After 90 days of no-scalpel vasectomy, your doctor will schedule a follow-up visit to test for sperm (if present) in your semen. A sample of your semen will be taken and tested for the presence/absence of sperm. A conventional vasectomy is successful once your surgeon confirms the absence of sperm in the semen sample. You can then stop using other methods of contraception. It usually takes around 3 months or 20 ejaculates after your procedure for your semen to be free of sperm.