A condom break can lead to pregnancy, yes. Darn the luck. Only not having sex is one hundred percent effective against pregnancy. If you hadn't ejaculated, that's less of a chance though so that's good. Most likely this will be fine. If pregnancy absolutely would not be tolerated, then she could use plan B or emergency contraceptive. It has to be taken within 72 hours of the incident to work and should not be used often. It will mess up her cycle and she may be irregular for 2 to 3 months which is common but it works really well. So, she could consider that but time is going to run out so act on it if she decides to take it. Ovulation takes place for most women mid month and you can get pregnant 5 days leading up to it. However, it is often not exact (ask any women who is trying to conceive, it would be a lot easier if we absolutely knew when we ovulated cycle to cycle). Anyway, think about emergency contraceptive. good luck