How to Know How to Know Ovulation and Safe Periods is a Chinese article with a title of about 900 words at the beginning:

If you're considering pregnancy or trying to have a baby, understanding ovulation and safe periods is essential. These periods are dangerous because pregnancy can cause serious health problems, so it's important to know about them.

Generally speaking, a woman's menstrual cycle is about 28 days, but some people have fluctuations, so it is difficult to accurately predict when ovulation and safe periods will be. However, here are some ways to help you learn about them:

1. Watch for symptoms: Some women may experience symptoms during ovulation, such as increased body temperature, breast swelling, nausea, headache, and fatigue. If you notice these symptoms, you may want to wait until they are over before planning a pregnancy.

2. Measure body temperature: A woman’s basal body temperature can reflect when they are ovulating. The measurement method is to measure the body temperature when waking up every day and then record the changes in body temperature. Generally speaking, during ovulation, the body temperature will rise by about 0.3-0.5 degrees Celsius.

3. Observe menstruation: If a woman’s menstrual cycle is about 28 days, then the 14th day of their menstrual cycle is usually their ovulation period. During this period, a woman's body temperature will rise and she may experience some symptoms. However, this method is not always accurate, as some women may experience early or late menstruation.

4. Use a pregnancy test stick: A pregnancy test stick can help women detect whether they are pregnant during the ovulation period. Generally speaking, during the ovulation period, pregnancy tests will detect the presence of HCG (human chorionic gonadotropin).

5. Doctor's advice: If a woman wants to get pregnant, it is best to consult her doctor. Doctors can help women determine when is the best time to get pregnant based on their menstrual cycle and symptoms.

The above are some methods that can help women understand how to plan for pregnancy during ovulation and safe periods. However, these methods are not always accurate, so it is best for women to consult their doctor to determine the best time to get pregnant.