How often and how soon we can take ecp?

It should only be used in case of an emergency within 72 hours after intercourse.

A few hours after sex is best, the longer you wait, the less effective it is. It is never 100 percent effective, goes down, less and less. After 72 hours after sex, it will have little effect.

It is for emergency use, Continued use can cause other health issues from the pills side effects.