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About CF » Pathophysiology of CF » Reproductive system

Reproductive system

Reproductive PathogenesisAbout 98% of men with CF are infertile due to abnormal development of the vas deferens in the uterus. This defect, called congenital absence of the vas deferens (CBAVD),1 prevents transport of spermatozoa from the testes or epididymis to the penis, resulting in azoospermia. CBAVD is also characterised by production of a low volume of acidic semen2 and there is evidence that the fertilising capacity of sperm is impaired by dysfunctional CFTR channels located on the surface of sperm.3 This is thought to be due to impaired transport of bicarbonate ions, which are essential to ‘prime’ sperm for fertilisation – a process called capacitation.

Although women with CF have been shown to be less fertile than their healthy counterparts, it is possible for females with severe CF to have children. Most fertility problems arise from comorbidities such as poor nutrition and/or inadequate management of CF-related diabetes mellitus.4

Congenital absence of the vas deferens (CBAVD) is characterised by abnormal development of the vas deferens.
  1. Radpour R et al. J Androl 2008;29:506–13
  2. McCallum TJ et al. Chest 2000;118:1059–62
  3. Xu WM et al. Proc Natl Acad Sci USA 2007;104:9816–21
  4. Stallings VA et al. Clinical Nutrition 2005;24:737–45