Cystic fibrosis (CF) is a life-long disease that causes problems with digestion and breathing. It is usually diagnosed early in childhood and is treated with medications and respiratory therapy to clear the mucus from the lungs. Children who have CF can get frequent lung infections and often require hospitalization.
Cystic fibrosis is caused by a mistake in both copies of the CF gene. CF carriers have a mistake in one copy of the gene and do not have any symptoms. Even if no one in your family has ever had CF, you could still be a carrier. Your risk of being a carrier is based on your ethnic background. If you are white or of European or Ashkenazi Jewish descent, your chance of being a carrier is 1 in 29 or about 3%. If you are Hispanic your risk is 1 in 46. African Americans have a risk of 1 in 62 and Asian Americans of 1 in 90. Your baby can have CF only if both parents are carriers.
If you feel your risk is high enough, you may want to have the blood test to see if you are a carrier. Unfortunately, the blood test cannot pick up all of the mistakes that can occur in the CF gene. It is possible to have a negative test but still pass an abnormal gene to your child, but this is very unlikely. If you have a carrier test for CF and an abnormal gene is found, your partner should be tested. If your partner also has an abnormal gene, there is a 1 in 4 chance (25%) that your baby will have CF. You can have a test during the pregnancy (amniocentesis or chorionic villus sampling) to see if your baby has the disease. If your baby is affected, you can choose to terminate or continue the pregnancy.