Birth Defects

This page has been automatically translated from English. MSDH has not reviewed this translation and is not responsible for any inaccuracies.

Birth defects are an abnormality of body structure, function or chemistry present at birth that results in physical or mental disabilities.

Birth defects are the leading cause of death in the first year of life. While there are thousands of possible types of birth defects, with health consequences that range from mild to life threatening, Down syndrome and cleft lip or cleft palate are the most common in the United States. About 5,500 babies are born each year with Down Syndrome, and about 6,800 with a cleft lip or palate.

While all the causes of birth defects are not known, some birth defects can be prevented. Actions you and your doctor take can help prevent birth defects and make a better life for your baby.

Causes of birth defects

The causes of many birth defects are still unknown. Those with known causes can be divided into four types:

  • Single-gene: These birth defects that can be inherited from just one gene from one or both parents. The parents can be perfectly healthy, and unaware that they carry a defective gene. Cystic fibrosis is an example of this.

  • Chromosomal: These are caused by abnormalities in entire chromosomes (groups of genes), or having too few or too many of a certain chromosome in the parents' reproductive cells. Although the parents are healthy, the normal development of the child is disrupted. Down syndrome is caused by a chromosomal birth defect.

  • Environmental: Environmental birth defects are caused by factors such as alcohol or chemicals that come from outside the developing child's body. The parents can control exposure to some of these factors, such as alcohol and tobacco smoke. Fetal alcohol syndrome is one example of an environmental birth defect.

  • Multi-factor: caused by a combination of several of the above.

Some birth defects can be prevented

  • Environmental birth defects can be prevented by avoiding their causes. This includes avoiding alcohol, or ensuring proper nutrition during pregnancy.
  • Inherited birth defects can be prevented by identifying them in the parents before a baby is conceived.

It's vital to visit your doctor before you become pregnant in order to identify and treat conditions that can pose a risk in pregnancy. A doctor can give advice on the lifestyle factors before and during pregnancy that can contribute to or reduce the risk of birth defects.

5 Tips for Preventing Birth Defects

  1. Be sure to take 400 micrograms (mcg) of folic acid every day.
  2. Book a visit with your healthcare provider before stopping or starting any medicine.
  3. Become up-to-date with all vaccines, including the flu shot.
  4. Before getting pregnant, try to reach a healthy weight.
  5. Boost health by avoiding harmful substances during pregnancy, such as alcohol, tobacco and other drugs.

Prevent to Protect

Infections can affect the health of your developing baby and lead to birth defects. During pregnancy, take these measures to keep your risk of infections low.

Fact Sheets and Other Resources

Last reviewed on May 18, 2021

More topics

Get COVID-19 e-mail updates daily with our free newsletter: 
Mississippi State Department of Health 570 East Woodrow Wilson Dr Jackson, MS 39216 866-HLTHY4U Contact and information

Facebook Twitter Instagram RSS

Accredited by the national Public Health Accreditation Board