During Your Pregnancy
Pregnancy and weight gain

Weight Gain During Pregnancy

You need to be careful about how much weight you gain during your pregnancy. Gaining too much or too little can be harmful to you and your baby. How many pounds you need to add depends on how much you weigh when you become pregnant.
You're pregnant, right? So you get to eat as many french fries as you want, right? Wrong! Be careful about how much weight you gain during your pregnancy. Gaining too much or too little can be harmful to you and your baby. How many pounds you need to add depends on how much you weigh when you become pregnant.

Gaining the right amount of weight helps protect the health of your baby. Women who gain too little are at increased risk of having a small baby (less than 5 1/2 pounds). Women who gain too much are at increased risk of having an early baby or a large baby. They may also have health problems themselves such as diabetes, high blood pressure and varicose veins.   

In general, most women need around 300 extra calories per day during pregnancy. (One extra healthy snack, such as four fig bars and a glass of skim milk, will provide these calories.) However, the exact amount of extra calories you need depends on your weight before pregnancy. Talk to your health provider to learn more about a healthy eating plan that’s right for you.  

How Much Weight Should You Gain
Below are some guidelines about weight gain during pregnancy. Talk to your health provider about your specific pregnancy weight gain goals.

If you began pregnancy at a normal weight, you should gain 25–35 pounds over the nine months. Assuming you gain between 1 and about 4 ½ pounds in the first trimester, you should put on about one pound every week in the second and third trimesters  

If you began pregnancy underweight, you should probably gain a little more. That's because underweight women are more likely to have small babies. A 28- to 40-pound gain is usually recommended. Assuming you gain between 1 and about 4 ½ pounds in the first trimester, try to gain slightly over a pound a week in the second and third trimesters.

If you began pregnancy overweight, you should gain only 15–25 pounds over the nine months. Assuming you gain between 1 and about 4 ½ pounds in the first trimester, you should put on slightly over ½ pound every week in the second and third trimesters. While you don't want to gain too much weight, you should never try to lose weight during pregnancy because that could harm your baby.

If you were obese at the start of your pregnancy, you should gain only 11–20 pounds over the nine months. Assuming you gain between 1 and about 4 ½ pounds in the first trimester, aim for gaining slightly under ½ pound every week in the second and third trimesters.

Where does it all go?
Approximate breakdown of a weight gain of 29 pounds
Blood 3 pounds
Breasts 2 pounds
Womb 2 pounds
Baby 7.5 pounds
Placenta 1.5 pounds
Amniotic fluid 2 pounds
Fat, protein & other nutrients 7 pounds
Retained water 4 pounds

If you're expecting twins and began pregnancy at a normal weight, you should probably gain between 37-54 pounds over the nine months. If you began pregnancy overweight, aim for gaining a total of 31-50 pounds. If you were obese at the start of your pregnancy, you should gain between 25-42 pounds over the nine months.  That translates into about 1 ½ pounds a week in the last two trimesters.

To find out if you were underweight or overweight before pregnancy, learn your Body Mass Index (BMI). BMI is a measure of body fat based on height and weight.

Putting on weight slowly and steadily is best. But don't worry if you gain less than four pounds in the first trimester, and make up for it later, or vice versa. Also, many women have one or two "growth spurts" during which they gain several pounds in a short time period, and then level off. Again, this is not worrisome unless it becomes a pattern. The important thing is to keep an eye on your overall gain. You can use the weight-gain tracking chart to follow your progress.

September 2009






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