In this video, urologist Dr. Bob Berookhim breaks down what happens when you get a vasectomy. Although this low-risk procedure is 99.9% effective as a form of birth control, you may be wondering how painful it really is or how long it takes to recover afterwards. Our expert answers these questions and more while emphasizing a few important details, such as the fact that this procedure is NOT effective right away. Although you will likely recover in a matter of days, you are still fertile until a semen analysis shows zero sperm, which happens after about 6-8 weeks.