You can have sex after you have healed from your vasectomy, but you should use another form of protection to prevent pregnancy until your semen has been tested to prove no more sperm are present. Sperm can survive for several months in the vas deferens above the point where the tube was interrupted. It can take 30 ejaculations to completely empty the vas deferens of sperm. Dr. Turek will ask you to provide a semen sample approximately three months after vasectomy; at this point, 90 percent of men have no sperm in their ejaculate.