In women with regular periods, ovulation occurs on the 14th-16th day before the next menstrual period; in those with irregular periods, the time of ovulation varies from person to person. Ovulation is the stage when the egg matures and the probability of pregnancy is highest during this time. The probability of pregnancy increases significantly during the 72 hours before and after ovulation, so women with fertility needs can choose to have intercourse during this period. Since ovulation is easily affected by the menstrual cycle, hormonal status, emotional environment and other factors, it can occasionally be early or delayed, so if you want to know the exact ovulation period, you can monitor it with ovulation test strips, or you can have an ultrasound to understand the follicle development. The safe period is the period outside of ovulation, which means that the probability of conception is low, but if no contraceptive measures are taken during the safe period, there is also the possibility of pregnancy. If you are planning to conceive, it is recommended to increase the number of intercourse during the ovulation period to increase the chance of conception.