There is no definite number of times to monitor ovulation by ultrasound, usually it takes about 5-7 times. The growth and development of follicles can be detected by ultrasound, usually starting from day 10 of the menstrual cycle, with monitoring once a day. The number of times of monitoring can be increased to twice a day when the dominant follicle is approaching, which refers to follicles with a diameter of 1.8-2.0 cm. These follicles are easily conceivable when they are mature and ovulating. This is a very easy way to conceive when these follicles are mature and ovulating. It is important to increase monitoring around the day of ovulation until the dominant follicle is not detected, indicating that ovulation may have occurred, and women who are planning to conceive can arrange sex appropriately to increase their chances of conception. In addition, for women with regular menstruation, the ovulation day can be calculated according to the menstrual cycle, which is around the 14th day before the next menstrual period, or you can use the basal body temperature or ovulation test paper to detect ovulation.