Tummy pain when ovulation occurs is due to a small amount of follicular fluid when the follicle ruptures. With the rupture of the follicle, there may be a rupture of the blood vessels on the surface of the ovary as well, and there will be a small amount of bleeding to stimulate the peritoneum, causing pain in the lower abdomen; some people have more obvious symptoms and this occurs every 1 month. If the pain is mild, it usually disappears in 1 day and can be observed for the time being. If the pain is more severe and there is more intra-abdominal bleeding, hospitalization is required for observation, application of hemostatic drugs, and avoiding activities and ultrasound examination at any time. If there is more pelvic fluid and the patient’s symptoms are more severe, surgery is needed. If this phenomenon occurs every time, patients who cannot tolerate it can apply short-acting oral contraceptives to inhibit ovulation and apply them for 3 months before menstruation, and the symptoms may improve.