Facts about Birth Defects

Major birth defects are conditions that cause structural changes in one or more parts of the body; are present at birth; and have a serious, adverse effect on health, development, or functional ability.

About one in every 33 babies is born with a birth defect.¹ Birth defects are a leading cause of infant death, accounting for more than 1 of every 5 infant deaths.² In addition, babies born with birth defects have a greater chance of illness and long term disability than babies without birth defects.  

Prevention

Some birth defects can be prevented. There are things that a woman can do before and during pregnancy to increase her chance of having a healthy baby: 

• Take 400 mcg of folic acid every day, starting at least one month before getting pregnant.
  
• Don’t drink alcohol, smoke, or use “street” drugs.
  
• Talk to a health care provider about taking any medications, including prescription and over-the-counter medications and dietary or herbal supplements. Also talk to a doctor before stopping any medications that are needed to treat health conditions.
  
• Learn how to prevent infections during pregnancy.
  
• If possible, be sure any medical conditions are under control, before becoming pregnant. Some conditions that increase the risk for birth defects include diabetes and obesity.

If you are pregnant or planning to get pregnant, see your healthcare provider.  Prenatal (before birth) care can help find some problems early in pregnancy so that they can be monitored or treated before birth.

More tips to prevent birth defects »

Causes and Risk Factors

Birth defects occur before a baby is born.  Most birth defects occur in the first 3 months of pregnancy, when the organs of the baby are forming.  This is a very important stage of development.  However, some birth defects occur later in pregnancy. During the last six months of pregnancy, the tissues and organs continue to grow and develop.

Most birth defects are thought to be caused by a complex mix of factors. These factors include our genes, our behaviors, and things in the environment. For some birth defects, we know the cause. But for most, we don’t.

We do know that some women have a higher chance of having a child with a birth defect:

• Women who take certain drugs, smoke, or drink alcohol during pregnancy.
  
• Women with certain medical conditions, such as diabetes or obesity.
  
• Women who take certain medications that are known to cause birth defects, such as isotretinoin (a drug used to treat severe acne).
  
• Women who have someone in their family with a birth defect. To learn more about your risk of having a baby with a birth defect, you can talk with a clinical geneticist or a genetic counselor.
  
• Women over the age of 35 years.

Learn about CDC’s research on causes and risk factors »

Diagnosis

A birth defect can be found before birth, at birth, or anytime after birth. Most birth defects are found within the first year of life. Some birth defects (such as cleft lip or clubfoot) are easy to see, but others (such as heart defects or hearing loss) are found using special tests, such as x-rays, CT scans, or hearing tests.  

Learn more about diagnosis »

Specific Birth Defects

Birth defects can affect almost any part of the body (e.g., heart, brain, foot).  They may affect how the body looks, works, or both.  Birth defects can vary from mild to severe. The well-being of the child depends mostly on which organ or body part is involved and how much it is affected.

Learn about specific birth defects »

Living with a Birth Defect

If your child has a birth defect, you should ask his or her doctor about local resources and treatment.  Geneticists, genetic counselors, and other specialists are another resource.