Do You Burn More Calories During Pregnancy? What You Need to Know

Pregnancy brings many changes to your body, and one of the questions many women have is: Do you burn more calories during pregnancy? Weight fluctuations are common during this time, with some women losing weight due to morning sickness early on, and gaining weight as the pregnancy progresses. Understanding how calorie consumption, weight gain, and healthy eating play a role during pregnancy is important for both your health and the health of your baby.

We spoke with Dr. Michael Rosenbaum, a professor of pediatrics and medicine at Columbia University Medical Center, to help answer the burning question: Do you burn more calories during pregnancy?

Do You Burn More Calories During Pregnancy?

Yes, pregnant women do burn more calories during pregnancy. According to Dr. Michael Rosenbaum, “Whether it’s resting energy expenditure, total energy expenditure, or calories burned through physical activity, calories will increase, especially during the second and third trimesters.”

He further explains that the increase in calorie burn varies from woman to woman. “How much weight a person gains during pregnancy depends on the balance between the calories consumed and the calories burned, as well as how much of the weight gained is water,” he adds.

Interestingly, it’s not just the mother burning extra calories. Dr. Rosenbaum emphasizes that when we talk about calorie consumption, it’s important to consider the energy expenditure of both the mother and the baby (the maternal-fetal unit). “The fetus burns calories at about four times the rate of the mother, and as the baby grows, this becomes a larger factor in determining energy consumption,” he explains.

Does Your Metabolism Speed Up During Pregnancy?

Yes, metabolism does increase, particularly during the second and third trimesters. However, Dr. Rosenbaum clarifies that the increase is due to resting energy expenditure, not necessarily due to physical activity like walking or exercise. “This is primarily due to weight gain, but not entirely, and it’s also influenced by the mother’s pre-pregnancy weight,” he explains.

For women who were not overweight before pregnancy, daily energy expenditure or calorie intake increases by about 110 calories. For women who were overweight before pregnancy, the increase is closer to 45 calories per day. This highlights the variability between individuals.

How Many Calories Do You Burn During Pregnancy?

To provide some numbers, Dr. Rosenbaum references a 2021 study that investigated how many calories pregnant women burn during each trimester. During the early pregnancy phase, 24-hour energy expenditure or calories burned is about 144 calories per day. In the second trimester, this number increases to 170 calories per day, and by the third trimester, it’s around 290 calories per day. Most of the calories burned are due to resting energy expenditure.

Frequently Asked Questions

Which Types of Foods Help Support Energy Expenditure During Pregnancy?

Dr. Rosenbaum states that the dietary recommendations are the same, whether pregnant or not. The American Institute of Medicine suggests that about 45% to 65% of your diet should come from carbohydrates, 10% to 35% from proteins, and 20% to 35% from healthy fats, while limiting saturated and trans fats to support both your body and the growing baby. “There’s no indication that the specific macronutrient composition or the types of foods you eat themselves will affect energy expenditure during pregnancy,” he says.

Will You Burn Fat During Pregnancy?

Yes, you will burn fat during pregnancy, but you will also burn carbohydrates and a small amount of protein, depending on your diet and certain medical conditions that may affect your fat absorption or utilization. Dr. Rosenbaum advises against attempting to lose weight during pregnancy unless under close medical supervision. If you are at risk for conditions such as gestational diabetes, hypertension, or preeclampsia, it’s important to consult with a healthcare provider.

How Much Weight Gain Is Healthy During Pregnancy?

Dr. Rosenbaum explains that healthy weight gain depends on the mother’s body fat levels. “The more obese the mother is, the less weight she should gain during pregnancy, as long as the weight gained is enough to ‘nourish the baby,’” he states. According to the Institute of Medicine, the recommended weight gain based on body mass index (BMI) is as follows:

Pre-pregnancy BMI (kg/m²)

Recommended Weight Gain (lbs)

Weight Gain per Week in 2nd & 3rd Trimester

Underweight (<18.5)

28-40 lbs

1-1.3 lbs

Healthy Weight (18.5-24.9)

25-35 lbs

0.8-1 lb

Overweight (25-29.9)

15-25 lbs

0.5-0.7 lb

Obese (≥30)

11-20 lbs

0.4-0.6 lb

However, Dr. Rosenbaum emphasizes that BMI doesn’t account for your fat-to-muscle ratio, fat distribution, or overall health. Healthy pregnancy weight gain can vary for different body types. Throughout pregnancy, your healthcare provider should closely monitor your weight and alert you to any concerning weight loss or gain.

Conclusion

Pregnancy does lead to an increase in calorie consumption, primarily due to weight gain and fetal development. However, the amount of weight you should gain and how much energy your body burns depends on various factors, including your pre-pregnancy weight and overall health. It’s important to follow a healthy diet, gain weight within recommended guidelines, and consult with your healthcare provider to ensure the best outcome for both you and your baby.

By understanding how pregnancy affects calorie burn and weight gain, you can better navigate the many changes that come with this special time in your life.