If your menstrual cycle is normal, with a cycle of about 28 days, ovulation is usually 14 days before your next menstrual period. 3 days after or 3 days before your menstrual period is relatively safe, even without safety measures, you will not get pregnant. However, if the physiological cycle is not normal, ovulation is not easy to calculate and may be early or wrong, and some people who have regular periods occasionally have early or wrong ovulation, it is possible to get pregnant 3 days before or 3 days after the period, so the safe period is not necessarily safe. If you don’t plan to have a baby, you should always take good contraceptive measures no matter when you have intercourse to avoid unnecessary trouble. Don’t overwork and participate in heavy physical labor during menstruation, develop good habits, go to bed early and wake up early to avoid prolonged periods and increased menstrual flow.