How soon after starting desogen (ethinyl estradiol and desogestrel) birth control can i have unprotected sex?

Unprotected sex: How soon after starting Desogen (ethinyl estradiol and desogestrel) birth control can I have unprotected sex? Everyone is biologically different, but the safe suggestion is to use a back method of contraception the first month when starting bcp's. I admit that it is somewhat inconvenient, and maybe unnecessary for most women, but it will prevent an unwanted pregnancy.

Sex/start of BCP's: Everyone is biologically different, but most experts recommend that you use a back up method of contraception the first month after starting any bcp.