It is considered to be caused by delayed menstruation, such as lifestyle habits, emotional factors, pregnancy, cold stimulation during menstruation, malnutrition, side effects of drugs, endocrine dysfunction, gynecological diseases, etc. If you have sexual intercourse you should take a pregnancy test in time to observe whether there is a possibility of pregnancy. First of all, you should adjust your mind, maintain good habits, live a regular life, and eat more food containing nourishing or iron-rich food to avoid iron deficiency anemia. Secondly, you can use Chinese herbal medicine to regulate menstruation and nourish the liver and kidneys, such as Ju Yuan Decoction combined with Guei Kidney Pill plus or minus, Prosperity San plus or warm menstruation soup plus or minus, etc. At the same time, you should pay attention to prevent cold and keep warm, as cold during menstruation can easily lead to vasoconstriction in the pelvic cavity, resulting in ovarian dysfunction.