Diagnosis of maternal cystic fibrosis during pregnancy.

The third and fourth cases of maternal cystic fibrosis diagnosed during pregnancy are presented. Quantitative pilocarpine iontophoresis (sweat chlorides) must be performed to establish the diagnosis. Other important findings include recurrent or persistent respiratory symptoms, chest x-ray abnormalities, abnormal pulmonary function studies, and abnormal arterial blood gases. Gastrointestinal tract dysfunction and a positive family history for respiratory disease also suggest the diagnosis. Pregnant patients with cystic fibrosis require careful and frequent cardiopulmonary and gastrointestinal surveillance. A higher incidence of premature labor is noted and all patients are best managed in tertiary referral centers. Patients should also be monitored carefully during the puerperium because maternal pulmonary decompensation may occur during this time.