Instead, weight gain in these weeks of pregnancy is usually from your developing baby, growing placenta, and increased fluids (amniotic and body tissue fluids).

  • Weight gain could also cause aches and pain or other sensations, like tingling, numbness, or swelling in your joints, wrists, and hands. These symptoms typically subside once you deliver your baby and lose your pregnancy weight.

• Weeks 32 to 35. You’re in the home stretch of your pregnancy, and you may gain about a pound a week. You don’t want to gain too much during these final weeks, especially if you had a higher pre-pregnancy BMI. Continue to work with your healthcare provider and keep an eye on your weight.

• Weeks 36 to 40. During your final weeks of pregnancy, your baby is nearly fully developed. This means that you might not notice as much weight gain or even gain any at all. In fact, you may even lose a pound or two during this time!

To help you visualize your pregnancy weight gain week by week, we’ve included a general breakdown of trimester weeks in the chart below. Of course, any weight gain during pregnancy is related to your pre-pregnancy BMI and individual situation. For example, if you’re experiencing a twin pregnancy, you can expect to gain more weight. The chart below provides estimates for people with a normal pre-pregnancy BMI and expecting one baby.

Pregnancy Weight Gain Tracker

To make sure you’re gaining an appropriate amount of weight, as advised by your healthcare provider, it may help to use a pregnancy weight gain calculator and tracker. Check out our simple steps and tools below to help you stay on track:

1. You can start with our Pregnancy Weight Gain Calculator to find the ideal weight gain range for your unique pregnancy. 

2. Then, after talking to your provider, track your pregnancy weight gain week by week. This will help you understand if you’re on the right path, gaining too much or too little. 

3. Download our pregnancy weight gain tracker to help you along the way!

4. To know what to anticipate as your pregnancy progresses, including body changes and baby development, check out our pregnancy calendar.

When Do You Start Gaining Weight in Pregnancy?

increase in weight during the second and third trimesters. Weight gain typically starts in the first trimester, but it's usually minimal—only about 1 to 4.5 pounds (0.5 to 2 kg).

The most noticeable weight increase in pregnancy often begins around week 20, as your baby—and your body—start growing more rapidly. This is when you may notice that you’re gaining weight more steadily each week, especially as the baby, placenta, amniotic fluid, and maternal fat stores all contribute to the number on the scale.

When Do You Gain the Most Weight in Pregnancy?

If you're wondering, “When in pregnancy do you gain the most weight?” it's usually during the second half, with the third trimester seeing the highest rate of weight gain per week. This steady weight gain while pregnant supports your baby's growth and prepares your body for labor, delivery, and breastfeeding. If you haven’t already, check out our Pregnancy Weight Gain by Week section for a more detailed insight.

Keep in mind that maternity weight gain varies for everyone, and your healthcare provider can help ensure your weight gain during pregnancy is healthy and on track for your individual needs.

Where Do You Gain Weight During Pregnancy?

Not all of the weight you gain during pregnancy is body fat around your tummy. It's useful to remember that the average newborn weighs between seven to eight pounds, which is a significant part of the total weight gain during pregnancy and contributes to your baby bump. If you’re also wondering, “How much does a placenta weigh?” “How much does amniotic fluid weigh?” and/or “How much does a uterus weigh in pounds?” Keep reading for an idea.

Here's a pregnancy weight gain breakdown:

• Growing uterus (2 pounds) 

• Placenta (1.5 pounds) 

• Amniotic fluid (2 pounds) 

• Growing breasts (1 to 3 pounds)

• Increased blood volume (3 to 4 pounds)

• Increased fluid volume (2 to 3 pounds) 

• Extra stores of fat, protein, and other nutrients (6 to 8 pounds).

Of course, fat stores contribute to normal weight gain during pregnancy, and they play an important role. In your first trimester, you may notice some added fat in your lower abdomen, accumulating to protect and support your developing baby. After delivery, you’ll need those extra fat stores to fuel breast milk production. For the most part, however, you’ll gradually lose much of your pregnancy weight gain after your baby is born.

Recommendations for Healthy Weight Gain During Pregnancy

It’s not easy to depict appropriate pregnancy weight gain in a chart or graph because everyone is different. Your pre-pregnancy BMI will impact how much weight you’re advised to gain, as will other factors. Here are some general tips for maintaining a healthy weight while gaining those necessary and inevitable pounds during pregnancy. 

• Enjoy a healthy, varied diet. Maintaining a balanced diet during pregnancy is important to your health and the health of your baby. Include healthy carbohydrates, fats, and proteins in your daily diet, focusing on foods that offer a range of vitamins and minerals. Essential nutrients for your pregnancy include vitamins A, B, C, and D, plus calcium and iron, and, of course, folic acid. 

• Plan meals. When you're dealing with cravings, aches and pains, or morning sickness, it can be extra challenging to prepare healthy choices on the spot. Instead, spend some time planning and preparing meals and snacks ahead of time. Ask your partner, family, or friends to help!

• Add calories little by little. Wondering how to gain weight while pregnant? If extra calories are needed, you can support gradual weight gain by increasing your calories slowly. If you’re having a single baby and start your pregnancy with a normal BMI, you may add about 340 daily calories during your second trimester. Then, add about 450 calories a day during your third trimester. Talk with your healthcare provider if you have any questions, are having multiples, or you started pregnancy with a low or high BMI. 

• Listen to your body. There’s no need to force yourself to exceed your calorie intake if you’re not hungry. Instead, listen to your body, follow a healthy pregnancy nutrition plan, and discuss your calorie needs with your healthcare provider if you’re still unsure. 

• Get moving and stay active. Exercise may be the last thing you want to do while pregnant, but it can help you maintain an appropriate weight and support gradual weight gain. Plus, any type of exercise, even walking or running while pregnant, can help ease aches and pain, prepare your body for labor, and increase energy and mood! As a bonus, exercising now might make losing weight postpartum a little bit easier. 

• Don’t actively try to lose weight. Dieting while pregnant isn’t generally healthy, but still, be mindful of the foods you consume. Try to include lots of nutritious, healthy food rather than falling victim to the “eating for two” mentality that may lead to unhealthy food choices. 

• Talk to your healthcare provider. If you’re overweight or underweight, your healthcare provider can offer advice on proper nutrition and other ways to keep you and your baby healthy throughout your pregnancy. Your provider will consider your unique body and situation before advising how much weight you should gain during pregnancy.

The Bottom Line

Although gaining weight during pregnancy is normal, healthy, and expected, it’s not always the easiest thing—emotionally or physically—to navigate. We hope you'll find it more manageable with the help of this guide and our pregnancy weight gain chart and tracker. A few key takeaways include the following:

• Everyone is different. Pregnancy weight gain guides are general since each pregnancy is unique. Use our resources as a foundation, but consult your healthcare provider for personalized weight goals.

• Weight gain should be gradual. Your pregnancy weight gain should be gradual and consistent. If it isn’t, consult your healthcare provider. Focus on your overall pregnancy rather than individual gains. 

• Consider your BMI. While BMI isn't the best health indicator, it's useful for guiding ideal pregnancy weight gain. Those with a lower pre-pregnancy BMI may need to gain more weight, while those with a higher BMI may need to gain less.

• Enjoy a varied diet and light exercise. Help maintain a healthy pregnancy weight with a balanced diet and light exercise. 

• Speak with your healthcare provider. Pregnancy is a long journey, and your healthcare provider is your best source of support, advice, and guidance for your unique situation. 

And remember, once your little one is born, you’ll likely start to lose that baby weight and enjoy time with your sweet newborn! All those cuddles, baby sounds, and diaper changes will quickly distract you. Download the Pampers Rewards app as you prepare to stock your nursery, earning Pampers Cash after purchasing all those newborn baby essentials.

_{How We Wrote This Article The information in this article is based on the expert advice found in trusted medical and government sources, such as the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists. You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.}