This is an accurate calculation of ovulation for women: if the menstrual cycle is normal, for example, if the cycle is once every 30 days, if the period comes on the 1st, the ovulation day will be on the 16th, 4 days before and 3 days after the 16th, a total of 8 days, which is the ovulation period. However, the prerequisite for calculating ovulation is that the menstrual cycle is regular. If it is not regular, the calculated ovulation period is not accurate. Therefore, the menstrual cycle must be regular in order to accurately calculate a woman’s ovulation. If you want to plan a pregnancy, you can have intercourse during the ovulation period, but you must space it out to increase your chances of getting pregnant.