How can you know the day of ovulation

Patient's question:

No

Doctor's answer:

The ovulation period is calculated starting from the first day of the next menstrual period. Counting backwards 14 days or subtracting 14 days gives the ovulation day. The ovulation day, along with the 5 days before it and the 4 days after it, together constitute the ovulation period. If the menstrual cycle is irregular, the calculation formula for the ovulation period is: First day of ovulation period = Shortest menstrual cycle days - 18 days; Last day of ovulation period = Longest menstrual cycle days - 11 days.