Actually, it is still possible to ovulate while taking the pill. The pill works two ways, one by stopping ovulation - which is not guaranteed. The other way is by making the uterus inhospitable to implantation. The two things combined help prevent pregnancy. If you think you are still ovulating (some women can feel it) you might want to keep track, but as long as you are taking your pill correcty, you should be okay. That's the whole point of the pill!