Birth Control Pills: When to Start & When are They Effective?

Question
Hello Doctor,

I heard a lot about birth control pills and everyone seems to have a different way for using it! I was told to start fifth day of period and so i did ! Unfortunately, later on i knew that this way doesn't offer maximum or full protection immediately, and that I had to wait for 7 days before any sexual act or use a back-up!
So as a doctor, can you please tell me when I should start bcp, when does the protection they offer start, and should I always use a back-up method (like condoms), and whether what I have been told is true or not. Can you please explain :)

Thanks

Answer
Hello Serene

Birth control pills are better taken in the first day of your cycle.i.e. the first day of bleeding. This way protection will start immediately after the end of the bleeding which is usually around day 5.
If you are taking it on day 5, you have to use a backup method for 7 days but this is for the first cycle of use. You do not have to do the same every cycle.
Under all circumstances, there is a failure rate that occurs with all methods. For example, if you have diarrhea, the pill will not be absorbed completely and protection decreases. If you take the pill daily but with a delay of more than 3 hours. e.g today at 9am and tomorrow at 1 pm, effectiveness decreases...etc

I hope this info will be helpful to you.