If you have intercourse on the 8th day of your period, you may be ovulating and have a higher chance of getting pregnant, so it is recommended to take the oral emergency contraceptive pill. Because ovulation is about 14 days before menstruation, if your menstrual cycle is very accurate at 28-30 days, you will be ovulating around day 16 from the first day of menstruation. Even if it is not in the ovulation period it will hover around the ovulation period because the sperm will remain in the vagina for 48 hours, which will increase the chances of conception, to take oral emergency contraceptive pills, if in the absence of wanting children. Also if the menstrual cycle is confused, delayed or early for a long time, ovulation will also be confused with it, which will increase the chances of conception, and again the emergency contraceptive pill should be taken orally to avoid any chance of conception.