If the usual menstrual period is regular, if the 6th comes to menstruation ovulation is 18-25, a total of 8 days of time. If you are planning to get pregnant, you should arrange your sex life within these 8 days so as to increase the chances of getting pregnant. It is recommended that you should have intercourse 3 times during this period, and each time you have intercourse, you should space it out. If you don’t want to plan a pregnancy, you must take good contraceptive measures when you are ovulating, so as not to cause pregnancy and need to terminate the pregnancy, which will bring great harm to women. Calculating the ovulation period can be relatively accurate only if the menstrual cycle is regular, and it is difficult to calculate the ovulation period if the menstrual cycle is irregular.