With proper management, careful monitoring, and working closely with your care team and obstetric team, many women with cystic fibrosis are able to carry a child without significantly impacting their long-term health. At the same time, however, the unique demands that pregnancy places on the body can have serious implications for women with CF.
The progressive decline in lung function and impaired nutrition associated with CF can pose several challenges, including a higher risk for health complications and an increased treatment burden. For this reason, women with CF who plan their pregnancies for a time when they are in the best health possible tend to have the most successful outcomes.
Am I Healthy Enough for Pregnancy?
Generally, there are four main factors that help determine how well a woman with CF will handle pregnancy. These factors are:
- Lung function: Ideally, a woman with CF should have a forced expiratory volume (FEV1) of 50 percent or more before becoming pregnant. Women with lower FEV1 values can also get pregnant, but their risk for problems and other complications may be higher. According to many experts, your lung function is the most important factor that affects both your health and the baby's after delivery. Research has shown that the outcomes for you and your baby will likely be better if your FEV1 is over 50 percent before you get pregnant.
- B. cepacia: Some studies have shown that infection with Burkholderia cepacia can lead to more problems during pregnancy. If you have B. cepacia and are interested in becoming pregnant, talk to your CF care team to learn more about the possible implications for both your and your baby's health.
- Nutrition: Before getting pregnant, it is important that your nutrition status is good enough to support both you and your baby throughout your pregnancy, including potential morning sickness or changes in appetite. This means having a body mass index (BMI) of at least 22 kilograms per square meter (kg/m2). If your BMI is below this, improving your nutritional status before you get pregnant would benefit you and your baby, as low BMI in pregnancy is associated with problems including poor fetal growth and premature delivery.
- Cystic fibrosis-related diabetes: For women with CF who have cystic fibrosis-related diabetes (CFRD), monitoring and controlling your blood glucose prior to getting pregnant will be key. Diabetes has been shown to increase your risk of experiencing problems during pregnancy, so it is important to discuss your CFRD with your care team. If you are taking insulin to control your diabetes, your insulin requirements may change once you are pregnant.
- Cirrhosis (liver disease): CF can be associated with severe liver disease, such as cirrhosis. Liver disease is also a potential complication of pregnancy with CF. For this reason, women with CF who have liver disease should discuss the implications of getting pregnant with their CF care team.
Talk to your CF care team about important considerations if you are taking a CFTR modulator and are planning to get pregnant.
Potential Complications of Pregnancy With CF
According to several studies, the majority of CF pregnancies result in live births and there is no clear increased risk of fetal death or birth defects. However, this is not to say that getting pregnant with CF comes without risks.
The most common complication of pregnancy with CF is preterm or premature delivery, which, in one study, was associated with low pre-pregnancy lung function.1 Diabetes was also reported to be more common in women who delivered prematurely.
Overall, adequate nutrition, well-controlled blood sugars, and a reasonable pre-pregnancy FEV1 are associated with better outcomes.
In addition to premature delivery, some of the most common complications associated with pregnancy and CF include:
- Gestational diabetes: Pregnant women with CF have been found to have a higher risk of gestational diabetes than those in the general population. Many women with CF already have impaired glucose tolerance. Because the hormonal changes that accompany normal pregnancy often cause a degree of impaired glucose tolerance as well, women with CF are more likely to develop gestational diabetes than the average pregnant woman. For this reason, your care team should consistently screen for diabetes throughout your pregnancy.
- Nutritional deficiency: Because your nutritional demands will change during pregnancy and put you at risk for inadequate weight gain or weight loss, most women with CF will need to increase their caloric intake, drink supplements, and focus on maintaining and gaining weight while pregnant. Many women with CF need to take nutritional supplements during pregnancy, so it is important to pay close attention to your nutritional status and work closely with your CF dietitian or another member of your care team.
- Constipation: Although it is common for all women to experience constipation issues during pregnancy, having CF puts you at a higher risk. To prevent constipation, pregnant women with CF can try taking steps such as drinking more water, adding fiber to their diet, and eating more fruits and vegetables. In addition, your care team may recommend the use of stool softeners or laxatives while you are pregnant. Contact your CF care team if you notice a decrease in the number or amount of normal stools.
- Exacerbations: Pregnant women with CF may experience more exacerbations, so it is important that you continue your CF respiratory therapies throughout pregnancy to stay as healthy as possible. Your CF care team and obstetrician will want to discuss whether any of your treatments should be stopped or changed during pregnancy — especially if you require antibiotics.
- Vitamin A (retinol) toxicity: Because high levels of vitamin A — especially within the first three months — can be associated with developmental issues for your baby, it is important that your care team carefully monitors your vitamin A levels when managing your pregnancy. If you are taking vitamin A supplements, your obstetrician will likely have you stop taking them during your pregnancy. However, it is important that you do not stop taking your other CF-related vitamins without discussing it with your care team and obstetrician first.
- Hypertension: According to some studies, pregnant women with CF have a higher risk of hypertension than pregnant women without CF. For this reason, your care team and obstetrician should closely monitor your blood pressure both before and during your pregnancy.
Dealing With the Unexpected
Although planning your pregnancy as a woman with CF is ideal, life does not always go according to plan. If you are a woman with CF experiencing an unexpected pregnancy, your first step should be to contact your CF care team. Your care team will work with you to assess the possible impact that being pregnant could have on your health, and ultimately help you weigh the risks and benefits.
The decision about how to proceed in the face of an unplanned pregnancy will depend on the trimester, as well as many other factors. For example, some people with CF may feel it would be difficult to care for both themselves and a child with CF, so getting your partner genetically tested could play a major role in your decision process.
In addition, women with severe lung disease may need to consider terminating the pregnancy to preserve their own health. Only you can decide what is right for you, but discussing both the physical and emotional implications of your pregnancy with your CF care team can help you make an informed decision.
1 Gilljam M, Antoniou M, Shin J, Dupuis A, Corey M, Tullis DE. Pregnancy in cystic fibrosis. Fetal and maternal outcome. Chest. Jul 2000;118(1):85-91.