Ovulation is usually located on the 14th-16th day before the next menstrual period, so the difference between ovulation and menstruation is 14-16 days, usually about half a month. Ovulation is a special stage during menstruation when a mature egg is discharged, and it can easily lead to pregnancy if you have sex during this stage without taking contraceptive measures. In addition, from the time of menstruation, the egg has already begun to develop in the ovary, and through continuous maturation and development, it will be discharged from the body at the time of ovulation. If you want to know the ovulation period more accurately, you can judge by the clinical symptoms, the viscosity of the leukorrhea will be stronger during the ovulation period, and the leukorrhea will be pulsatile. You can use ovulation test paper, can do ultrasound monitoring.