How many ejaculations to clean out sperm after vasectomy?

After a vasectomy, it typically takes around 15 to 20 ejaculations to clear out any remaining sperm from the reproductive system. It is recommended that patients use alternative contraception until a follow-up semen analysis confirms that sperm are no longer present. This follow-up usually occurs about 8 to 12 weeks post-surgery. However, individual experiences may vary.