How to Prevent Low and Very Low Birth Weight

Birth weight is how much your baby weighs at birth. Your baby will be weighed shortly after he or she is born. Average birth weight is 5.5–9 lb (2.5–4 kg). Low birth weight means that a newborn weighs less than 5.5 lb (2.5 kg). Very low birth weight means that a newborn weighs 3.25 lb (1.5 kg) or less.

There are many reasons why a baby may be born with a low or very low birth weight. The most common causes are being born too early (premature birth), born too small (fetal growth restriction), or both. Your baby may be more likely to have a low birth weight if, during pregnancy, you:

• Smoke.
• Are exposed to secondhand smoke.
• Drink alcohol.
• Do not gain enough weight.
• Have poor nutrition.
• Experience high levels of stress on a regular basis.

Going into labor before your due date (preterm labor) can also result in your baby having a low birth weight.

What are the risks?

The most serious risk of a low or very low birth weight is not surviving the first year of life. This is especially risky for babies born with a very low weight.

Complications shortly after birth may include:

• Infections.
• Heart and lung problems.
• Bleeding in the brain.

Later complications of a low birth weight may include:

• Learning disability.
• Delayed physical development.
• Diabetes.
• Heart disease.
• Obesity.
• High blood pressure, diabetes, and heart disease at the same time (metabolic syndrome).

What can I do to lower my baby’s risk of having a low or very low birth weight?

Medical care

• See your health care provider yearly (annually) for well checks. This many include a physical exam, screening tests, and immunizations.
• If you plan to become pregnant, make an appointment with your health care provider before you become pregnant (preconception care).
• Get good quality medical care on a regular basis during pregnancy (prenatal care). This is important.
• Work with your health care provider to identify and manage any conditions or other risks that could contribute to premature birth and low birth weight.

During your pregnancy:

• Do not drink alcohol.
• Do not use drugs.
• Do not use any products that contain nicotine or tobacco, such as cigarettes and e-cigarettes. If you need help quitting, ask your health care provider.
• Take a multivitamin that contains folic acid.
• Eat a healthy diet.
• Get enough rest.
• If you are experiencing a lot of stress, talk with your health care provider

Where to find support

For more support, consider:

• Talking with your health care provider.
• Consulting with a diet and nutrition specialist (dietitian).
• Joining a support group.

Where to find more information

Learn more about preventing low birth weight from:

• March of Dimes: www.marchofdimes.org/complications/low-birthweight.aspx  
• Centers for Disease Control and Prevention: ephtracking.cdc.gov/showRbLBWGrowthRetardationEnv.action  
• American Pregnancy Association: americanpregnancy.org/first-year-of-life/newborn-weight-gain  

Summary

• Babies who are born too small or born too early (prematurely) are at risk for low birth weight.
• Low birth weight can cause problems for your baby right after birth and later in life.
• The best way to prevent low birth weight is to get preconception care and prenatal care.