You are not sterile once you have had the procedure, there will be millions of live sperm remaining. You will be fertile for another 3-4 months. It will take 24-30 ejaculations to clear all the sperm and you will need to continue with another form of contraception until you have sent your semen test for analysis at 16 weeks and received an all clear result. At the time of your appointment, we will provide you with a sample pot and information regarding a Post Vasectomy Semen Test. It is very important that you take this test and that you wait for the results before you stop using the other methods of birth control.