Birth defects are abnormalities present at the time of a baby’s birth. They occur in approximately 3% of pregnancies. It’s possible that you may be at increased risk for certain types of birth defects and therefore may want to consider special counseling and/or testing prior to becoming pregnant.
1) Structural Birth Defects: When some part of the baby’s body did not form correctly or completely, this is a structural birth defect. For example, neural tube defects (e.g. spina bifida, anencephaly) result when the coverings over the spinal cord or brain do not close properly. The folic acid in your prenatal vitamins can help prevent neural tube defects, but to be effective, must be taken before pregnancy (that is, while you are attempting to conceive) and in early pregnancy. There is no single cause of structural defects, but certain medical conditions such as diabetes can be associated with a higher risk.
2) Birth Defects Due to Infection: If certain infections are acquired by the mother during pregnancy, they can cause abnormalities in the baby. Rubella (German measles) and varicella (chickenpox) are two examples. If you have not already had these diseases or been vaccinated, you should be vaccinated at least one month before becoming pregnant.
3) Prenatal Screening for Genetic Disorders: It’s possible that you are unknowingly a carrier of a genetic disorder that could be passed on to your baby. Some inheritable diseases are more common among individuals of certain ethnicities. For example:
- African-American: Sickle cell
- Caucasian: Cystic Fibrosis
- Ashkenazi Jewish: Tay-Sachs, Canavan disease, Cystic Fibrosis, Familial Dysautonomia
- Asian: Thalasemia
Blood tests can be performed either before conception (preconceptual) or early in pregnancy to find out whether either parent is a carrier of certain genetic defects that could affect the health of the baby. If you fall into one of the above ethnic categories, you may want to consider getting tested before you are pregnant.
Watch for a future post on testing for Down’s Syndrome and other abnormalities in early pregnancy.