Peri-ovulatory bleeding is not serious if menstruation occurs about ten days apart. However, if the bleeding is caused by uterine fibroids, endometrial polyps, endometrial cancer, etc., it is not serious in mild cases, but more serious in severe cases. Determining whether having periods about ten days apart is serious or not depends on the actual situation and cannot be generalized. Usually, ten days after the end of menstruation is considered to be the period of ovulation, so if the bleeding is peri-ovulatory and the bleeding is small, it is usually not serious. It normally stops on its own and only lasts for one to three days. However, if menstruation comes back about ten days apart is irregular vaginal bleeding caused by diseases such as uterine fibroids, endometrial polyps, endometrial cancer, etc., if the treatment is timely and the condition is mild, it is not serious; if the diagnosis is not made in time, the heavier condition is more serious, and it may affect the ability to have children or jeopardize the life. To summarize, if menstruation occurs about 10 days apart, it is normal, and the patient needs to go to the hospital in time to clarify the specific cause and cooperate with the doctor for treatment.