Is the female safe period calculator accurate?

Patient's question:

No

Doctor's answer:

The calculation of the female safe period calculator is based on the date when menstruation is clean to the day before the start of ovulation, which is the pre-ovulation safe period. From the day after ovulation ends to the day before the next menstrual period arrives is the post-ovulation safe period. Generally speaking, the post-ovulation safe period is safer than the pre-ovulation safe period. This is because some women may experience ovulation earlier due to environmental changes and emotional fluctuations, which shortens the pre-ovulation safe period without their knowledge, making it less safe. The chance of an ovary releasing two eggs in one menstrual cycle is extremely rare. The safe period, which is from ovulation to the next menstrual period, usually does not involve a second ovulation, so the post-ovulation safe period is relatively safer.