Reproductive Failure in Males with Cystic Fibrosis

Adult males with cystic fibrosis are infertile because of failure of normal development of the vas deferens, a finding not previously recognized. Twenty-five patients over 17 years of age were found to have aspermia. Semen volume was reduced and was more acidic than that of controls. Fructose concentration was diminished. Citric acid and acid phosphatase were increased. Surgical and autopsy specimens showed an absent vas deferens. The testes appeared normal or diminished in size. The epididymides were markedly reduced or partially absent. Histologic examination of all postpubertal testes revealed decreased spermatogenesis with frequent abnormal sperm forms. Clinical examination confirmed the surgical and autopsy findings. Among 15 males with cystic fibrosis married for 46 years, only one offspring is reported. In contrast, 18 married women with cystic fibrosis have had nine children.