Each woman’s menstrual cycle is different, so follicle monitoring does not need to be done daily. If the menstrual cycle is 30 days, monitoring can be done around the 10th day of menstruation. When the follicles grow to about 1.0-1.3cm, monitoring is done once every two days. When the follicles reach 1.7 cm, it means that there is a dominant follicle and can be monitored every day, usually about 2 cm can be ovulated, so the monitoring can guide pregnancy. When the follicle disappears or there is a small amount of free fluid in the pelvis, and the follicle is <5cm, it proves that ovulation has occurred. The whole ovulation monitoring needs 4-5 times, at least three times. In addition to follicle monitoring, women can also determine whether they are ovulating by observing changes in their leukorrhea and body temperature. For example, egg-white, thin, stretched leukorrhea or an increase in body temperature can indicate ovulation. Therefore, ovulation can be determined by monitoring follicles, observing changes in leukorrhea and body temperature, and then scheduling intercourse.