Pulmonary Function Tests in Pregnancy

Clinical Indications and Safety

• The European Respiratory Society guidelines recommend regular monitoring of lung function in pregnant women with cystic fibrosis, with clinic visits at least monthly during the first and second trimesters 1

Specific Applications

Monitoring Chronic Respiratory Disease

• Women with cystic fibrosis should undergo regular lung function monitoring throughout pregnancy, with FEV₁ measurements used to guide clinical management and predict outcomes 1, 2
• Higher pre-pregnancy FEV₁ values are associated with better pregnancy outcomes and complete return of lung function postpartum 1, 2

Practical Considerations

Testing Methodology

• Upright sitting is the most comfortable position for testing during pregnancy, particularly in later trimesters 1
• Avoid supine positioning, especially during second and third trimesters, to minimize pressure from the gravid uterus on the inferior vena cava 1

Monitoring Frequency

• Monthly PFTs during first and second trimesters, increasing to every 2 weeks or more frequently as necessary 1, 2
• More frequent monitoring is recommended for those with more severe disease (FEV₁ <50% predicted) 2

Clinical Value

• Guidance for adjusting respiratory therapies and physiotherapy regimens as pregnancy progresses 1