Your meal plan for diabetes needs to be modified when you are pregnant. The total calories you need are based on your prepregnancy weight, age, activity level, and whether you are carrying more than one baby. Your calorie needs:

• Remain the same during the first trimester (weeks 1 through 12) as they were before pregnancy. But you may need extra calories if you have nausea, vomiting, or a low blood sugar level.
• Increase during the second and third trimesters (week 13 through 40). During this time, you need 300 calories a day more than your prepregnancy intake.

If you are at a healthy weight before you get pregnant (BMI between 18.5 and 24.9), aim for a total weight gain of 25 lb (11.3 kg) to 35 lb (15.9 kg), with a rate of weight gain of about 1 lb (0.5 kg) each week during the second and third trimester.

• Excessive weight gain [greater than 6.5 lb (3 kg) a month for a woman who was of normal weight or overweight at conception] can contribute to insulin resistance.
• Inadequate weight gain [less than 0.5 lb (0.2 kg) a week or less than 2 lb (0.9 kg) a month] may mean that you and your baby are not getting enough nourishment.

Dieting to lose weight during pregnancy is not recommended, because you may not receive enough nourishment for you and your baby, and it may increase your risk for premature delivery.

Follow these guidelines for your meal plan during pregnancy.

Carbohydrate

About 40% to 50% of your calories should come from carbohydrate foods, and these should be spread throughout the day. Inadequate carbohydrate intake can result in low blood sugar (hypoglycemia) for women taking insulin and in ketone production for women who have gestational diabetes. Excessive carbohydrate intake can result in elevated blood sugar levels.

Your snacks should include less carbohydrate than at meals. And your breakfast should be no more than 10 hours after your bedtime snack. This helps prevent low blood sugar (hypoglycemia) in women who take insulin and ketone production in women who have gestational diabetes.

Make sure your meal plan contains:

• Complex carbohydrate, especially foods high in fiber, such as oatmeal, brown rice, bran cereal, whole wheat bread, whole wheat pasta, and beans.
• Fresh fruits.
• Milk.
• Fresh or frozen vegetables.

Limit these carbohydrate foods in your diet:

• Refined sugar and foods with a high content of refined sugars (sweets)
• Refined starches, such as highly processed breakfast cereals, instant potatoes, instant rice, or instant noodles
• Fruit juice

Protein

About 20% to 25% of your daily calories should come from protein foods. If your kidney function is impaired, your protein allowance may be lower.

Fat

About 30% of your calories should come from fat. Monounsaturated fats and omega-3 fats, rather than saturated fats, should continue to be the primary source of fat in your diet. Less than 10% of your daily calories should come from saturated fats and your cholesterol intake should be less than 300 mg each day.

Fiber

Get enough fiber each day. Fiber can help stabilize your blood sugar levels and relieve constipation, which is common during pregnancy.

Most people get far more sodium than they need. Talk to your doctor about how much sodium you should eat.

Vitamins and minerals

Take a prenatal vitamin with folic acid and iron to meet your body's increased need for these micronutrients. Folic acid is needed for the production of blood cells. And iron is needed for red blood cells to deliver oxygen throughout the body. Folic acid has also been proved to reduce the risk of fetal neural tube defects. You need to get 0.4 mg (400 mcg) of folic acid each day.

You may need to take a vitamin B12 supplement, which is important for the production of red blood cells, and a vitamin D supplement if you are a strict vegetarian (vegan). Vitamin B12 can only be obtained from animal sources in the diet.

Other vitamins and minerals, such as the B vitamins and calcium, are important during pregnancy for producing energy and preserving your body's calcium stores.

Very large doses (megadoses) of vitamins, especially vitamins A and D, are not recommended during pregnancy. Vitamins and minerals should only be taken under your doctor's supervision.

Artificial sweeteners

Saccharin (Sweet'N Low, Sugar Twin), aspartame (Equal, NutraSweet), acesulfame K (Sunett), sucralose (Splenda), and neotame are safe to eat when you are pregnant.

Avoid using aspartame (Equal or Nutrasweet) if you have phenylketonuria (PKU).

Caffeine

Avoid caffeine, or limit your intake to about 1 cup of coffee or tea each day.

Alcohol

Do not drink alcohol. No amount of alcohol has been proved to be safe for a developing baby (fetus).

Herbs

Some herbs may cause premature labor and others may cause high or low blood sugar levels. Talk with your doctor if you are taking any herbs.