Protected sex with a condom then first week of starting birth control? chances of getting pregnant?

Low: Many suggest you have a 2nd BC until your body gets used to the pill, or about a month.Some pill makers say their product is effective after 2 wks. I like to err on the side of caution.

Possible: Birth control pills usually start acting right away for preventing pregnancy but reach their full potential as contraceptives if you have taken them for at least 1 month. Please continue to use condoms for 1 month. If you are really worried, then take Plan B now and continue to use the pill pack after the Plan B as usual (and use condoms too). Check a home pregnancy test after 2 and 4 weeks