How long do you have to take birth control before it is effective? ?

My period started on monday, and that is when I started taking birth control. How long before it is effective against preventing pregnancy? And if I use the standard days method, does that mean that I can have unprotected sex this weekend? How long do you have to take birth control before it is effective? ?
You're fully protected once you have taken an active pill each day for at least seven days in a row, so you won't be protected until you have taken next Monday's pill.





But if you started the pill on the very first day of your period, you are protected immediately





This is what the instruction leaflet of my BC pill says. You should check yours to make sure, otherwise wait the full 7 days,How long do you have to take birth control before it is effective? ?
Bruce: All the BC is going to do is make it so you do not have to shave your face.





If you are talking about ur girlfriend, or if u are a chick named Bruce, you should go through one month of pills before having unprotected sex. The pills taken during your period are just place fillers (sugar pills) and have no effect.
it takes 7 days for the pill to be effective