Ask the Expert: Eight things you should know about birth defects

January is National Birth Defects Prevention month, and Teresa Bentley, Neonatal Intensive Care Unit nurse manager at Baptist Memorial Hospital for Women, answers questions for this month’s Ask the Expert column.

1. How common are birth defects in infants?
According to the CDC, one in 33 babies is affected by birth defects. However, birth defects covers a wide range of problems, and there are hundreds to thousands of different defects that affect babies.

Some are more common than others. There are genetic defects like Trisomy 18 or Trisomy 21, which is Down syndrome, that happens from having an extra chromosome. There are also defects that are passed along in the family from the parents having a genetic characteristic that, combined, result in a defect. Finally, there are structural defects like a heart defect, cleft lip or palate, etc.

2. What are the chances of a baby being born with a birth defect?
As there are many different defects there are many different causes. There was a lot of research in recent years about spina bifida, and researchers found that the children of moms who took vitamins high in folic acid or drank orange juice had a lower occurrence.

The March of Dimes took this research and started teaching it to parents early in pregnancy, and the incidence of this defect has fallen dramatically.

Many other defects are inherited, and families need to go to genetic counseling to find out their risk of having a baby with a birth defect.

3. What are the types of birth defects?
There are defects that affect every organ of the body. Anencephaly occurs when a baby is born without a brain. Other defects can include cleft lip/palate, several different types of heart defects, spina bifida, Down syndrome, etc.

4. What are the causes of birth defects?
It varies, depending on the type of defect. It can be influenced by mom’s nutrition like the folic acid and its relationship with spina bifida. Or, it can be genetically passed along. It can be a mutation from cell division, or it can occur when twins are dividing, as in conjoined twins.

5. What are the risk factors for birth defects?
This depends on individual birth defects. If you just look at one defect, like Down syndrome, the risk for having a baby with Down syndrome significantly increases with the age of the parents. If the mom is having her first baby after 40, her risk is much greater than a mom who is in her 20’s and having her first baby.

6. What genetic factors play a role in birth defects?
Specific gene mutations can cause a child to be born with an inherited condition such as PKU or Sickle Cell Trait. Unless a family is aware of their history or risk of being a carrier of a certain type of defect, they do not receive counseling.

Often families have babies who have a defect that was diagnosed in utero by ultrasound—but this doesn’t catch every defect.

Sometimes families have an infant and were not prepared for the defect and must go through a detailed learning process to care for their baby. Often these families will have genetic counseling for their future family planning just to make them aware of the risk for each subsequent pregnancy.

7. How can birth defects be prevented?
This also depends on which individual defects. Folic acid was a great discovery for the reduction of one, but there may be other discoveries in the future to prevent other birth defects.

8. What is a common myth about birth defects?
As you can imagine, there is a lot of guilt that can be associated with having a baby with a birth defect. I think the biggest myth is that parents did something to cause the defect. Many times we never know why it happened.