Cystic fibrosis and pregnancy

What is cystic fibrosis?

Cystic fibrosis (also called CF) is a chronic health condition in which very thick mucus builds up in the body. This causes problems with breathing and digestion. Digestion is the way your body processes the food you eat.

Mucus is a fluid that normally coats and protects parts of the body. It’s usually slippery and watery. But in people who have CF, the mucus is thicker and sticky. It builds up in the lungs and digestive system and can cause problems with how you breathe and digest food. The buildup of mucus in the body makes it easy for harmful bacteria to grow. This can lead to infections. 

CF is diagnosed in about 1,000 babies each year in the United States. Most people with CF are diagnosed by age 2. 

Most people who have CF can have a healthy pregnancy. But CF can cause complications before and during pregnancy. 

Can CF cause problems during pregnancy?

Yes. To best manage CF during pregnancy, you need a team of health care providers who work together to give you the best care. The team includes:

• Your prenatal care provider. This is often a doctor who specializes in high-risk pregnancies.
• Your CF doctor. This most often is a pulmonologist: a doctor who specializes in lung conditions.

Your team also may include:

• A nurse who helps you manage your overall care
• A dietitian who helps you with meal plans and nutrition and helps you manage your weight
• A social worker who helps you manage CF as part of your daily life
• A psychologist or other mental health professional who helps you deal with emotional aspects, like stress, that can come with CF
• A respiratory therapist who helps you with breathing therapy and inhaled medicines to help keep your airways clear
• A physical therapist to help you with a fitness plan

You may get your CF care at an accredited CF care center. These centers have expert providers who specialize in treating people who have CF. 

If you have CF, make sure each provider knows about your pregnancy plans before you get pregnant. Your providers work together to help you get ready for pregnancy and stay healthy during pregnancy. Your provider team monitors you closely throughout pregnancy to manage your CF and make sure you and your baby are doing well.

If you have CF, you have a higher risk for diabetes, and you can have problems with breathing, nutrition and liver function. Symptoms of CF can get worse during pregnancy. For example, you’re more likely to have pulmonary exacerbations during pregnancy. This is when your breathing gets worse.  You’re also more likely to have constipation during pregnancy. This is when you don’t have bowel movements or they don’t happen often, or your stools (poop) are hard to pass.

Some pregnancy complications are more common in people who have CF, including:

• Infertility. This means you have trouble getting pregnant.
• Premature birth. This is when your baby is born early, before 37 weeks of pregnancy. Babies born early are more likely to have health problems at birth and later in life than babies who are born on or close to their due date.
• Gestational diabetes. This is a kind of diabetes that some people get during pregnancy. Diabetes is a medical condition in which there’s too much sugar (also called glucose) in the blood. This can damage organs, including blood vessels, nerves, eyes and kidneys. If you have CF and don’t have  diabetes before you became pregnant, you’re at increased risk to develop gestational diabetes.
• Not gaining enough weight during pregnancy. Your nutrition needs change during pregnancy. This can cause you to lose weight or not gain enough weight during pregnancy. Gaining the right amount of weight during pregnancy helps support your baby’s growth and development.
• Vitamin A toxicity. This means you have too much vitamin A in your body. Vitamin A helps your body fight infections and helps you have healthy skin, vision and intestines. If you have CF, you may not absorb as much vitamin A as you should, so you may need to take a vitamin A supplement to help you get the right amount. But during pregnancy, you can have too much vitamin A, and that can affect your baby’s development.
• High blood pressure (also called hypertension). This is when the force of blood against the walls of the blood vessels is too high. It can stress your heart and cause problems during pregnancy.

What causes CF?

CF is a genetic condition. This means it’s passed from parents to children through genes. A gene is a part of your body’s cells that stores instructions for the way your body grows and works. Genes come in pairs — you get one of each pair from each parent. CF is one of the most common genetic conditions in the United States.

Sometimes the instructions in genes change. The gene change in CF affects a protein that controls the balance of salt and water in the body. This causes the body to make thick, sticky mucus and salty sweat.

Parents can pass gene changes to their children. Sometimes a gene change can cause a gene to not work correctly. Sometimes it can cause birth defects or other health conditions.

You have to inherit the gene change for CF from both parents to have CF. If you inherit the gene change from just one parent, you have the gene change for CF, but you don’t have the condition. When this happens, you’re called a CF carrier.

If you and your partner are both CF carriers, your baby may get two CF gene changes (one from each of you) and have CF. About 1 in every 20 people is a CF carrier. If you and your partner are both CF carriers, there is a:

• 3-in-4 chance (75 percent) that your baby won’t have CF
• 1-in-2 chance (50 percent) that your child won’t have CF but will be a CF carrier
• 1-in-4 chance (25 percent) that your child will have CF
• 1-in-4 chance (25 percent) that your child will not have CF and not be a carrier 

If you and your partner both have CF, your baby will have CF. However, CF affects the sperm count in semen, making it almost impossible for a parent with CF to fertilize an egg with their sperm. Genetic counseling can help you understand your chances of passing CF to your baby. A genetic counselor is a person who can help you understand about how genes, birth defects and other medical conditions run in families, and how they can affect your health and your baby's health. Ask your health care provider if you need help finding a genetic counselor, or contact the National Society of Genetic Counselors. 

How can you find out if you’re a CF carrier?

You can get carrier screening before or during pregnancy to find out if you’re a CF carrier. There are two kinds of carrier screening tests: 

1. A blood test
2. A saliva test. Saliva is the clear liquid inside your mouth. 

Your provider sends the blood or saliva sample to a lab for testing. Both tests are safe to take during pregnancy. 

Carrier screening is your choice. You don’t have to have it if you don’t want it, even if your provider recommends it. All pregnant people or those who are thinking about getting pregnant can get screened for CF. If screening shows that you’re a CF carrier, your partner can get screening, too.

About one in 31 people in the United States is a CF carrier. You and your partner may want to have CF carrier testing if:

• CF runs in either of your families.
• You are: 
  • White. About 1 in 29 White Americans is a CF carrier. It’s most common in those whose families come from Northern Europe.
  • Latinx. One in 46 Latinx people in the United States is a CF carrier.
  • Black. One in 65 Black people in the United States is a CF carrier.
  • Asian. One in 90 Asian people in the United States is a CF carrier.

Can you find out during pregnancy if your baby has CF or is a CF carrier? 

Yes. If you or your partner has CF or is a CF carrier, you can have a prenatal test to find out if your baby has the condition or is a carrier. You can have either of these tests:

• Chorionic villus sampling
• Amniocentesis 

If you think your baby may have CF or be a carrier, talk with your provider or genetic counselor about these tests.

How is CF treated during pregnancy?

All of your providers work together to make sure your CF treatment is safe for you and your baby during pregnancy. Treatment can include:

• Medicine, like antibiotics to treat infections
• Inhalers to open the airways to the lungs and thin mucus
• Chest therapy to help clear the airways to the lungs
• A fitness plan
• Supplements to help your body get nutrients that it may not be able to get from food

Most likely you can continue your regular CF treatment throughout pregnancy, but you may need to make some changes. For example, certain antibiotics that you take to treat infections may not be safe for your baby during pregnancy. You may need to switch to a safer medicine. Or you may need to change the timing of certain treatments. Your provider team can help you make decisions about treatment that are best for both you and your baby. 

If you have CF, here’s what you can do to help you have a healthy pregnancy:

• Get early and regular prenatal care and go to all of your prenatal checkups, even if you’re feeling fine.  At each visit, talk to your provider about your CF, your treatment plan and keeping your other providers informed about your prenatal care.
• Tell your prenatal care provider about any medicine you take, even if it’s prescribed by another provider. Be sure any provider who prescribes you medicine knows that you’re pregnant. Don’t start or stop taking any prescription medicine during pregnancy without talking to your providers first. Stopping your medicine suddenly may cause severe problems for you and your baby.
• Get regular treatment for CF. Don’t stop getting CF treatment because you’re going to your prenatal care checkups. You need to see both your prenatal provider and your CF providers throughout pregnancy.  

Can you breastfeed or chestfeed if you have CF?

Yes. Even if you have CF, human milk is good for your baby, but it takes a lot of energy for a body to make milk. This may make it hard for you to get all the calories you need for both you and your baby. Work with your dietitian on a meal plan to make sure you get enough calories each day. 

Medicines you take sometimes pass to your baby through your milk, and some may be harmful to your baby. Make sure your prenatal provider, your CF provider and your baby’s provider know about any medicine you take.

More information

Cystic Fibrosis Foundation

See also: Cystic fibrosis and your baby, Newborn screening, Your family health history

Last reviewed: May, 2021