By ovulation, we mean the four days before and three days after the day of ovulation, and this period of time is called the ovulation period. If ovulation does not occur during the ovulation period, then the said ovulation period is also not valid, so it is certain that ovulation will occur during the ovulation period. In the case of non-ovulation, it is likely that the ovulation is clinically dysfunctional due to some reasons, such as endocrine disorder, or thick follicular wall, or other reasons. Further examination is needed to understand the ovarian function before deciding whether ovulation treatment is needed. During the ovulation promotion process, the size of the follicles is monitored by ultrasound, and then clinically, guidance is given on when to have sex in order to improve the chances of pregnancy. Therefore, the eggs will definitely be discharged during the ovulation period.