Ovulation is the period before and after the egg is discharged, usually about 14 days after menstruation and before the next menstruation. In the case of normal menstruation, the day of ovulation for women is about 14 days before the next menstrual period. Usually, the 5 days before and 4 days after the day of ovulation, together with the day of ovulation for a total of 10 days, are called the ovulation period. The projection of ovulation is only suitable for women with regular menstrual cycles, e.g. if the menstrual cycle is 28 days, ovulation usually occurs on the 14th day of the cycle, and if the menstrual cycle is 30 days, ovulation will occur on the 16th day of the cycle. In women who are ovulating, vaginal discharge may appear to be significantly increased and strained. Women with regular menstrual cycles can predict ovulation by counting their menstrual cycles, and increasing the number of intercourse sessions during ovulation will increase the chances of conception. For women with irregular menstrual cycles, it is difficult to predict the ovulation period through the menstrual cycle, which can usually be predicted through ovulation test paper or ultrasound testing.