A clean period usually enters ovulation in about 7 days, and ovulation occurs on about the 14th day before the next period.
For a person with a 28-day menstrual cycle, ovulation occurs on the 14th day of the menstrual cycle, and if the period lasts for 7 days, then ovulation enters in about 7 days.
With a normal menstrual cycle, the 14th day before the next menstrual period is the day of ovulation, and within five days before and five days after the day of ovulation are considered the ovulation period, also called the danger period.
If you have a long menstrual cycle, the safe period after the menstrual period is longer, and if you have a short menstrual cycle, the safe period after the menstrual period is shorter, and there is no so-called safe period.
If you want to prepare for pregnancy, it is best to monitor the follicles by color ultrasound, when the follicles grow to about 18 to 23 millimeters, to ensure that it is easier to get pregnant by having sex every other day.