I am often asked by patients in the clinic how to calculate ovulation, so today I will take the time to explain in detail: each menstrual cycle is divided into follicular phase and luteal phase, the dividing line between the two is ovulation, follicular phase refers to the first day of menstruation until ovulation, this period is not fixed; luteal phase refers to the period after ovulation until the onset of menstruation, this period is roughly the same, 14 days. In other words, 14 days before the next menstrual period is the day of ovulation in this menstrual cycle. If you are planning to conceive, you can consider having intercourse two days before, on and two days after the day of ovulation to increase the probability of conception.