Typically, the second test is done 20 weeks post vasectomy. Semen testing after vasectomy is an essential part of the process, is it confirms the absence of sperm in your semen (azoospermia) and removes the risk of getting an unwanted pregnancy. In fact, you will need to produce various samples during a determined period of time to make sure that the presence of sperm does not reappear in your sample.
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