Asthma and cystic fibrosis in pregnancy

The prevalence of asthma in women of child-bearing age is increasing and asthma is the most common pre-existing medical disorder encountered in pregnancy. The greatest danger to the mother and fetus comes from poorly controlled or undertreated disease. Management during pregnancy should include reassurance regarding the safety of medications used to control asthma both in the antenatal period and while breastfeeding. In women with well-controlled asthma there is little or no effect on the outcome of pregnancy. However, severe, poorly-controlled asthma may have an adverse effect on fetal outcome as a result of maternal hypoxia. Management of asthma in pregnancy should prioritize disease control, the aim being freedom from symptoms both day and night. Cystic fibrosis (CF) is one of the most common fatal genetic disorders that occur in Caucasians. The prevalence of carriers is around 1:25 in many Caucasian populations and an incidence of 1:2500 live births is seen. Advances in treatment have led to an increase in the median life expectancy for people with CF to around 32 years of age. Ideally women with CF should be seen prior to pregnancy. Provided that the woman's nutritional status is good, her lung function is known and is 40% of predicted or greater, we can be reasonably positive about maternal outcome following a pregnancy. Screening for diabetes/impaired glucose intolerance should also take place. It is important also to discuss the life expectancy of the woman. Preterm delivery is the most common complication with rates of 18-45% reported and intrauterine growth restriction is also reported. Detailed knowledge about CF in addition to good links with the local CF unit should enable advice when pregnancy would be contraindicated and a good outcome in pregnant women with CF.