Condom broke in the middle of having sex. i pulled out as soon as i noticed. she takes birth control off/on. should we take other precautions?

Yes: You just had unprotected sex, and if you don't want pregnancy she needs to do Plan B asap. Taking birth control 'on & off' is equivalent to not at all. If she is not going to do it consistently, she really is better off not doing it at all. And pulling out with a broken condom is not protective either - the damage is done. She has 72 hours to get plan b, and the sooner the better to prevent preg.