You can’t usually get pregnant if you have intercourse 4-5 days before your period. This is because a woman’s ovulation period is 14 days before the next menstrual period, when the egg cell is discharged from the ovary and survives in the woman’s body for about 24 hours. If the egg is not fertilized within 24 hours, it will be naturally absorbed by the body. And 4-5 days before menstruation, the egg has been discharged for about 10 days, at which time the egg cell no longer exists. If there is no egg at the time of intercourse basically will not get pregnant, so at this time is relatively safe.