Calorie Needs During Pregnancy: A Complete Guide
How many extra calories do you need during pregnancy?
Most women need no significant extra calories in the first trimester, approximately 340 additional calories per day in the second trimester, and approximately 450 additional calories per day in the third trimester, above their pre-pregnancy maintenance intake. These are averages and vary based on your starting weight, activity level, and whether you are carrying multiples. Use the calculator below for a trimester-specific estimate.
Table of Contents
What Nutrients Are Most Important to Track During Pregnancy?
How Do You Track Pregnancy Nutrition Without Obsessing Over Numbers?
Pregnancy Calorie Calculator
Pregnancy Calorie Calculator
Why Do Calorie Needs Change Across Each Trimester?
Pregnancy is not a static nutritional state. The energy demands on your body change substantially across the three trimesters as foetal development progresses and your body composition shifts.
In the first trimester, the foetus is very small and the direct caloric cost of its growth is minimal. The ACOG and most major nutrition bodies recommend no significant increase in calories above pre-pregnancy maintenance for most women in the first trimester. This is also the period most commonly affected by morning sickness and food aversions, which often reduce appetite anyway. The focus in the first trimester is nutrient quality, particularly folate for neural tube development, rather than calorie quantity.
In the second trimester, foetal growth accelerates significantly and the placenta has fully formed. Your blood volume has increased substantially, your basal metabolic rate is rising, and your body is building the fat reserves that support late pregnancy and breastfeeding. The additional 340 calories per day recommended by the ACOG for this period reflects these increased demands.
In the third trimester, the foetus is gaining weight rapidly, up to 200 to 250 grams per week in the final weeks, and your total body mass has increased substantially. Energy expenditure is higher simply because your body is larger and carrying more weight. The additional 450 calories per day recommended in this period reflects both the direct caloric cost of foetal growth and the higher metabolic demands of your increased body mass.
What Nutrients Are Most Important to Track During Pregnancy?
Calories are the foundation, but pregnancy nutrition is not just about eating enough. Specific micronutrients become critical at different points in foetal development, and deficiencies in these can have consequences that persist beyond the pregnancy itself.
Folate is critical in the first four weeks after conception, often before a pregnancy is confirmed, for neural tube formation. The recommended intake rises from 400 mcg pre-pregnancy to 600 mcg during pregnancy. Leafy greens, beans, and fortified cereals are dietary sources, but a prenatal supplement that includes methylfolate is recommended for most women.
Iron needs increase substantially during pregnancy because your blood volume increases by approximately 50 percent to supply the placenta and foetus. The requirement rises from 18 mg per day to 27 mg per day. Many women become mildly anaemic during pregnancy, which is why iron monitoring is a standard part of prenatal care.
Calcium remains at 1,000 mg per day during pregnancy for most adults, the same as pre-pregnancy, but the consequence of inadequate intake shifts. If dietary calcium is insufficient, the foetus draws calcium from maternal bone stores, which can affect long-term maternal bone density.
Choline, which supports foetal brain and memory development, is often overlooked in standard prenatal vitamins. The recommendation increases to 450 mg per day during pregnancy. Eggs are one of the richest dietary sources, making them a particularly useful food for pregnant women.
Using Welling's food tracker to log meals during pregnancy surfaces these nutrient levels alongside calories and macros, so gaps can be identified before they become deficiencies.
How Does Pre-Pregnancy Weight Affect Calorie Needs?
Pre-pregnancy BMI significantly affects recommended gestational weight gain targets, which in turn affect how calorie intake should be managed throughout pregnancy.
Women who were underweight before pregnancy, with a BMI below 18.5, are typically advised to gain more weight during pregnancy, in the range of 12.5 to 18 kg, and may benefit from a slightly higher calorie addition above the standard ACOG recommendations.
Women who were at a healthy weight before pregnancy are advised to gain 11.5 to 16 kg and can use the standard trimester-specific additions from the calculator above.
Women who were overweight or obese before pregnancy are typically advised to gain less, 7 to 11.5 kg and 5 to 9 kg respectively, and may not need the full additional calorie recommendations for each trimester. This does not mean restricting calories during pregnancy but rather gaining weight more gradually.
The calculator above uses your pre-pregnancy weight, not your current pregnancy weight, to estimate baseline TDEE, which is the appropriate input for calculating additional calorie needs during pregnancy.
Is Calorie Tracking Safe During Pregnancy?
Yes, when used to ensure adequate intake rather than to restrict it. Calorie tracking during pregnancy serves a different purpose than tracking for weight loss. The goal is to confirm you are eating enough of the right foods, not to create a deficit.
The risk of under-eating during pregnancy is more significant than the risk of over-eating within the recommended ranges. Inadequate caloric intake during pregnancy is associated with foetal growth restriction, preterm birth, and low birth weight. The calculator in this guide intentionally adds the appropriate calorie amount rather than subtracting it.
If you have a history of disordered eating, discuss tracking with your healthcare provider before starting. For most pregnant women, using an app like Welling to build awareness of nutrient intake, particularly for folate, iron, calcium, and choline, is a useful tool for supporting a healthy pregnancy.
How Do You Track Pregnancy Nutrition Without Obsessing Over Numbers?
The most practical approach during pregnancy is to focus on nutrient-dense whole foods rather than hitting precise calorie numbers every day. Pregnancy appetite naturally fluctuates, and on days with morning sickness or food aversions, flexibility matters more than precision.
Use the calculator above to understand your approximate daily calorie range for your current trimester. Use Welling's food tracker to spot patterns: are you consistently getting enough protein, iron, and calcium? Are there days where intake is very low because of nausea? The AI nutrition coach in Welling can answer specific pregnancy nutrition questions, such as which foods are highest in choline or how to get more iron without eating red meat every day.
The goal is awareness and nutritional completeness, not perfection. Confirming your specific calorie and weight gain targets with your midwife or OB-GYN gives you clinical guidance that accounts for your individual pregnancy circumstances.
Track your pregnancy nutrition in seconds, not minutes.
Welling logs meals from a photo, chat, or voice note in 2.6 seconds on average and surfaces key pregnancy nutrients including folate, iron, and calcium alongside your daily calorie total.
Frequently Asked Questions
How many extra calories do I need during pregnancy?
Per ACOG guidelines, most women need no significant additional calories in the first trimester, approximately 340 additional calories per day in the second trimester, and approximately 450 additional calories per day in the third trimester, above their pre-pregnancy maintenance intake. Individual needs vary based on starting weight, activity level, and whether you are carrying multiples.
Should I track calories during pregnancy?
Calorie tracking during pregnancy can be useful for ensuring you are eating enough, not for restricting intake. It is particularly helpful for monitoring key nutrients like folate, iron, calcium, and choline that require specific attention during pregnancy. If you have a history of disordered eating, discuss this with your healthcare provider.
What happens if I do not eat enough calories during pregnancy?
Inadequate caloric intake during pregnancy is associated with foetal growth restriction, low birth weight, and preterm birth. The body will prioritise foetal development over maternal nutritional stores to some extent, but severe or prolonged restriction has documented negative consequences for pregnancy outcomes. Eating enough is more important than eating precisely during pregnancy.
Is it safe to use a calorie tracking app during pregnancy?
Yes, when the app is used to ensure nutritional adequacy rather than to restrict calories. Welling's food tracker tracks folate, iron, calcium, and other pregnancy-relevant nutrients alongside calories, which makes it a useful tool for pregnancy nutrition monitoring. Always confirm your specific goals with your midwife or OB-GYN.
How much weight should I gain during pregnancy?
ACOG guidelines recommend different weight gain ranges based on pre-pregnancy BMI: 12.5 to 18 kg for underweight women, 11.5 to 16 kg for healthy weight women, 7 to 11.5 kg for overweight women, and 5 to 9 kg for obese women. Your midwife or OB-GYN will monitor your weight gain throughout and give personalised guidance.
What are the most important foods to eat during pregnancy?
Leafy greens for folate, lean meat and lentils for iron, dairy or fortified plant milks for calcium, eggs for choline, and fatty fish or algae-based omega-3 supplements for DHA are the highest priority food categories for pregnancy nutrition. A high-quality prenatal vitamin covers most micronutrient gaps, but dietary sources matter alongside supplementation.
References
American College of Obstetricians and Gynecologists. (2023). Nutrition During Pregnancy. ACOG FAQ. https://www.acog.org/womens-health/faqs/nutrition-during-pregnancy
Institute of Medicine (US). (2009). Weight Gain During Pregnancy: Reexamining the Guidelines. National Academies Press. https://www.ncbi.nlm.nih.gov/books/NBK32813/
National Institutes of Health Office of Dietary Supplements. (2024). Folate Fact Sheet for Consumers. https://ods.od.nih.gov/factsheets/Folate-Consumer/
National Institutes of Health Office of Dietary Supplements. (2024). Iron Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/
Zeisel, S. H. (2006). Choline: Critical Role During Fetal Development and Dietary Requirements in Adults. Annual Review of Nutrition, 26, 229-250. https://pubmed.ncbi.nlm.nih.gov/16848706/
Koletzko, B., et al. (2019). Nutrition During Pregnancy, Lactation and Early Childhood. Annals of Nutrition and Metabolism, 74(2), 93-106. https://www.karger.com/Article/Abstract/496965
