There are many ways to determine ovulation, here are some common ones:

2. Observe symptoms: During ovulation, women may feel some symptoms, such as breast swelling, headache, and changes in appetite. These symptoms usually occur when hormone levels rise in a woman's body.

3. Use a calendar: Using a calendar can help determine when a woman is ovulating. Women can usually ovulate around the 14th of each month.

4. Measure your urine: Women can determine if they are ovulating by measuring their urine. Often, some signs of elevated hormone levels will be detected in the urine, such as a positive urine HCG test result.

5. Use B-ultrasound: It is a common method to use B-ultrasound to determine a woman’s ovulation period. B-ultrasound can observe a woman's uterus and ovaries and determine when she is ovulating.

The above are some common ways to determine ovulation. However, these methods cannot completely accurately determine a woman's ovulation period, because a woman's menstrual cycle is affected by many factors, such as mood, health, etc. Therefore, women are advised to seek advice from their doctor or professional nutritionist to determine the best calculation method.