Nutrition and weight gain for multiple pregnancy

Good nutrition and a healthy weight gain help your multiple fetuses grow well before birth and do well after birth. Of course, you also benefit by having the most possible energy for carrying your pregnancy, giving birth, and taking care of your newborns.

How much weight gain is healthy for you depends on your body mass index (BMI) at the time that you became pregnant. (Body mass index compares weight to height. The lower your body mass index is, the less body fat you have.) If you have a lower BMI, it is best to gain more weight during pregnancy than if you have a higher BMI.

Recommended weight gain during twin pregnancy ¹

	By 20 weeks	By 28 weeks	By 38 weeks
Underweight (BMI less than 19.8)	25lb to 35lb	37lb to 51lb	50lb to 64lb
Healthy weight (BMI 19.8–26)	20lb to 30lb	30lb to 46lb	40lb to 56lb
Overweight (BMI 26.1–29)	20lb to 25lb	28lb to 37lb	38lb to 47lb
Obese (BMI more than 29)	15lb to 20lb	25lb to 28lb	33lb to 36lb

Expected weight gain increases with each additional fetus.

Pregnancy increases your need for energy from food, called calories. This calorie need is greater with each fetus you are carrying. (Be sure that most of what you eat gives you quality calories, rather than empty calories, such as those found in junk food.) For example, the average woman needs 2,200 calories per day and 2,500 when she is pregnant. For twins, her need increases to 3,500 calories, and for triplets or more, she needs 4,500 calories.

Talk to your health professional or a dietitian about your daily calorie needs, because your needs depend on your height, weight, and activity level. For more information about nutritious calorie choices, see the topic Healthy Eating.

Your health professional may give you a nutrition plan to follow throughout pregnancy and while breast-feeding. You may also receive a prescription for a vitamin and mineral supplement or a list of recommended nonprescription supplements.

Check out the federal Women, Infants, and Children (WIC) nutritional program for helpful information (www.fns.usda.gov/wic). If your resources are limited, you may qualify for WIC financial assistance for basic healthy foods during and after your pregnancy.

Folic acid

Folic acid is a B vitamin. Taking folic acid before and during pregnancy reduces the chance of having a baby with a neural tube defect or other birth defects.

• All women of childbearing age should take daily supplements containing 0.4 milligrams (400 micrograms) of folic acid.² This amount is found in most once-a-day multivitamins.
• Women who are pregnant with twins or more should take 1 mg (1000 mcg) of folic acid daily.³ Folic acid is available in this strength by prescription only.
• Women who have a family history of neural tube defects or who have had a baby with a neural tube defect should take additional folic acid. A daily dosage of 4 mg (4000 mcg) of folic acid is recommended.²

Iron

A typical pregnancy doubles a woman's iron requirements during the second and third trimesters. This extra iron supports the extra blood in your system and helps with fetal and placental growth. When carrying more than one fetus, you need even more iron, both for your fetuses and for you, because multiple pregnancy increases your risk of heavy bleeding during childbirth.

Women with multiple pregnancy are advised to take 60mg to 100mg of iron daily.² You may wait until your second trimester to start taking iron. Your iron requirements are slight during the first trimester of pregnancy, and taking iron supplements in the first trimester may aggravate morning sickness and constipation. Taking your iron at bedtime may decrease the chance of stomach upset.

Calcium

Calcium is needed for the development of the fetal skeleton. You can get enough calcium in your diet by eating or drinking 4 servings from the dairy (milk) group each day. Good sources of calcium from nonmilk sources include:

• Greens (such as mustard and turnip greens), bok choy, kale, and watercress.
• Broccoli and cauliflower.
• Tofu that is "calcium-set."
• Corn tortillas made with lime.
• Calcium-fortified orange juice.

Citations

1. Newman RB (2003). Multiple gestation. In JR Scott et al., eds., Danforth's Obstetrics and Gynecology, 9th ed., pp. 225–245. Philadelphia: Lippincott Williams and Wilkins.

2. Cunningham FG, et al. (2005). Prenatal care. In Williams Obstetrics, 22nd ed., pp. 201–229. New York: McGraw-Hill.

3. Cunningham FG, et al. (2005). Multifetal gestation. In Williams Obstetrics, 22nd ed., pp. 911–948. New York: McGraw-Hill.