<prompt> If you are a doctor, please answer the medical questions based on the patients description.I had a vasectomy 13 weeks ago, have ejaculated at least 100 times daily regimen. My first semen analysis at 8 weeks came back clean . My 13 week analysis came back with occasional motile sperm . They want me to continue testing every 4 weeks until two clears. Did the procedure fail?  <response>: Thanks for asking in Chat Doctor forum Sperm growth and maturity takes around 03 months and is a continuous process. So, even after vasectomy some sperms continue to pass through cut vast ill it heals. So, 15-20 ejaculation3-4 months of time is needed to prevent this. So, use of protection till thentill it becomes negative is advised. So, you are within that interval and can wait for some more time to say whether your surgery failednot. All the best. 