The ovulation period for pregnancy should be analyzed according to different situations of women. For women with regular menstrual cycles, the exact date of ovulation is 14 days before the next menstrual period, which is the approximate date of ovulation. For women with irregular menstrual cycles, the exact date of ovulation cannot be measured in this way. In this case, ultrasound monitoring can be performed to monitor ovulation, for example, 7-8 days after the onset of menstruation, to check the development of the follicles. If the follicle reaches 18-20mm by ultrasound monitoring, the follicle is mature and the date of ovulation is imminent, at which time guided coitus will increase the likelihood of successful conception.