I've been on the patch for over a year & a half now & have had unprotected sex almost everytime, and trust me....that's a lot of times! My boyfriend & i never use a condom or any other type of protection, i just wear my patch, make sure i change it the right day every week, and i've had no problems whatsoever. I know everyone's body is different....so if you are still kinda wondering about it, depending on how long you've been on the patch, you might wanna give yourself a couple months or so to make sure your body is gonna work with the patch...periods are regular, etc. The patch is about 99% effective, just like the pill, and most people don't use condoms when on birth control....yes, there is always that little bit of a chance, but more than likely....and lets hope for your sake & mine....it's very unlikely! :)