Almost all men with cystic fibrosis have CBAVD. It results from improper development of the vas deferens and causes infertility. The vas deferens is a tube through which sperm travel from the testi to the ejaculatory duct. A man born with CBAVD typically produces sufficient quantities of sperm. But, the sperm never reach their intended destination because there is no transport system. The same transport interruption occurs when a man has a vasectomy.
A man diagnosed with CBAVD, who does not show signs of cystic fibrosis, should undergo a standard diagnostic work-up at a local CF clinic – including a sweat chloride test and screening for subtle lung disease. Men with CBAVD should consult with a clinician as they may have a milder form of cystic fibrosis.