Cystic Fibrosis Carrier Screening

Is Testing Right for Me? I Have My Test Results

Cystic Fibrosis Carrier Screening

What Is Cystic Fibrosis?

Cystic fibrosis (CF) is an inherited condition that causes a range of symptoms including breathing (respiratory) difficulties, digestive problems, and infertility in men.

CF causes certain organs in the body to make thick, sticky mucous. In the lungs, this mucous can cause breathing difficulties, chronic lung infections, and progressive loss of lung function. In the pancreas, the mucous interferes with the pancreatic enzymes that help break down and digest food. As a result, people with CF may have problems with growth, weight gain, and the absorption of nutrients — sometimes called "failure to thrive" in children.

Many factors affect how severe CF is, including the specific mutations that are causing CF, other genes, and environmental factors. Most often, CF develops in childhood and leads to long-term complications. The symptoms usually get worse with age and lead to a shortened life span. The average life span of a person with classic CF is the mid-30s, although that is gradually getting better with medical advances in treatment.

Occasionally, CF can have much more mild symptoms and may not be diagnosed until adulthood.

Early diagnosis and effective treatment are essential to improve quality of life and life span. Treatments are available to slow progression of the disease, reduce or relieve symptoms, and prolong lifespan. There is currently no cure for CF.

Cystic fibrosis doesn't cause changes in intelligence or appearance.

CF affects at least 30,000 children and adults in the United States. More than 10 million people in this country are unaffected carriers, meaning that they have one copy of a CF gene mutation. CF carriers are discussed further in Genetics of Cystic Fibrosis.

Next: Who Is At Risk for Cystic Fibrosis?

Would you change your family planning or test a pregnancy if you knew that there was a higher chance for you to have a child with CF?




CF testing makes the most sense for people who want the information to make different plans for having a family or who would consider prenatal diagnosis for CF. Since you said that you might change your family planning, CF testing may be a good option for you.

There are more choices if testing is done before pregnancy. If you and your partner both have CF gene mutations, you may choose to use donor egg or sperm. If you conceive with your own egg and sperm by in vitro fertilization (IVF), you may consider preimplantation genetic diagnosis. This testing is done on an embryo before it is placed into the mother. Testing can also be done during a pregnancy using CVS or amniocentesis to find out whether the baby has CF. Genetic counseling is available for parents trying to understand a diagnosis and make such decisions.

If you are sure that you would not change your family plans if you were at-risk to have a child with CF, you should consider whether or not CF testing makes sense for you. Finding out that you and your partner both have CF gene mutations means that you have much higher chance to have a child with CF. There are family planning options that can help at-risk couples lower their chances to have a baby with CF, but there are no treatments for CF during pregnancy. All children born in this country are checked for CF shortly after birth. Therefore, if a child is born with CF, the diagnosis is usually made in infancy.

If you and your partner both have CF gene mutations, you would have at least a 25% chance in each pregnancy to have a child with CF. There is no way to know before birth whether that child will have more or less severe health problems. In making your choice about CF testing, consider:

  • Do you think you have the financial, emotional, social and medical resources to care for a child with CF?
  • Would you ever consider egg or sperm donation or preimplantation genetic diagnosis to avoid a pregnancy with CF?
  • If you and your partner conceive with your own egg and sperm, how do you feel about prenatal diagnosis? CVS and amniocentesis can test for CF during pregnancy, but both procedures have a risk for pregnancy loss. How concerned are you about those risks?
  • If you had a prenatal diagnosis of CF, what would you do with that information? Would you want the information to prepare for the birth of a child with special needs? Would you consider ending a pregnancy if you knew the baby would have CF?