Healthy lifestyle habits can help you manage pregnancy weight gain and support your baby's health. Also, making smart meal choices during pregnancy can make it easier to shed the extra pounds after you deliver your baby.

There's no one-size-fits-all approach to pregnancy weight gain. Appropriate weight gain during pregnancy depends on various factors, including your pre-pregnancy weight and body mass index (BMI). Your health and your baby's health also play a role. Work with your health care provider to determine what's right for you.

Consider these general guidelines for pregnancy weight gain:

If you're carrying twins or other multiples, you'll likely need to gain more weight. Again, work with your health care provider to determine what's right for you.

Consider these general guidelines for pregnancy weight gain if you're carrying twins:

Being overweight before pregnancy increases the risk of various pregnancy complications, such as gestational diabetes, high blood pressure disorders of pregnancy — including preeclampsia — the need for a C-section and premature birth.

Although a certain amount of pregnancy weight gain is recommended for people who are overweight or obese before pregnancy, some research suggests that people who are obese can safely gain less weight than the guidelines recommend. More research is needed.

Work with your health care provider to determine how much weight you should gain during pregnancy. Your health care provider can offer guidance on nutrition and physical activity and strategies to manage your weight throughout pregnancy.

If you're underweight before pregnancy, it's essential to gain a reasonable amount of weight while you're pregnant. Without the extra weight, your baby might be born early (premature birth) or smaller than expected.

Gaining too much weight during pregnancy can increase your baby's risk of health problems, such as being born significantly larger than average, and complications at birth, such as the baby's shoulder becoming stuck after the head is delivered (shoulder dystocia). Excessive weight gain during pregnancy can also increase your risk of postpartum weight retention.

Let's say your baby weighs in at 7 or 8 pounds (about 3 to 3.6 kilograms). That accounts for some of your pregnancy weight gain. What about the rest? Here's a sample breakdown:

• Larger breasts: 1 to 3 pounds (about 0.5 to 1.4 kilogram)
• Larger uterus: 2 pounds (about 0.9 kilogram)
• Placenta: 1 1/2 pounds (about 0.7 kilogram)
• Amniotic fluid: 2 pounds (about 0.9 kilogram)
• Increased blood volume: 3 to 4 pounds (about 1.4 to 1.8 kilograms)
• Increased fluid volume: 2 to 3 pounds (about 0.9 to 1.4 kilograms)
• Fat stores: 6 to 8 pounds (about 2.7 to 3.6 kilograms)

In the first trimester, most people don't need to gain much weight. This is good news if you're struggling with morning sickness.

If you start out at a healthy weight, you need to gain only about 1 to 4 pounds (0.5 to 1.8 kilograms) in the first few months of pregnancy. You can do this by eating a healthy diet — no extra calories are necessary.

Steady weight gain is more important in the second and third trimesters — especially if you start out at a healthy weight or you're underweight. According to the guidelines, you'll gain about 1 pound (0.5 kilogram) a week until delivery. An extra 300 calories a day — half a sandwich and a glass of skim milk — might be enough to help you meet this goal. For people who are overweight or obese, the guidelines translate to a weight gain of about 1/2 pound (0.2 kilogram) a week in the second and third trimesters. Try adding a glass of low-fat milk or an ounce of cheese and a serving of fresh fruit to your diet.

Your health care provider will keep a close eye on your weight. You can do your part by eating a healthy diet. Also, for most pregnant women, getting at least 30 minutes of moderate-intensity exercise, such as brisk walking or swimming, is recommended on most days. However, talk to your health care provider before starting an exercise program. And be sure to keep your prenatal appointments. To keep your pregnancy weight gain on target, your health care provider might offer suggestions for boosting calories or scaling back as needed.