What does the pill do if starting the pack after ovulation when there is no egg to prevent to release? does it only thicken the mucus in cervix? few days after ovulation chance of conceiving is low so do you still need to wait 7 days when on the pill?

If one has regular periods (24-32 days apart), starting a oral bcp regimen should begin one the second or third day of an expected menstruation, and the active pills taken w/in the hour of the prior day's active pill. Starting "after ovulation" is like using bcp's as a "morning after" contraceptive, and is far less than 100% in preventing pregnancy.