The main hazards of irregular menstruation are anemia, gynecological diseases and infertility. 1. Anemia: if there is menstrual irregularity with excessive menstruation, it is easy to become anemic if left untreated for a long period of time. Anemia that is not dealt with in time can harm all the organs of the body and cause serious effects. 2. Gynecological diseases: in the case of irregular menstruation with scanty menstrual flow, the general cause of the disease is medication or medical injury, and there may be gynecological diseases such as uterine adhesions and endometritis, which lead to a series of symptoms. 3. Infertility: Irregular menstruation may be caused by hyperprolactinemia, polycystic ovary and other diseases, without timely treatment will be early amenorrhea, resulting in infertility or post-pregnancy habitual abortion, affecting fertility. Irregular menstruation has a great impact on the body, women who find themselves with symptoms of irregular menstruation such as excessive menstruation, low menstruation, late menstruation and so on, need to pay attention to it and go to the regular hospital for examination in a timely manner.