It is possible to get pregnant if you have intercourse on the fourth day of your period. Because every woman has her own fixed menstrual cycle and ovulation period, ovulation is calculated by projecting 14 days before and after the first day of the next menstrual period, and the 4-5 days before and after this day are considered as ovulation period. In other words, ovulation lasts about a week. If a woman’s menstrual cycle is short, 23-24 days is a menstrual cycle, the fourth day of her period is exactly within the ovulation period. Therefore, it is possible to get pregnant if you have intercourse on the fourth day of your period. There are many contraceptive methods available, including condoms, IUD placement or birth control pills, so you can choose the one that suits your situation.