Cystic fibrosis (CF) is the most common genetic disorder in white persons, and a small number of white men have CF mutations. These men might lack the vas deferens on both sides. This means that sperm cells cannot mix with the ejaculate, so the ejaculate will not include any sperm (azoospermia). To achieve pregnancy, sperm must be collected directly from the testicles by a biopsy. In the case of CF as the cause of male infertility, the female partner should also be genetically tested for CF. Two carrier parents have a 50% chance of having a child with CF.
Vasectomy is a surgical procedure that disconnects the epididymis from the vas deferens to make the man infertile. This procedure is permanent and is considered to be irreversible. In some cases it can be reversed, but the chance of success depends on when the vasectomy has taken place.
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Problems with ejaculation
In some cases, the ejaculate cannot reach the urethra. The man might not be able to ejaculate, it might be delayed, or the semen might go into the bladder(retrograde ejaculation). Causes can be psychological, physical (for example, nervous system dysfunction after surgery or trauma), or related to medication use. Treatment options include medication and physical stimulation.