Hello! My girlfriend is about to start her third pack of the pill and recently I've been having troubles with trusting it as a form of contraception. I've been wondering, what are the chances of her getting period while on the pill? She hasn't missed a pill since day 1, starter her second pack a day earlier and I've discussed with her what kind of medications she needs to avoid. But from what I've seen there is still a very small chance of her getting pregnant, is there a way to avoid being the one percent?