That all depends. Are you in the first three months of taking it? If so, it's not unusual for your body to skip a period during this time because it's getting used to being on the pill. If you've been taking it correctly every day and on time, I wouldn't worry about it, it will eventually come. If, however, you've been skipping pills or taking them really late in excess of say 12 hours or more, then the possibility of pregnancy exists.