Inability to sleep during ovulation may be caused by a variety of factors. During ovulation, a woman's egg is released from the ovary and enters the fallopian tube to wait for fertilization. During this process, women's bodies undergo a series of changes that may cause them to feel uncomfortable, including insomnia.

1. Changes in hormone levels in the body: During ovulation, hormone levels in a woman’s body will change, including adrenaline and cortisol. Changes in these hormone levels may lead to insomnia.

2. Psychological stress: During ovulation, women may face a lot of psychological stress, such as worrying about whether they are pregnant or worrying about the uncertainty of the future. These psychological stresses may also lead to insomnia.

3. Physical discomfort: Physical discomfort may occur during ovulation, such as diarrhea, nausea, headache, etc. These physical complaints may lead to insomnia.

4. Environmental factors: Environmental factors may also affect women’s sleep, such as noise, light, etc. During ovulation, women may feel more sensitive and therefore more susceptible to environmental factors.

If women always have trouble falling asleep during ovulation, it is recommended that they try the following methods to improve their sleep:

1. Maintain a regular sleep time: Maintaining a regular sleep time can help women better adjust their biological clock, making it easier to fall asleep.

2. Avoid stimulating drinks such as coffee, tea and alcohol: These drinks may make it difficult for women to fall asleep, so women are advised to avoid drinking these drinks.

3. Relax the body and mind: Women can improve their sleep by relaxing the body and mind, such as meditation, deep breathing, etc.

4. Improve the sleeping environment: Women can improve their sleep by improving the sleeping environment, such as adjusting the temperature of the room, reducing noise, etc.

5. Seek help from a doctor: If women always have trouble falling asleep during ovulation, it is recommended that they seek help from a doctor to find more effective ways to improve sleep.