Is It Safe To Lose Weight While Pregnant?

pregnant woman doing yoga

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During pregnancy, health and wellness take a front seat while your baby develops. It's common to focus more on nutrition, exercise, and self-care while pregnant, to help ensure a safe and healthy pregnancy and delivery.

Weight may be a concern during pregnancy. Some people are worried about not gaining enough weight or gaining too much weight, while others may have started the pregnancy underweight or overweight, and are trying to manage it.

When coping with food aversions, cravings, nausea, and fluctuating hormone levels, weight does change during pregnancy. These ups and downs are noted at doctor visits and are part of the care plan after conception.

It's normal, healthy, and expected to gain weight during pregnancy. According to the American College of Obstetricians and Gynecologists (ACOG), women should gain 11-40 pounds while pregnant. Health experts agree that you should not try weight loss diets while pregnant. Read on to learn more about pregnancy and weight.

Why Losing Weight While Pregnant Is Generally Not Recommended

Risks of Losing Weight While Pregnant

  • Nutrient deficiencies
  • Developmental delays
  • Small fetus for gestational age
  • Increased fatigue

Women who contend with severe nausea or food aversions may unintentionally lose weight during the early months of pregnancy, and these conditions need to be shared with and managed by your health care provider. But purposely trying to lose weight by dieting while pregnant is not advised.

Eating enough during pregnancy ensures both mom and baby will get the nutrients required for overall health. Dieting, cutting calories, or restricting food groups can result in nutrient deficiencies that can affect the developing fetus.

A meta-analysis and systematic review were conducted to examine pregnancy outcomes in obese women with gestational weight loss. The study found that women who tried weight loss diets during pregnancy had had higher odds of delivering babies that were small for gestational age, and the researchers concluded that weight loss diets should not be recommended during pregnancy.

Dr. Julie Rhee is a reproductive endocrinologist and infertility specialist and Director of the Preimplantation Genetic Screening Program at Vios Fertility Institute in St. Louis. Rhee advises a healthy diet and exercise program once you get pregnant, and cautions against weight loss during pregnancy.

"Drastic weight loss would be discouraged in pregnancy, but a healthy diet consisting of exercise and portion control with well-balanced meals can be started during pregnancy."

—Julie Rhee, M.D.

Considering Weight Pre-Pregnancy

If you are trying to conceive, your health care provider may talk to you about losing or gaining weight to promote fertility and reduce pregnancy complications.

While people of all different shapes and sizes can get pregnant, studies show that there is an increased risk of certain complications in people with obesity. These potential complications include a higher risk of preeclampsia, preterm birth, and macrosomia (where the fetus is larger than normal, which can cause injury during birth).

If you are hoping to get pregnant, talk to your health care provider about positive, sustainable lifestyle changes that can support a healthy weight and promote fertility.

Risks of Being Overweight During Pregnancy

According to the ACOG, obesity during pregnancy may put you at risk of several health problems, such as:

  • High blood pressure
  • Preeclampsia (a serious form of gestational high blood pressure)
  • Gestational diabetes
  • Obstructive sleep apnea (a condition where you stop breathing for short periods during sleep)

Your obstetrician will monitor your blood pressure and blood sugar levels during your pregnancy to watch for signs of high blood pressure or gestational diabetes. They may give you specific diet and exercise advice to mitigate these conditions and promote a healthy pregnancy and delivery.

Optimal Weight Gain Recommendations During Pregnancy

When you get pregnant, you will meet with an obstetrician to develop a care plan. During your first visit, you may discuss nutrition and physical activity. You may also discuss your weight since pregnancy weight gain guidelines are often related to your starting weight.

According to the Institute of Medicine (IOM), there are different weight gain recommendations for women of different weights (classified by body-mass index, or BMI). But these are controversial, as BMI is not a reliable indicator of health.

Body Mass Index (BMI) is a dated, biased measure that doesn’t account for several factors, such as body composition, ethnicity, race, gender, and age.

Despite being a flawed measure, BMI is widely used today in the medical community because it is an inexpensive and quick method for analyzing potential health status and outcomes.

Your health care provider may use these standardized IOM recommendations to guide your weight goals during pregnancy. Note that some doctors may not agree with these BMI-based guidelines, and may not follow them.

Current BMI Recommended Weight Gain
(Entire Pregnancy)
Rate of Weight Gain (2nd and 3rd Trimesters)
Less than 18.5 28-40 pounds 1 to 1.3 pounds per week
18.5 to 24.9 25-35 pounds 0.8 to 1 pounds per week
25 to 29.9 15-25 pounds 0.6 pounds per week
30 or more 15-25 pounds 0.5 pounds per week

People of all shapes, sizes, and weights can carry out a healthy pregnancy. The ACOG states that you can have a healthy pregnancy if you are obese, but recommends paying attention to diet, weight, and exercise, and getting regular prenatal care to monitor for complications.

Weight gain below the IOM recommendations among overweight pregnant women does not appear to have a negative effect on the health of the baby. One systematic review suggests that overweight women who gain 6–14 pounds have outcomes as healthy as overweight women who gained weight within the currently recommended guidelines.

For the overweight pregnant woman who is gaining less than the recommended amount but has an appropriately growing fetus, no evidence exists that encouraging increased weight gain to conform with the current IOM guidelines will improve maternal or fetal outcomes.

Tips for Diet and Exercise During Pregnancy

A balanced, nutritious diet and exercise plan are important during pregnancy, since you are caring for both yourself and your baby. Your healthcare team can provide you with the best personalized advice, but here are some tips to get started:

Tips for Healthy Eating

"It is important to eat a balanced diet while pregnant," says Rhee, who adds that watching portion control can be a healthy practice to continue in pregnancy if your weight is a concern.

She also stresses that if you are on medications or supplements to aid weight loss, you should speak to your health care provider to make sure that they are safe during pregnancy. Lastly, Dr. Rhee advises that diets in which one eliminates certain food groups should be avoided.

Deborah Malkoff-Cohen, MS, RD, CDN, CDE says that "eating for two" is an outdated recommendation, especially during the first trimester when the baby is very small. She suggests these tips to create nutritious, balanced meals during pregnancy:

  • Do not skip meals. Eat regularly to make sure you are getting adequate nutrition.
  • Eat lean protein such as chicken and fish. Incorporate fresh meat and seafood into your diet and limit processed meats like bacon, sausage, and hot dogs.
  • Eat mostly whole grains instead of refined grains. Include whole-grain wheat, oats, brown rice, quinoa, or other whole grains into your diet. Limit white, refined grains.
  • Increase your vegetable intake. Fill half of your plate with vegetables at mealtime.
  • Watch your sugar intake. Choose natural sugar, such as fruit, over processed, sugary treats such as candy and ice cream. Pair fruit with a source of protein (such as apple and peanut butter) and try to choose high-fiber fruits such as berries, apples, or pears.
  • Meet with a registered dietitian. A dietitian can help guide you with trustworthy, evidence-based dietary guidance.

Pregnancy Exercise Tips

Physical activity during pregnancy is generally recommended. But what if you have been sedentary? Or what if your weight management program prior to pregnancy included strenuous activity?

Dr. Felice Gersh, M.D. is a board-certified OB/GYN who is also fellowship-trained in integrative medicine. Gersh says that even sedentary women can benefit from initiating an exercise program during pregnancy. "Walking is wonderful!" she says, adding that pregnancy yoga classes or prenatal fitness classes are available to keep women fit while expecting.

Dr. Rhee adds that light to moderate activity is beneficial to pregnant women. "Light jogging, walking, or aerobic exercise at least 30 minutes per day can be beneficial to both mom and baby and also potentially help with labor and postpartum recovery," she says.

Dr. Gersh recommends that you continue the level of exercise you’re comfortable with but don’t push too hard or do high-impact activities. She stresses that you should focus on health—not weight loss—to stay healthy during pregnancy. Dr. Rhee agrees, noting that any exercise is better than none.

A Word From Verywell

Pregnancy is a time to practice self-care by eating well and being physically active. This can help ward off pregnancy complications such as gestational diabetes and high blood pressure and ensure you gain an appropriate amount of weight to support a healthy pregnancy.

It's not a smart idea to try and lose weight while pregnant, since cutting back on food groups or calories can mean your body isn't getting the nutrients that are required for a healthy pregnancy. Speak with a dietitian to plan nutritious meals and snacks during pregnancy.

Frequently Asked Questions

  • Is weight loss during early pregnancy safe?

    Most women gain 2-4 pounds in the first trimester of pregnancy, while others lose weight if they struggle with nausea, morning sickness, or food aversions. These conditions can be managed with help of your health care provider. Purposeful weight loss is not recommended during pregnancy.

  • How much weight should you gain during pregnancy?

    The IOM offers overall weight gain recommendations based on BMI.

    • If your BMI is <18.5, you should gain 28-40 lbs during pregnancy
    • If your BMI is 18.5-24.9 you should gain 25-35 lbs during pregnancy
    • If your BMI is 25-29.9, you should gain 15-25 lbs during pregnancy
    • If your BMI is >30, you should gain 11-20 lbs during pregnancy
  • How many calories do you need in each trimester?

    According to the ACOG:

    • In the first trimester, no extra calories are needed.
    • In the second trimester, you need an extra 340 calories a day.
    • In the third trimester, you need about 450 extra calories a day.
8 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American College of Obstetricians and Gynecologists. How much weight should I gain while pregnant?

  2. Kapadia MZ, Park CK, Beyene J, Giglia L, Maxwell C, McDonald SD. Weight loss instead of weight gain within the guidelines in obese women during pregnancy: a systematic review and meta-analyses of maternal and infant outcomes. PLoS ONE. 2015;10(7). doi:10.1371/journal.pone.0132650

  3. ACOG. Obesity and Pregnancy.

  4. ACOG. Weight Gain During Pregnancy.

  5. Arora P, Tamber aeri B. Gestational Weight Gain among Healthy Pregnant Women from Asia in Comparison with Institute of Medicine (IOM) Guidelines-2009: A Systematic Review. J Pregnancy. 2019;2019:3849596. doi:10.1155/2019/3849596

  6. Lynch MM, Squiers LB, Kosa KM, et al. Making Decisions About Medication Use During Pregnancy: Implications for Communication Strategies. Matern Child Health J. 2018;22(1):92-100. doi:10.1007/s10995-017-2358-0

  7. Mcgee LD, Cignetti CA, Sutton A, Harper L, Dubose C, Gould S. Exercise During Pregnancy: Obstetricians' Beliefs and Recommendations Compared to American Congress of Obstetricians and Gynecologists' 2015 Guidelines. Cureus. 2018;10(8):e3204. doi:10.7759/cureus.3204

  8. Szymanski LM, Satin AJ. Strenuous exercise during pregnancy: is there a limit?. Am J Obstet Gynecol. 2012;207(3):179.e1-6. doi:10.1016/j.ajog.2012.07.021

Additional Reading
  • Weight Gain During Pregnancy. Committee Opinion. American College of Obstetrics and Gynecology. January 2013 (reaffirmed 2018).

  • Obesity and Pregnancy. American College of Obstetrics and Gynecology. April 2016.

  • Moms and Moms-to-Be Health & Nutrition Information. Updated Apr 27, 2018.

  • Deborah Malkoff-Cohen, MS, RD, CDN, CDE. Email Interview. September 2018

  • Felice L. Gersh, M.D. Email Interview. September 2018

  • Julie S. Rhee, MD, FACOG. Email Interview. September 2018

  • Vesco KK, Karanja N, King JC, et al. Efficacy of a group-based dietary intervention for limiting gestational weight gain among obese women: a randomized trial. Obesity (Silver Spring). 2014;22(9):1989-96. DOI: 10.1002/oby.20831.

By Cara Rosenbloom, RD
 Cara Rosenbloom RD is a dietitian, journalist, book author, and the founder of Words to Eat By, a nutrition communications company in Toronto, ON.