Prenatal care - managing your weight

Most women should gain somewhere between 25 and 35 pounds (11.5 to 16 kilograms) during pregnancy. Most will gain 2 to 4 pounds (1 to 2 kilograms) during the first trimester, and then 1 pound (0.5 kilogram) a week for the rest of the pregnancy. The amount of weight gain depends on your situation.

• Overweight women need to gain less (10 to 25 pounds or 4 to 11 kilograms or less, depending on their pre-pregnancy weight).
• Underweight women will need to gain more (28 to 40 pounds or 13 to 18 kilograms).
• You should gain more weight if you are having more than 1 baby. Women having twins need to gain 37 to 54 pounds (16.5 to 24.5 kilograms).

A balanced, nutrient-rich diet, along with exercise, is the basis for a healthy pregnancy. For most pregnant women, the right amount of calories is:

• 1,800 calories per day in the 1st trimester
• 2,200 calories per day in the 2nd trimester
• 2,400 calories per day in the 3rd trimester

Much of the weight that you gain during pregnancy is not fat, but is related to the baby. Here is a breakdown of how 35 pounds (16 kilograms) adds up:

• Baby: 8 pounds (3.5 kilograms)
• Placenta: 2 to 3 pounds (1 to 1.5 kilograms)
• Amniotic fluid: 2 to 3 pounds (1 to 1.5 kilograms)
• Breast tissue: 2 to 3 pounds (1 to 1.5 kilograms)
• Blood supply: 4 pounds (2 kilograms)
• Fat stores: 5 to 9 pounds (2.5 to 4 kilograms)
• Uterus growth: 2 to 5 pounds (1 to 2.5 kilograms)

Some women are already overweight when they get pregnant. Other women gain weight too quickly during their pregnancy. Either way, a pregnant woman should not go on a diet or try to lose weight during pregnancy.

It is better to focus on eating the right foods and staying active. If you do not gain enough weight during pregnancy, you and your baby may have problems.

Still, you can make changes in your diet to get the nutrients you need without gaining too much weight. Talk to your health care provider to get help with planning a healthy diet.

Below are some healthy eating tips to help you get started.

Healthy choices:

• Fresh fruits and vegetables make good snacks. They are full of vitamins and low in calories and fat.
• Eat breads, crackers, and cereals made with whole grains.
• Choose reduced-fat dairy products. You need at least 4 servings of milk products every day. However, using skim, 1%, or 2% milk will greatly reduce the amount of calories and fat you eat. Also choose low-fat or fat-free cheese or yogurt.

Foods to avoid:

• Naturally sweetened is better than foods and drinks with added sugar or artificial sweeteners.
• Food and drinks that list sugar or corn syrup as one of the first ingredients are not good choices.
• Many sweetened drinks are high in calories. Read the label and watch out for drinks that are high in sugar. Substitute water for sodas and fruit drinks.
• Avoid junk-food snacks, such as chips, candy, cake, cookies, and ice cream. The best way to keep from eating junk food or other unhealthy snacks is to not have these foods in your house.
• Go light on fats. Fats include cooking oils, margarine, butter, gravy, sauces, mayonnaise, regular salad dressings, lard, sour cream, and cream cheese. Try the lower-fat versions of these foods.

Eating out:

• Knowing the amount of calories, fat, and salt in your food can help you eat healthier.
• Most restaurants have menus and nutrition facts on their websites. Use these to plan ahead.
• In general, eat at places that offer salads, soups, and vegetables.
• Avoid fast food.

Cooking at home:

• Prepare meals using low-fat cooking methods.
• Avoid fried foods. Frying foods in oil or butter will increase the calories and fat of the meal.
• Baking, broiling, grilling, and boiling are healthier, lower-fat methods of cooking.

Exercise:

• Moderate exercise, as recommended by your provider, can help burn extra calories.
• Walking and swimming are generally safe, effective exercises for pregnant women.
• Be sure to talk to your provider before starting an exercise program.

If you have struggled with your weight in the past, it may be hard to accept that it is OK to gain weight now. It is normal to feel anxious as the numbers on the scale edge up.

Keep in mind that you need to gain weight for a healthy pregnancy. The extra pounds will come off after you have had your baby. However, if you gain a lot more weight than is recommended, your baby will also be bigger. That can sometimes lead to problems with delivery. A healthy diet and regular exercise are your best ways to ensure a healthy pregnancy and baby.

Berger DS, West EH. Nutrition during pregnancy. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 6.

Bodnar LM, Himes KP. Maternal nutrition. In: Lockwood CJ, Copel JA, Dugoff L, et al, eds. Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2023:chap 12.