We describe a 23-year-old Delta F508 homozygote cystic fibrosis primigravida. At the onset of gestation, she had mild to moderate pulmonary involvement, exocrine pancreatic insufficiency, focal biliary cirrhosis, satisfactory nutritional status and normal fasting and post-prandial glucose blood levels. At 29 weeks, she developed polyhydramnion and gestational diabetes. At 37 weeks, she was delivered of a live 2,980 g boy by caesarean section under epidural anaesthesia. Insulin was subsequently discontinued and her pulmonary function improved spontaneously. Neither maternal nor neonatal health problems were observed during the 3-month follow-up.