For women with regular menstrual cycles, ovulation occurs from the 9th to the 18th of the following month when menstruation occurs on the 30th, but there may be individual differences. In women with regular menstrual cycles, ovulation occurs about 14 days before the next menstrual period, so when menstruation occurs on the 30th, ovulation occurs from the 9th to the 18th of the following month, a total of 10 days. However, when ovulation is affected by mental stress, medications (such as short-acting contraceptives) and other factors, it may be advanced or pushed back, so ovulation should also be calculated under the guidance of a doctor. For women of gestational age who are preparing for pregnancy, they can calculate the ovulation period under the guidance of a doctor by using the calendar method, basal body temperature measurement and ultrasound to monitor follicular development, and have intercourse at this time to improve the chances of conception. For those who have been actively preparing for pregnancy but have not conceived for one year, they need to go to the hospital in time to find out the cause and actively treat it.