Cystic Fibrosis Screening
What is cystic fibrosis?
Cystic Fibrosis (CF) is a chronic, progressive, inherited disease of the body's mucous glands that primarily affects the respiratory and digestive systems. Symptoms of CF include: thick, sticky mucus in the lungs, persistent coughing, wheezing, frequent lung infections, poor growth, persistent diarrhea and infertility. CF symptoms can vary greatly from mild to very severe. About 30,000 Americans have CF and about 2,500 babies are born with CF each year in the United States. Today, the average lifespan of someone with CF is 30 years. There is no cure for CF- current treatment is aimed at easing the symptoms of the disease and slowing its progression. Treatment includes physical therapy, daily medications and dietary supplements. Cystic Fibrosis does not affect intelligence or appearance. Patient's with cystic fibrosis usually have a shortened life span and have many special health needs. The severity of the disease is not the same in all people affected, and it is not possible to tell how severe the affliction will be from prenatal testing.
Why should I be tested?
About one in 30 Caucasian people carry the CF gene. If your background is not Caucasian, your chances of carrying the gene are slightly lower. The purpose of CF carrier testing is to see if a couple is at increased risk for giving birth to a child who will have CF. Cystic Fibrosis carrier testing is a laboratory test done on a sample of blood or saliva. If testing shows that a couple is at high risk, additional testing can be done on the developing baby to see whether or not it will have CF. However, most women's test results are normal.
Cystic Fibrosis cannot be treated before birth. The purpose of having this information about your developing baby is so you can prepare yourself to care for a child with special health care needs or so you can terminate the pregnancy.
Could I be a carrier of cystic fibrosis?
Yes. You could be a carrier of CF even if no one in your family has CF and even if you already have children without CF. Carrier testing is being made available to you on a voluntary basis. Testing can be right for some people and not right for others based on many factors. These include your level of risk, your family situation, plans and needs, and your religious and spiritual beliefs. Whether or not you are tested is a personal decision that belongs to you and your baby's father.
If my test result is normal, could I still be a carrier?
Yes. There are some mutations in the CF gene that the current test cannot find. For this reason, you could be told your test result is normal and you could still be a carrier. Like most medical tests, this one has limitations because not all CF mutations are known. However, these unknown CF mutations are rare. The likelihood that you are a carrier even though you had a normal result is very small.
If the test shows I am a carrier, what should I do?
If the test shows that you are a carrier, the next step is to test the baby's father. Both parents must be carriers for the baby to have CF. If the father has a normal test result, the chance that your baby will have CF is very, very small. This remaining risk is because the test is not 100% accurate, as mentioned in the previous section. However, since this is a very rare occurrence, if you are a carrier but the father has a normal result, no further testing would be recommended.
What if both my partner and I are cystic fibrosis carriers?
If two people who are both carriers have a child, that child may have CF. When two carriers have a child together, there is a 1-in-4 (25%) chance with each pregnancy that the child will have CF. This is true even if they already have other children with-or without-CF. If CF testing shows both parents are carriers, you will see a provider for genetic counseling. This person will give you more information and help you decide if you want to test the baby for CF. This could be done around the 11th week of pregnancy using CVS (chorionic villus sampling). This involves removing a tiny piece of the placenta. Or it could be done around the 16th week of pregnancy using amniocentesis, a procedure where a needle is used to take fluid from around the baby for testing. If either test shows that the baby will develop CF, you could choose to either terminate or continue the pregnancy.
If I had cystic fibrosis testing, do I need it again?
If the test shows you are a carrier, the result is definite and will not change. However, if you are a carrier and have a new partner for a future pregnancy, testing should be considered for that new partner. If you test negative now and become pregnant in the future, you should discuss CF carrier testing at that time with your provider, as test technology changes.
How do I decide whether or not to have carrier testing?
After learning about CF carrier testing, some people decide to have testing, and others decide against it. The cost of testing is covered by some insurance and not by others. You may want to check with your insurance company before deciding if you want testing.
Listed as follows are some reasons other people have given for having or not having CF testing.
Possible reasons to be tested: