A weight gain of around 25 pounds during pregnancy is usually considered healthy, but factors like your body mass index entering pregnancy and the number of babies you’re carrying can influence this.

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According to the National Center for Health Statistics, there were 3,664,292 births in the United States in 2021. 8.52% of the babies born were low birthweight, and 10.49% were preterm.

A variety of health concerns can lead to premature and low birthweight babies. However, one way to encourage a full-term, healthy baby is to gain a healthy amount of pregnancy weight.

Weight gain is expected during pregnancy as the baby develops, and there are general recommendations for appropriate amounts of weight gain depending on an individual’s prepregnancy body mass index (BMI). However, it’s also important to speak with your doctor about what appropriate weight gain should look like in your specific pregnancy.

Learn more about healthy nutrition during pregnancy.

According to the American College of Obstetricians and Gynecologists (ACOG), assuming that a pregnant individual has had a weight gain of 1.1–4.4 pounds (lb) in the first trimester, the recommended pregnancy weight gain schedule is:

BMIAverage weekly weight gain in second and third trimestersOverall
Underweightunder 18.51–1.3 lb28–40 lb
Normal weight18.5–24.90.8–1 lb25–35 lb
Overweight25–29.90.6 lb15–25 lb
Obeseover 300.5 lb11–20 lb

If you’re giving birth to multiple babies, a healthy pregnancy will typically require a bit more weight gain.

The Institute of Medicine (IOM) recommends that women of normal weight carrying twins gain 37–54 lb (16.8–24.5 kg) during their pregnancies. Women who are overweight should gain 31–50 lb (14.1–22.7 kg) and women with obesity 25–42 lb (11.3–19.1 kg).

According to the IOM, there’s insufficient data to determine what healthy weight gain is for triplets and other higher level multiple pregnancies.

Much of the extra weight gained during pregnancy goes toward the baby and the protective structures the body creates for the baby.

The weight of the baby and the placenta is typically about 9–10 pounds of the pregnancy weight gain. Amniotic fluid and increased blood volume can account for approximately 6 more pounds. And uterus and breast tissue growth can add 4 or more pounds. This leaves very little weight being stored as fat in healthy pregnancy weight gain.

While it’s generally not recommended to attempt to lose weight during pregnancy, you may find that you unintentionally lose some weight during the first trimester. This can occur as a result of nausea, food aversions, and other first-trimester pregnancy symptoms.

in many cases, your pregnancy weight gain will naturally resolve as your pregnancy continues, but your doctor may recommend different medications and fluid IVs in severe cases to help you avoid dehydration.

ACOG does not recommend weight loss during pregnancy regardless of your BMI prior to or at conception.

What can happen if I gain too much weight during pregnancy?

Gaining too much weight during pregnancy can raise your blood pressure. It can place you at an increased risk of complications like gestational diabetes and preeclampsia.

Is it possible to gain too little weight during pregnancy?

Some individuals can remain slim and have healthy babies, but individuals who don’t gain sufficient weight during their pregnancy may be at an increased risk of having a baby with low birth weight or premature birth.

Do I really need to take prenatal vitamins if I’m pregnant?

The ACOG recommends the use of a daily prenatal vitamin along with a healthy diet to ensure that your body has all the vitamins and minerals it needs during pregnancy.

Healthy pregnancy weight gain can vary depending on an individual’s BMI. It’s important for all individuals to eat a nutritious diet and take prenatal vitamins daily during pregnancy to ensure their body has the proper fuel for growing a baby.

Your doctor can offer advice and help to set your mind at ease if you’re worried about your weight gain during pregnancy.