A few days before menstruation is the ovulation period

The method of calculating ovulation a few days before menstruation is usually by measuring basal body temperature. Basal body temperature refers to a person's body temperature measured in a quiet state. It usually takes 12-24 hours to return to normal levels. At the beginning of the cycle, the body temperature will be relatively low, and then gradually increase until it reaches a peak mid-cycle (usually around day 14), and then begins to decrease.

According to some studies, the likelihood of ovulation in the days before your period is about 75%. However, this is only an estimate and accuracy may vary from person to person. Additionally, each person's cycle may differ due to individual differences and physiological factors.

If you want to determine whether you are ovulating a few days before menstruation, you can observe your body temperature changes and record the changes in body temperature during the cycle. In addition, you can also observe your symptoms in your daily life, such as breast swelling and changes in appetite.