Is birth control effective before 7 days of use ( mid cycle ) ? like how effective does it get day by day until the 7th day?

Wouldn't bet on it: The pill works by providing a constant level of hormone in your system that fools the body into thinking you are pregnant so you don't release eggs.Most docs want you to use a backup BC for the first month until your body adapts to the med.The med makers often suggest it is effective after about 2 wks.If you release an egg before the med stops it, you are at risk if sexually active.