The likelihood of pregnancy is relatively low if you have intercourse 8 days before your period, because 14 days before your period is the normal date of ovulation, and the likelihood of a successful pregnancy is relatively high if you have intercourse 2-3 days before or after ovulation. If you have intercourse about 8 days before your period, that is, about 6 days after ovulation, you have significantly missed the window of time when the uterine lining is receptive and able to implant the embryo successfully, so the likelihood of pregnancy is lower if you have intercourse 8 days before your period. If you want to have the possibility of pregnancy as early as possible, you can be guided by the follicular ovulation monitoring intercourse, its possibility of pregnancy will be higher.