What Is Birth Weight?

Newborn babies vary in birth weight and size. Some low birth babies may have health issues. Get the facts on your baby's birth weight.

*Health information sourced from the Centers for Disease Control and Prevention (CDC) and MedlinePlus, a service of the U.S. National Library of Medicine. co-pay.com is not affiliated with or endorsed by the U.S. government.

What is birth weight?

Birth weight is the first weight of your baby, taken just after being born. A low birth weight means that the baby is less than 5 pounds, 8 ounces. A high birth weight means that the baby is more than 8 pounds, 13 ounces.

What can cause low birth weight?

A baby with a low birth weight can be born too small, too early (premature), or both. This can happen for many different reasons. They include:

What problems can low birth weight cause?

Babies with low birth weight may be more at risk of certain health problems. They include immediate problems, such as:

There is also a higher risk of longer-term problems, including:

What can cause high birth weight?

Causes of high birth weight can include:

What problems can high birth weight cause?

High birth weight can be a concern because it can make delivery of the baby difficult and raise the risk of birth injuries. The baby is at higher risk of problems with:

Can birth weight problems be prevented?

You may be able to prevent some birth weight problems by:

  • Getting regular checkups during pregnancy
  • Getting the right amount of nutrition and calories during pregnancy
  • Controlling your blood sugar if you have diabetes
  • Avoiding substance use during pregnancy

Get the facts on Birth Weight.

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