Despite reduced fertility, pregnancy is likely to occur with increasing frequency in cystic fibrosis in proportion to the number of patients reaching childbearing age. Thirty-eight pregnancies in 25 patients with cystic fibrosis are presented. Twelve of the 25 mothers were pancreatic-sufficient. Despite previous reports of the hazards of pregnancy in cystic fibrosis, we found that pregnancy was well tolerated by the vast majority of our patients and had little effect on their pulmonary and nutritional status. Therapeutic abortion for medical indications was required in two pregnancies. The incidence of prematurity and the neonatal mortality rate were low, and no congenital abnormalities occurred. We conclude that pregnancy can be tolerated by the majority of cystic fibrosis patients, particularly those who are pancreatic-sufficient.