The normal cycle of menstruation is about 28 days, which is easily affected by emotion, diet and environment, etc. If it is advanced or pushed back by 7 days, it is generally within the acceptable range, and occasionally there are 1-2 time abnormalities, such as postponement by 4 days, there is no need to worry too much and no need for special treatment, but for women who are preparing for pregnancy, they need to clarify whether pregnancy. If a woman has concerns due to delayed menstruation, or subsequent delayed menstruation for more than 7 days, or every delayed menstruation, she can consider going to the hospital for examination: 1. Ultrasound examination: The thickness of the endometrium will change with the menstrual cycle, and generally the thickness of the endometrium can be observed through ultrasound examination, and the presence or absence of menstruation in the near future can be inferred. If the endometrial thickness is found to be sufficient, such as around 1.1cm, it generally means that menstruation can be expected in the short term, so be patient and keep observing; however, if the endometrial thickness is thin, such as below 0.8cm, combined with irregular menstruation, it may mean that there will be no menstruation recently, and progesterone and progesterone need to be taken to improve the situation and try to restore the normal menstrual cycle; 2. Sex hormone six test and other endocrine system tests: to clarify whether there is abnormal hormone secretion and to provide targeted treatment for the cause; 3. Blood test for HCG: if a woman is in her reproductive age, has a normal sexual life and does not take contraceptive measures, the possibility of pregnancy should be considered and a blood test for HCG can be drawn to make a diagnosis.